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China Star Optics Technology Co., Ltd. is one of China`s leading optical manufacturing companies, which was registered and established in Changchun,Jilin province in 2005. Our company has been engaged in manufacturing of optical components for nearly 20 years, we have wide experience and advantages in processing high precision optical components, such as optical lenses, aspherical lens, optical dome, optical windows, optical coatings and infrared optical parts etc. The components are widely used in medical instrument,optical communications, photography, biochemical analysis,laser systems, aerospace and other fields. We have strict quality control in the production of optical components, to improve our inspection capabilities, we have been equipped with advanced inspection equipments, including ZYGO Verifire Interferometer, Goniometer,Autocollimator, Theodolite and Spectrophotometer etc. Ensures that we can provide high quality prodcuts and efficiency service. We look forward to hearing from you with developing a long-term friendly business relationship in near future.

The optical properties of quartz glass are unique. It can pass through the far-ultraviolet spectrum, and is the best for all UV-transparent materials, as well as visible and near-infrared. The user can arbitrarily select the desired variety from the range of 185-3500 mμ band as needed. Due to its high temperature resistance, quartz glass has a very small thermal expansion coefficient and good chemical thermal stability. Bubbles, stripes, uniformity and birefringence are comparable to those of ordinary optical glass, so it is a highly stable optical system that works in a variety of harsh environments. Essential optical material. The structure of quartz glass, impurity content, OH gene, NO, CO and other content are the main factors affecting the spectral transmittance. The oxygen atom binding failure has an absorption peak at 0.24μ, and quartz glass containing OH group at 2.7μ. Due to the molecular vibration, a significant absorption peak will be produced, and the low ultraviolet transmittance is mainly caused by the atomic absorption spectrum caused by the metal impurities. Spectral characteristic curve of quartz glass Fused silica glass is a very good infrared transparent material, but the ultraviolet transmittance is low due to the presence of impurities. The quartz glass obtained by melting the crystal of the oxyhydrogen flame has an absorption peak at 0.24 μ and an OH group due to the oxygen structure defect, so the infrared transmission is extremely low. High-purity optical quartz glass smelted with synthetic raw materials is the best UV-permeable material, but has a severe OH absorption peak at 2.7 μ. Only the optical quartz glass which is formed by melting the synthetic raw material by electrofusion or hydrogen-free flame can well penetrate the continuous spectrum from far ultraviolet to near infrared.

British astronomer Herschel discovered infrared technology in 1800. In the constant efforts of the scientific community, infrared technology has also been applied to various occasions. The most typical one for security applications is the infrared camera. Infrared cameras can be divided into 2 categories, analog infrared cameras and infrared network cameras. But they all have the same characteristics, which are mainly manifested in the different characteristics of infrared light source and the choice of low illumination camera. Only by combining these two points with an infrared camera can you become an excellent product. In selecting different infrared light sources and distances, the main infrared light source characteristics for different applications are as follows: Infrared light is an invisible light with a wavelength greater than 780 nm. Generally, the infrared lamps of current infrared cameras have the following types. 1. Use infrared light emitting diode LEDs or LED arrays to generate infrared light. Such devices generate infrared light by recombining electrons and holes in a gallium arsenide (GaAs) semiconductor. 2. The infrared laser diode LD can also be used as an infrared light source. However, it is necessary to excite or pump electrons in a lower energy state to a higher energy state, and maintain the stimulated radiation infrared light by reversing a large amount of particle distribution and resonating. The first is an infrared lamp composed of a semiconductor gallium arsenide LED array, especially an array-type integrated light-emitting chip LEDArray that is now developed using a new technology. Its LED-Array has an optical output of 800mw-1000mw, which has become a replacement for ordinary LEDs. The LED-Array has a half-power angle of 10-120° (variable angle). Since the LED-Array is a highly integrated LED and the size is only one penny coin, its life span is 50,000 hours. The second is to use an infrared laser diode LD. For the monitoring of ultra-long-distance scenes of more than 1km, it is still necessary to select an infrared LD source. Because semiconductor lasers have higher brightness and better directivity than LEDs. Infrared camera installation and debugging need to pay attention to the following issues: First of all, debugging infrared lights must be done at night. The infrared beam illumination position is adjusted at night by a rendering device such as a monitor. And can effectively adjust the lens aperture settings. Secondly, the infrared light can't directly face the camera. The infrared light seen by the camera is like the sunlight seen by humans, which will make the image appear white. Again, the infrared light is not necessarily mounted in the same position as the camera. If the camera is far away from the object being illuminated, consider installing the infrared light between the two. The best way to install in the same position is to overlap the camera with the infrared light and the camera. Finally, users should first read the instruction manual carefully when using the infrared light, especially the precautions for ensuring the safety of personal equipment. Check whether the matching aspects described above meet the requirements, and whether the influencing factors should be taken into consideration, if the requirements are not met, the equipment used can be adjusted in time. The use of large-angle infrared light with a small angle of view lens, there is a waste of light. Secondly, the larger the emission angle of the infrared light, the better the picture effect. The relative aperture determines the light-passing ability of the lens. The relative light-through of the lens with a relative aperture of f1.0 is four times that of the lens with a relative aperture of f2.0. The same camera and infrared light are matched with the above two lenses, and the infrared distance is It can be doubled. The large-aperture lens is four to ten times better than the conventional lens in infrared monitoring. It is reasonable to say that it should be an essential accessory for infrared night vision monitoring. However, due to the high cost and technical difficulty, most infrared products Manufacturers do not have the ability to supply. The problem of focus shift: visible light and infrared light are different in wavelength, the imaging focus is not on a plane, resulting in clear image under visible light conditions in the daytime, blurred under nighttime infrared light conditions, or clear image under nighttime infrared light conditions, daytime visible light conditions The image below is blurred. All black and white cameras are infrared light. Infrared light is a kind of stray light for color cameras under visible light conditions, which will reduce the sharpness and color reproduction of color cameras. The color camera filters prevent infrared rays from participating in imaging. There are two ways to make the color camera sense infrared. First, switch the filter to block the infrared light from entering under visible light conditions; remove the filter in the absence of visible light and let the infrared light enter. The image quality is good, but the cost is high and the switching mechanism will cause a certain failure rate. Second, open a specific infrared channel on the filter, allowing infrared light of the same wavelength as the infrared light to come in. This method does not increase. Cost, but the color reproduction is slightly worse. At present, infrared night vision distance has been more than 500 meters, and price is also one of the reasons. Among them, infrared light, infrared camera technology, infrared lens is the core.

Many of my friends are wondering why the same focal length lens will be divided into ordinary lenses and infrared lenses. What is the difference between ordinary lenses and infrared lenses? Next we will briefly explain the difference between the two: First of all, the use of the two is different: In the surveillance environment that does not require infrared light subsidies, an ordinary lens can be used. In an infrared light-subsiding surveillance environment, an infrared lens must be used for better monitoring effects; Can see the picture, but the picture will become blurred, this point I believe everyone has a deep understanding. Second, the prices of the two are different: The price of a professional infrared lens is several times that of an ordinary lens. Why? Because the use of an infrared lens is both clear during the day and at night, and the effect is natural and expensive. Oh, this is nonsense. Finally, I talk about the reasons why the performance and price of the two are so different: Because the refractive index of the glass for different wavelengths of light is different, the position of the focused point will be different. Currently on the market, ordinary lenses can achieve the wavelength difference of about 250nm on the same plane, that is, 430 ~ 650nm or 650 ~ The light in the 900 nm range can be successfully focused and present a clear image. This is why the ordinary lens is clear during the day, the night vision is blurred, or the night vision is clear and the daytime is blurred. Professional-infrared lens uses special lenses, can achieve the 430 ~ 900nm or even longer wavelength range of the light gathered on the same plane, so regardless of the day or night vision is clear. Due to the special lens material, so the cost Naturally high. Professional infrared lens cost is high, new problems come again, everyone has to do a high cost of the machine, the profit is low, how to do? The people are very smart, do point coating to the lens, amend the light, hey, Cheap infrared lens comes out slightly ~ and no matter how good or bad, all are called - infrared lens! But how is the effect? How long will the coating be removed?... Will it be evaporated after being heated?... The plating is not as uniform as it should be, but sometimes it will be a little blurry. How can I do it? The goods requirement is not too high.. In any case, the best is cheap! We all recommend that everyone use good equipment, after all, a penny and a piece of goods, you buy it and use it comfortably, and we sell it comfortably. Although we just added more costs, our profits are the same, but if the equipment Praised by the majority of customers, the effect is different response. Finally, I wish you all a happy and prosperous business.

Many of my friends are wondering why the same focal length lens will be divided into ordinary lenses and infrared lenses. What is the difference between ordinary lenses and infrared lenses? Next we will briefly explain the difference between the two: First of all, the use of the two is different: In the surveillance environment that does not require infrared light subsidies, an ordinary lens can be used. In an infrared light-subsiding surveillance environment, an infrared lens must be used for better monitoring effects; Can see the picture, but the picture will become blurred, this point I believe everyone has a deep understanding. Second, the prices of the two are different: The price of a professional infrared lens is several times that of an ordinary lens. Why? Because the use of an infrared lens is both clear during the day and at night, and the effect is natural and expensive. Oh, this is nonsense. Finally, I talk about the reasons why the performance and price of the two are so different: Because the refractive index of the glass for different wavelengths of light is different, the position of the focused point will be different. Currently on the market, ordinary lenses can achieve the wavelength difference of about 250nm on the same plane, that is, 430 ~ 650nm or 650 ~ The light in the 900 nm range can be successfully focused and present a clear image. This is why the ordinary lens is clear during the day, the night vision is blurred, or the night vision is clear and the daytime is blurred. Professional-infrared lens uses special lenses, can achieve the 430 ~ 900nm or even longer wavelength range of the light gathered on the same plane, so regardless of the day or night vision is clear. Due to the special lens material, so the cost Naturally high. Professional infrared lens cost is high, new problems come again, everyone has to do a high cost of the machine, the profit is low, how to do? The people are very smart, do point coating to the lens, amend the light, hey, Cheap infrared lens comes out slightly ~ and no matter how good or bad, all are called - infrared lens! But how is the effect? How long will the coating be removed?... Will it be evaporated after being heated?... The plating is not as uniform as it should be, but sometimes it will be a little blurry. How can I do it? The goods requirement is not too high.. In any case, the best is cheap! We all recommend that everyone use good equipment, after all, a penny and a piece of goods, you buy it and use it comfortably, and we sell it comfortably. Although we just added more costs, our profits are the same, but if the equipment Praised by the majority of customers, the effect is different response. Finally, I wish you all a happy and prosperous business.

Many of my friends are wondering why the same focal length lens will be divided into ordinary lenses and infrared lenses. What is the difference between ordinary lenses and infrared lenses? Next we will briefly explain the difference between the two: First of all, the use of the two is different: In the surveillance environment that does not require infrared light subsidies, an ordinary lens can be used. In an infrared light-subsiding surveillance environment, an infrared lens must be used for better monitoring effects; Can see the picture, but the picture will become blurred, this point I believe everyone has a deep understanding. Second, the prices of the two are different: The price of a professional infrared lens is several times that of an ordinary lens. Why? Because the use of an infrared lens is both clear during the day and at night, and the effect is natural and expensive. Oh, this is nonsense. Finally, I talk about the reasons why the performance and price of the two are so different: Because the refractive index of the glass for different wavelengths of light is different, the position of the focused point will be different. Currently on the market, ordinary lenses can achieve the wavelength difference of about 250nm on the same plane, that is, 430 ~ 650nm or 650 ~ The light in the 900 nm range can be successfully focused and present a clear image. This is why the ordinary lens is clear during the day, the night vision is blurred, or the night vision is clear and the daytime is blurred. Professional-infrared lens uses special lenses, can achieve the 430 ~ 900nm or even longer wavelength range of the light gathered on the same plane, so regardless of the day or night vision is clear. Due to the special lens material, so the cost Naturally high. Professional infrared lens cost is high, new problems come again, everyone has to do a high cost of the machine, the profit is low, how to do? The people are very smart, do point coating to the lens, amend the light, hey, Cheap infrared lens comes out slightly ~ and no matter how good or bad, all are called - infrared lens! But how is the effect? How long will the coating be removed?... Will it be evaporated after being heated?... The plating is not as uniform as it should be, but sometimes it will be a little blurry. How can I do it? The goods requirement is not too high.. In any case, the best is cheap! We all recommend that everyone use good equipment, after all, a penny and a piece of goods, you buy it and use it comfortably, and we sell it comfortably. Although we just added more costs, our profits are the same, but if the equipment Praised by the majority of customers, the effect is different response. Finally, I wish you all a happy and prosperous business.

Modern communication systems often use dual band bandpass filters to isolate different operating bands in the same network. The traditional design dimensions of such filters are relatively large and require an additional combined network for the two filters. However, the dual-band bandpass filter design method discussed in detail in this paper can be made very small. Its structure is relatively simple, consisting of two asymmetric split spiral resonators (ASSR) cascaded with a microstrip line. Due to the inherent spiral geometry of the ASSR, the ASSR can be fully embedded in the microstrip line, so the final design size can be minimized. This paper also further analyzes this innovative design and validates this design approach with a pair of prototypes. The two dual band filters operate between 1.16 GHz and 1.84 GHz and between 1.80 GHz and 2.45 GHz, respectively. The industry has made a lot of efforts to miniaturize the dual-band bandpass filter. For example, a cross-coupled filter is a relatively efficient solution. In this design method, an isometric split-ring resonator with dual resonant frequency response characteristics is used as the basis for the design of the filter. In one example, a cross-coupled dual-band bandpass filter is synthesized using four resonators, and the relative positions of these resonators must be carefully tuned in order to obtain a suitable coupling coefficient. Unfortunately, the use of four resonators results in reduced insertion loss performance and the difficulty of achieving compact dimensions (especially cross-sectional dimensions). Another approach is to use an open-loop resonator and a parallel open stub as the basis for the design of a compact dual-band bandpass filter. Designed and manufactured here are three dual-band filters optimized for out-of-band rejection. In these prototypes, the second passband can be controlled by adjusting the position and length of a particular parallel open stub. There is also a micro-planar dual-band bandpass filter based on a curved stepped impedance resonator (SIR). The dual-band response of this filter depends on the main geometric parameters of the SIR, while the compact size is achieved by integrating the U-shaped SIR with the latest coupling mechanism. A miniature dual-band bandpass filter is also implemented using a combined coupling structure of short and open quarter-wavelength SIR. In summary, these different dual-band filter design methods rely on a basic unit with a dual resonant mode. This article provides different design methods for creating compact, dual-band bandpass filters. In this new approach, the filter consists of two cascaded ASSRs connected by microstrip lines. These ASSRs are an improved version of a single plane double helix resonator unit and a symmetric split type spiral resonator. Due to its special geometry, this ASSR can be fully embedded in the microstrip feed line to directly form the corresponding component with a compact cross-sectional dimension. In general, ASSR is a band-pass unit that operates by electromagnetic (EM) coupling. In the current design, the first passband is dependent on the inherent passband of the ASSR, while the second passband is created by a combination of an equal impedance network of ASSRs and connected microstrip lines. Thus, the second passband can be adjusted independently of the first passband by using the length of the connected microstrip line as a variable parameter. This conclusion will also be verified by circuit model analysis. Based on this analysis, we designed and fabricated two different dual-band bandpass filters to demonstrate the effectiveness of the analysis. According to our knowledge, these dual-band bandpass filters are the narrowest filters reported in all the literature to date due to their particularly compact cross-sectional dimensions. Figure 1: The layout shows ASSR(a) and the recommended dual-band bandpass filter (b). This filter uses a pair of ASSRs and a microstrip transmission line connected to it. Figure 1 shows the ASSR layout (a) and recommended filter (b) used in this dual-band bandpass filter. Each ASSR consists of two separate, asymmetrical rectangular spiral patterns. Due to the rotational geometry of the rectangular helix, a given unit can be fully embedded within the microstrip line, resulting in a particularly compact cross-sectional dimension. Thus, the ASSR Broadband W1 remains unchanged at 4.6 mm, which is equivalent to the width of a 50Ω microstrip line fabricated on Rogers' RT/duroid 5880 printed circuit board (PCB) substrate. The relative dielectric constant of this substrate is 2.2. The thickness is 1.5mm. These material values are also used for simulation. The values for dimensions W3 and W4 are limited due to limitations imposed by circuit manufacturing tolerances (approximately 0.1 mm at W1 = 4.6 mm). For these dual band bandpass filter designs, the values for W3 = 0.6 mm and W4 = 0.3 mm are used here. In a common model of a coupled microstrip line filter, these values will support the effective bandpass properties through electromagnetic coupling. This prediction will be verified by the parameter analysis method of L1 (the main adjustment parameter of the bandpass filter), and the result is shown in Fig. 2.

Modern communication systems often use dual band bandpass filters to isolate different operating bands in the same network. The traditional design dimensions of such filters are relatively large and require an additional combined network for the two filters. However, the dual-band bandpass filter design method discussed in detail in this paper can be made very small. Its structure is relatively simple, consisting of two asymmetric split spiral resonators (ASSR) cascaded with a microstrip line. Due to the inherent spiral geometry of the ASSR, the ASSR can be fully embedded in the microstrip line, so the final design size can be minimized. This paper also further analyzes this innovative design and validates this design approach with a pair of prototypes. The two dual band filters operate between 1.16 GHz and 1.84 GHz and between 1.80 GHz and 2.45 GHz, respectively. The industry has made a lot of efforts to miniaturize the dual-band bandpass filter. For example, a cross-coupled filter is a relatively efficient solution. In this design method, an isometric split-ring resonator with dual resonant frequency response characteristics is used as the basis for the design of the filter. In one example, a cross-coupled dual-band bandpass filter is synthesized using four resonators, and the relative positions of these resonators must be carefully tuned in order to obtain a suitable coupling coefficient. Unfortunately, the use of four resonators results in reduced insertion loss performance and the difficulty of achieving compact dimensions (especially cross-sectional dimensions). Another approach is to use an open-loop resonator and a parallel open stub as the basis for the design of a compact dual-band bandpass filter. Designed and manufactured here are three dual-band filters optimized for out-of-band rejection. In these prototypes, the second passband can be controlled by adjusting the position and length of a particular parallel open stub. There is also a micro-planar dual-band bandpass filter based on a curved stepped impedance resonator (SIR). The dual-band response of this filter depends on the main geometric parameters of the SIR, while the compact size is achieved by integrating the U-shaped SIR with the latest coupling mechanism. A miniature dual-band bandpass filter is also implemented using a combined coupling structure of short and open quarter-wavelength SIR. In summary, these different dual-band filter design methods rely on a basic unit with a dual resonant mode. This article provides different design methods for creating compact, dual-band bandpass filters. In this new approach, the filter consists of two cascaded ASSRs connected by microstrip lines. These ASSRs are an improved version of a single plane double helix resonator unit and a symmetric split type spiral resonator. Due to its special geometry, this ASSR can be fully embedded in the microstrip feed line to directly form the corresponding component with a compact cross-sectional dimension. In general, ASSR is a band-pass unit that operates by electromagnetic (EM) coupling. In the current design, the first passband is dependent on the inherent passband of the ASSR, while the second passband is created by a combination of an equal impedance network of ASSRs and connected microstrip lines. Thus, the second passband can be adjusted independently of the first passband by using the length of the connected microstrip line as a variable parameter. This conclusion will also be verified by circuit model analysis. Based on this analysis, we designed and fabricated two different dual-band bandpass filters to demonstrate the effectiveness of the analysis. According to our knowledge, these dual-band bandpass filters are the narrowest filters reported in all the literature to date due to their particularly compact cross-sectional dimensions. Figure 1: The layout shows ASSR(a) and the recommended dual-band bandpass filter (b). This filter uses a pair of ASSRs and a microstrip transmission line connected to it. Figure 1 shows the ASSR layout (a) and recommended filter (b) used in this dual-band bandpass filter. Each ASSR consists of two separate, asymmetrical rectangular spiral patterns. Due to the rotational geometry of the rectangular helix, a given unit can be fully embedded within the microstrip line, resulting in a particularly compact cross-sectional dimension. Thus, the ASSR Broadband W1 remains unchanged at 4.6 mm, which is equivalent to the width of a 50Ω microstrip line fabricated on Rogers' RT/duroid 5880 printed circuit board (PCB) substrate. The relative dielectric constant of this substrate is 2.2. The thickness is 1.5mm. These material values are also used for simulation. The values for dimensions W3 and W4 are limited due to limitations imposed by circuit manufacturing tolerances (approximately 0.1 mm at W1 = 4.6 mm). For these dual band bandpass filter designs, the values for W3 = 0.6 mm and W4 = 0.3 mm are used here. In a common model of a coupled microstrip line filter, these values will support the effective bandpass properties through electromagnetic coupling. This prediction will be verified by the parameter analysis method of L1 (the main adjustment parameter of the bandpass filter), and the result is shown in Fig. 2.

The optical component is a very precise component, and the manufacturing cost is high. If the thickness of the component can be reduced, or even a sheet lens, the size of the optical component can be reduced, thereby reducing the size of the lamp or other equipment, and saving material. cut costs. As the thickness is reduced, the light absorption is also reduced, and the efficiency of the luminaire or instrument is also increased. Therefore, it is one of the goals of optical design to make high-quality sheet-shaped optical parts. The Fresnel lens is a sheet-like thin lens that has been used in some aspects for its lightness, thinness and low cost. However, the Fresnel lens on the market is mostly concentric circle structure with equal radius. The fabrication lacks precise optical design process, resulting in low image quality, and some even simple corrugated structures, and its optical quality is even worse. . Even a better Fresnel lens is usually formed by dividing a common lens into small segments, which are approximately broken lines, and are formed by simple translation of different distances. The defects in these design methods result in low quality of the Fresnel lens. LEDs are small in size, but most of the LED lenses on the market are thicker than 10mm, which is a fatal problem for LEDs in some applications, although Fresnel lenses can be used to reduce the thickness of the lens and reduce light absorption. However, how to carry out accurate optical design is rarely reported in the literature. This article describes the design method for obtaining accurate ultra-thin zigzag lenses with good optical quality and high light utilization. Because the general Fresnel lens is theoretically wasteful, that is, the light passing through the lens theoretically has a part that cannot reach the destination of the design, and the lens obtained by the method has no theoretical waste. In addition, the distance between the small serrations can also be different according to needs, and the zigzag spacing at different positions in the same lens can also be changed, so that the zigzag lens designed by this method has wider adaptability, that is, it can Adapt to different conditions of use and different processing conditions. This zigzag lens is suitable for secondary optical lenses in which the LED is a light source. For a small-sized light source such as an LED, it is very meaningful to have a small and thin optical lens. First, the design principle A single lens is generally a transparent material whose surface shape is curved, and its function is to change the direction of the light to form a desired spatial distribution of light intensity. The disadvantage is that it tends to be relatively thick, so it is bulky and costly, and the absorption is large, especially for lenses with large curvature. For the sake of simplicity, an example of a plano-convex lens is shown in Fig. 1(a). Correspondingly, the conventional Fresnel lens is shown in Fig. 1(b). For the sake of explanation, the pitch of the figure is relatively large. Figure 1 The formation principle of the traditional Fresnel lens The design principle of Fresnel lens is to replace the entire continuous large surface with several small faces. Figure 1 (c) shows the design principle of a conventional Fresnel lens. The function of the sawtooth Fresnel lens of Fig. 1(b) is the same as that of the original lens of Fig. 1(a). The traditional design method can be represented by Figure 1 (c). Actually, the Fresnel lens of Fig. 1(b) can be regarded as that a plurality of rectangular portions are deleted from the lens of Fig. 1(a), and the remaining portion is moved downward into a sheet shape to become a Fresnel lens. See Figure 1(c), where the stepped shadow is the part of the multiple rectangles that are deleted. It is obvious that the Fresnel lens of Fig. 1(b) is thinner than the lens (a), so that the absorption is small and the material is saved. However, this conventionally designed lens is correct only for parallel light, in which case the shaded portion of (c) has no effect on the light. However, in the case of non-parallel light, such as when the LED is a light source, the shaded portion of (c) has an effect on the light. If it is removed into a Fresnel lens, it will cause a lot of stray light. In addition, if the cross section of the lens is replaced by a broken line instead of a small arc, an optical error will also occur. In order to overcome the above shortcomings, we propose to design Fresnel lenses in two new ways. Here we design for a single LED. For other light sources, the design principle is the same, so in principle it can be extended to other light sources. The basic idea of the new method is to divide the edge of the deleted invalid part along the light, and the effective remaining part moves along the light while changing its size in a certain proportion, so that the light will not propagate in the lens. Hit the invalid part of the edge and it will be refracted in the original direction. This reduces the scattered light and increases the optical efficiency of the lens. Second, the design method 1, the angle method Figure 2 angle method We assume that the incident surface of the original lens is a plane, and the exit surface (the surface on which AB is located in Figure 2) is a curved surface. As for how to design the original surface, it is beyond the scope of this article. The new exit surface is the zigzag we want to design. In this paper, we can assume that the O point is the position of the virtual image point after the light source passes through the incident surface, that is, the light from the O point passes through the exit surface and reaches the image surface (the lens may not be "imaged" but illuminated). So we will include the role of the entrance surface. We can divide the surface where AB is located into small segments at the angle of the point O. In the figure, AB is one of the small segments. Instead of moving these small segments vertically as in the first section, we moved them in the direction of the light and scaled them while scaling. Thus, AB is scaled to A'B'. According to the principle of linear optics, the direction of light refraction caused by facet A'B' is exactly the same as that of facet AB, except that the position of the light is slightly different. Since the lens size is much smaller than the image distance, and the distance difference between OA and OA' is a second-order small amount, we can only care about the angle of the outgoing light before and after the design without concern for the position of the light. Minor changes, that is to say the facets before and after the change, will not make a significant difference in the optical effect of the entire lens, especially for illumination lenses. In addition, the division of the angles may be equal or unequal, and neither of these cases affects the optical effect. To illustrate the problem, Figure 2 only divides the lens into 8 parts. In fact, the larger the number of divisions, the thinner the lens can be. However, as mentioned below, a larger number will bring new problems. However, it can be seen that one disadvantage of the above method is that the sawtooth thickness of the lens will be different, which may affect the strength of the lens. Another method is proposed below, which can achieve the same thickness of the sawtooth. Although the design process is more complicated, it can not only overcome the problem of uneven thickness, but also eliminate stray light. 2, thickness method Figure 3 thickness method 3 is the same as the original lens of FIG. 2, but in FIG. 3, the original lens is divided into several parts in the thickness direction by equal distance (see the horizontal dotted line of FIG. 3), and then the same method is used in the upper section angle method. Each segment is linearly reduced while moving along the light to form a lens of substantially the same thickness. This method not only achieves the same sawtooth depth, but also increases the strength of the lens, and can reduce the thickness at the same number of teeth compared to the angle-angle method, or reduce the number of saw teeth at the same thickness. It can be seen from the analysis below that this result can also reduce stray light of the lens, thereby improving image quality and light utilization efficiency. It should also be pointed out that in general, as long as one of the two faces of the incident and outgoing faces is made into a serrated surface, the design requirements can be met. If the entrance surface is desired to be a sawtooth surface and the exit surface is flat, the above analysis is the same. For example, the outer surface can be a smooth surface and the inner surface can be a serrated surface, which prevents dust from accumulating. More importantly, if the side of the sawtooth is not a flat surface but a curved surface, the result is the same. In this way, we can not only make a flat-plate Fresnel lens, but also other Fresnel lenses such as curved tiles or bowls. Third, stray light analysis It can be seen from the analysis below that the sawtooth lens designed by the new method not only retains the advantages of the original method, but also reduces the stray light caused by the machining error. Because in the actual processing, the tip and bottom of the sawtooth can not be infinitely small, but have a certain rounded corner, this rounded corner will affect the light can not reach the place that should be reached, causing stray light. Figure 4 is a simulation result of a single sawtooth stray light. Figure 4 Simulation results of a single sawtooth stray light The amount of stray light is related to the accuracy of the processing. Assuming that the average width of the sawtooth is d, the radius of the corner of the sawtooth tip is r, and it is roughly assumed that the light in the r range becomes stray light, and the ratio of light loss is r/d. For example, the sawtooth width is 1 mm, and the machining accuracy is caused. Some r is 0.05mm, the light loss is 5%. This is the light loss that the Fresnel lens has to have, which is also a disadvantage of the Fresnel lens. However, compared to Fresnel lenses designed by other methods, the new method and other thickness methods can relatively reduce this loss. The reason for this is that the equal thickness method can have fewer sawtooth numbers under the same thickness conditions as compared with other methods, so that the average width d is larger, r/d is relatively smaller, and thus light loss is less. Further analysis knows that since the LED light source has a large luminous intensity in the optical axis portion and a small edge portion, the thickness obtained by the thickness method has a larger pitch in the middle portion than in the edge portion (see Fig. 3). There is less loss in places where the light intensity is high, that is, there can be less light loss overall. Figure 5 Example of two Fresnel lenses A three-dimensional lens can be obtained by rotating or stretching the designed section. Figure 5 is an example of two Fresnel lenses. The stretched (a) can be used for a strip spot, and the rotated (b) can be used for a circular spot. The design method uses a method of dividing the ideal optical surface and moving in the direction of the light while scaling, while maintaining the optical performance of the lens while minimizing the optical loss, and achieving higher efficiency than other methods. The method can obtain good effects on an LED light source with a small light source scale.

Microscope lenses are of different types, but even for the same type of lens, the imaging quality is very different, mainly due to factors such as material, processing accuracy and lens structure, and also leads to different grades of lens prices. A huge difference from a few hundred yuan to several tens of thousands. More famous such as four three-piece Tiansei lens, six four-group double Gauss lens. For the lens design and manufacturer, the optical transfer function OTF (Optical Transfer Function) is generally used to comprehensively evaluate the lens imaging quality. The optical system transmits the information along the spatial distribution of the brightness. The optical system is transmitted when transmitting the information of the subject. The sinusoidal signal of each spatial frequency, the degree of modulation and the change of phase in the actual image, are all functions of spatial frequency. This function is called the optical transfer function. The OTF is generally composed of a modulation transfer function MTF (Modulation Transfer Function) and a phase transfer function PTF (Phase Transfer Function). Aberration is an important aspect that affects image quality. Common aberrations are as follows: Ball difference: A monochromatic conical beam emitted from an object point on the main axis to the optical system is refracted by the optical series. If the original beam has different angles of light, it cannot be placed at the same position on the main axis, so that the ideal image on the main axis At the plane, a diffuse spot (commonly known as a blur circle) is formed, and the imaging error of the optical system is called a spherical aberration. Hypothesis: A monochromatic conical beam emitted from an off-axis object located outside the main axis to the optical system, after being refracted by the optical series, cannot form a clear point at the ideal image plane, but is formed by dragging a bright tail The illuminating star spot, the imaging error of this optical system is called coma. Astigmatism: An oblique monochromatic conical beam emitted from an off-axis object located outside the main axis to the optical system, after being refracted by the optical series, cannot form a clear image point, but can only form a diffuse spot. The imaging error of the optical system is called astigmatism. Field music: A clear image formed by a plane object perpendicular to the main axis through the optical system, if not in a plane perpendicular to the image plane of the main axis, and on a curved surface symmetrical on the main axis, that is, the best image plane is a curved surface, then The imaging error of the optical system is called field curvature. When the image is adjusted to the center of the screen, the image around the screen is blurred. When the image is blurred until the image around the screen is clear, the image at the center of the screen begins to blur. Color difference: A white object emits a white light to the optical system. After being refracted by the optical system, the light of each color cannot converge on one point, and a color image spot is formed, which is called chromatic aberration. The reason for the chromatic aberration is that the same optical glass has different refractive indices for light of different wavelengths, the short-wave light has a large refractive index, and the long-wave light has a small refractive index. distortion: The straight line outside the main axis in the object plane becomes a curve after being imaged by the optical system, and the imaging error of this optical system is called distortion. Distortion aberrations only affect the geometry of the image without affecting the sharpness of the image. This is the fundamental difference between distortion and spherical aberration, coma, astigmatism, and field music. When evaluating lens quality, we usually judge several practical parameters such as resolution, sharpness and depth of field. Resolution: Also known as discrimination rate, resolution, refers to the ability of the lens to clearly distinguish the details of the fiber of the scene, the reason for restricting the resolution of the lens is the diffraction phenomenon of light, that is, the diffraction spot (Eryer spot). The unit of resolution is line pair / mm. Acutance: Contrast, also known as contrast, refers to the contrast of the brightest and darkest parts of the image. Depth of Field (DOF): In the scene space, the scene located within a certain distance from the plane of the focus object can also form a relatively clear image. The depth distance between the above-mentioned scenes that can form a relatively clear image before and after the focus plane, that is, the depth range of the scene space that can obtain a relatively clear image on the actual image plane, is called the depth of field. Maximum relative aperture and aperture factor: Relative aperture refers to the ratio of the incident aperture diameter (indicated by D) to the focal length (indicated by f) of the lens, ie relative aperture = D / f. The reciprocal of the relative aperture is called the aperture scale, also known as the f/aperture coefficient or the aperture number. The relative aperture of a typical lens is adjustable, and its maximum relative aperture or aperture factor is often indicated on the lens, such as 1:1.2 or f/1.2. If the scene is dark or the exposure time is short, you need to choose the lens with the largest relative aperture. The interaction between the parameters of the lens A good lens has a good reflection in terms of resolution, sharpness, depth of field, etc. It is also better for correcting various aberrations, but at the same time its price will increase several times or even hundreds of times. If we have some rules and experience, we can use the same grade lens to achieve better results. 1. The effect of the focal length The smaller the focal length, the greater the depth of field; The smaller the focal length, the larger the distortion; The smaller the focal length, the more severe the vignetting phenomenon, and the illumination of the aberration edge is reduced; 2. Influence of aperture size The larger the aperture, the higher the brightness of the image; The larger the aperture, the smaller the depth of field; The larger the aperture, the higher the resolution; 3. Center and edge of the field Generally, the image center has higher resolution than the edge. Generally, the image center has higher illumination than the edge light field. 4. Effect of light length Under the same camera and lens parameters, the shorter the wavelength of the light source of the illumination source, the higher the resolution of the resulting image. Therefore, in a vision system that requires precise size and position measurement, short-wavelength monochromatic light is used as an illumination source as much as possible, which has a great effect on improving system accuracy.

[China Glass Net] The main advantages of laser glass compared to laser crystals are: (1) Easy to prepare. By applying the process technology for preparing optical glass and improving it, it is possible to obtain a highly transparent and optically uniform glass, which is relatively easy to produce a large-sized work substrate material, and has a low cost, and a large volume and a high density of activated particles are used for high power. And important advantages of high energy lasers. (2) The matrix glass is easy to change. The composition and properties of the matrix glass vary widely, and the types and amounts of activators added are not limited, so it is easy to develop into a series of laser glass varieties with various characteristics. (3) Easy molding processing. Using optical glass thermoforming and cold working processes, laser glass is easily molded into various shapes, such as rods, sheets, wires, etc., and is ground into high-precision optical surfaces to meet the needs of various device structure developments. (4) Based on the characteristics of the glass structure, that is, short-range order and remote disorder, the structural defects in the glass have little effect on the properties of the glass and are easy to eliminate, so it is easy to obtain a working substance with uniform properties on the isotropic and large volume. . Since bismuth glass can generate laser light at room temperature, the temperature quenching effect is small, and the quantum efficiency of the optical pump absorption effect string and luminescence is currently the main laser glass. The laser glass consists of two parts, a matrix glass and an activated ion. The various physicochemical properties of laser glass are mainly determined by the matrix glass, and its spectral properties are mainly determined by the activated ions. However, the matrix glass and the activating ions interact with each other, so the activation ions have a certain influence on the physicochemical properties of the laser glass, and the influence of the matrix glass on its spectral properties is sometimes quite important. As the matrix glass of laser glass, optical glass is mostly used at present, but it is not suitable for any kind of optical glass to be used as laser glass. What are the basic requirements for laser glass? The following are summarized: (1) The illuminating mechanism that activates ions must have metastable state to form a three-level or four-energy vertical mechanism; and it is required that the metastable state has a long life, so that the number of particles is easy to accumulate and reverse. In order to make the laser glass have higher efficiency and low oscillation value, the four-level is superior to the three-level in terms of the energy level mechanism. When the energy interval between the final state and the ground state is greater than 1000 cm-1, the final energy level is almost empty at room temperature. Therefore, pumping at room temperature is also prone to particle number inversion. At present, various activated ions of laser light have been generated in the glass, preferably Nd3+ ions, which are four-level mechanisms, and the distance between the final state of the laser transition and the ground state energy level is about 1950 cm. (2) Laser glass must have a variety of spectral properties. Including the absorption spectrum properties, it is required to have a wide and many absorption bands in the radiant light of the excitation source, a high absorption coefficient, and the absorption band and the peak of the radiation band of the light source overlap as much as possible, which is beneficial to make full use of the excitation light source. Energy; fluorescence spectral properties, generally require that its fluorescence band is small and narrow, so that the output energy is not dispersed; at the same time, in order to convert the absorbed excitation light energy into laser energy as much as possible, the quantum efficiency of fluorescence is required to be as high as possible. The internal energy loss is as small as possible. (3) The laser matrix glass must have good transparency, especially the absorption of the laser wavelength should be as low as possible. The high transparency of the matrix glass allows the energy of the optical pump to be sufficiently absorbed by the activated ions to be converted into a laser. The reduced transparency increases the absorption of the optical pump energy by the substrate and increases the temperature of the laser glass, which brings a series of disadvantages. At present, the radiation band of the optical pump is mostly located in the visible light and near ultraviolet and infrared regions, so it is necessary to select a material that is transparent in this region. It is preferred to use an oxide and a fluoride glass in the inorganic glass. 3. A matrix metal containing a transition metal element such as iron, copper, lead, manganese, diamond, or nickel. Strong absorption in the near ultraviolet to infrared will reduce the transparency of the matrix glass. The main source of laser wavelength absorption in glass is impurities. (4) Laser glass must have good optical uniformity. The optical non-uniformity of the laser glass causes the light wave to deform and generate a path difference after passing through the glass, which causes the oscillation threshold to improve the efficiency and the divergence angle to increase. (5) Laser glass must have good thermal stability. During operation of the laser, the non-radiative transition loss of the activated ions and a portion of the optical energy of the ultraviolet and infrared absorption light pump of the matrix glass are converted into thermal energy that raises the temperature of the glass. At the same time, temperature gradients occur in the radial direction of the rod due to differences in endothermic and cooling conditions. In addition to causing a decrease in the optical uniformity of the laser glass to affect the laser performance, these factors may even cause the laser to be damaged by the poor thermo-mechanical properties of the glass. (6) Laser glass must have good physical and chemical properties. In addition to the above requirements, in order to facilitate the manufacture, processing and use, laser glass is also required to have good physical properties. This includes a small tendency to devitrification and high chemical stability. Have a certain mechanical strength and good light stability and thermal conductivity. Glass having a high degree of devitrification tends to cause glass production, especially in the production process of bulk glass, and it is difficult to obtain a glass having high optical uniformity.

A bandpass filter is a filter that can pass a frequency component in a certain frequency range but attenuate other ranges of frequency components to an extremely low level, as opposed to the concept of a bandstop filter. An example of an analog bandpass filter is a resistor-inductor-capacitor circuit (RLC circuit). These filters can also be generated using a low pass filter in combination with a high pass filter. An ideal bandpass filter should have a completely flat passband that is not amplified or attenuated in the passband, and all frequencies outside the passband are completely attenuated. In addition, the transition outside the passband is minimal. The frequency range is complete. In fact, there is no ideal bandpass filter. The filter is not able to completely attenuate all frequencies outside the desired frequency range, especially outside the desired passband, with a range that is attenuated but not isolated. This is commonly referred to as the roll-off phenomenon of the filter and is expressed in dB of the attenuation amplitude per decade. In general, the filter is designed to ensure that the roll-off range is as narrow as possible, so that the performance of the filter is closer to the design. However, as the roll-off range becomes smaller and smaller, the passband becomes flatter and begins to [ripple". This phenomenon is especially noticeable at the edges of the passband, an effect known as the Gibbs phenomenon. In addition to electronics and signal processing, an example of a bandpass filter application is in the field of atmospheric science. A very common example is the use of a bandpass filter to filter weather data over the last 3 to 10 days, so that the data Only the cyclone that is disturbed is retained in the domain. Between the lower shear frequency f1 and the higher shear frequency f2 is the resonant frequency, where the gain of the filter is the largest, and the bandwidth of the filter is the difference between f2 and f1. Detailed frequency of the bandpass filter Bandpass is to pass a certain range of frequencies and filter out the remaining frequencies. For example, a high pass filter + a low pass filter can form a band pass filter. It is broadly divided into an analog bandpass filter and a digital bandpass filter. Analog bandpass filters typically use circuit components (such as resistors, capacitors, and inductors) to form the frequency characteristic circuit we need. The principle of the analog bandpass filter is to configure the capacitance, resistance and inductance parameters so that the analog filter exhibits a small impedance to the fundamental wave and a large impedance to the harmonics, so that when the load current signal passes the simulation The fundamental signal can be extracted when the bandpass filter is used. At present, some active filters use analog circuits to implement a bandpass filter to detect the fundamental component of the load current, and have been applied in practice. However, analog bandpass filters also have some of their own drawbacks. This is because the center frequency of the analog filter is very sensitive to the parameters of the circuit components (such as capacitors, resistors, and inductors). It is difficult to design suitable parameters, and the parameters of the circuit components will change with the interference of the external environment, which will result in The offset of the center frequency affects the accuracy of the filtering results. The digital bandpass filter uses software to implement the above filtering process, which can well overcome the shortcomings of the analog filter. Once the parameters of the digital bandpass filter are determined, there will be no change, as long as the fluctuation frequency of the grid is designed in our design. Within the scope of the range, the fundamental component can be extracted better. Digital filters can be classified into IR type and FIR type according to their types. The PIR type has only zero point, and it is not easy to obtain better passband and stopband characteristics like the IR type. Therefore, the IR type is selected in the general design. The IR type can be further divided into a Butterworth type filter, a Chebyshev type filter, a Chcbyshev type I filter, and an elliptical type filter. In fact, the bandpass filtering we usually say is to pass within the specified frequency range. 1, high pass filter + low pass filter = band pass filter 2, high resistance filter + low resistance filter = band pass filter For example: 600H-----5KHZ bandpass filter First make a 600HZ high-pass filter, and then make a 5KHZ low-pass filter to filter the frequency through 600NZ in the high-pass filter, and then filter out the frequency above 5KHZ through the low-pass filter. 600 H----- 5KH Z frequency. The principle of high-impedance filter + low-impedance filter = band-pass filter is the same.

Why do the same focal length lenses also divide the ordinary lens and infrared lens? What is the difference between a normal lens and an infrared lens? Next, we will briefly explain the difference between the two: First of all, the purpose of the two is different: In a monitoring environment that does not require infrared light subsidy, an ordinary lens can be used; in a monitoring environment with infrared light subsidy, an infrared lens is required to have an ideal monitoring effect; of course, an ordinary lens is also used in infrared subsidy. I can see the picture, but the picture will become blurred. I believe everyone has a deep understanding. Second, the prices of the two are different: The price of a professional infrared lens is several times that of a normal lens. Why? Because the use of infrared lenses is clear day and night, the effect is natural and expensive. Finally, let's talk about the reasons why the performance and price are so different: Since the refractive index of glass is different for different wavelengths of light, the position of the focus point will be different. At present, ordinary lenses on the market can collect light with wavelengths of about 250 nm to the same plane, that is, 430~650nm or 650~ Light in the 900nm range can be focused successfully, showing a clear image, which is why the normal lens is clear during the day, the night vision is blurred, or the night vision is clear, and the daytime is blurred. The professional infrared lens uses a special lens to collect light from 430 to 900 nm or even longer to the same plane, so it is clear whether day or night. Due to the special lens material, the cost is naturally high. The professional infrared lens cost is high, and the new problem is coming again. The cost of the machine that everyone is doing is high, and the profit is low. What should I do? The Chinese are very smart. Do a little coating on the lens, correct the light, and the cheap infrared lens will come out. And no matter how good or bad, all are called - infrared lens

Centerless cylindrical grinding It does not have a head frame and tailstock, but the workpiece and the guide wheel support the workpiece, grinding with a grinding wheel. Unintentional grinding method It is composed of three mechanisms: grinding wheel, adjusting wheel and workpiece support. The grinding wheel actually works as grinding. The adjusting wheel controls the rotation of the workpiece and the workpiece feed speed occurs. The workpiece holder is grinding. Hold the workpiece while cutting. The centerless cylindrical grinder has a high productivity and an unwieldy outer cylindrical grinding. It does not have a headstock and a tailstock. Instead, it supports the workpiece by a pallet and a guide wheel and grinds it with a grinding wheel. Unintentional grinding method It is composed of three mechanisms: grinding wheel, adjusting wheel and workpiece support. The grinding wheel actually works as grinding. The adjusting wheel controls the rotation of the workpiece and the workpiece feed speed occurs. The workpiece holder is grinding. Hold the workpiece while cutting. Centerless cylindrical grinders have higher productivity. Used for mass production and easy to automate. Ordinary cylindrical grinding Ordinary cylindrical grinding As shown in the following figure, the workpiece is supported between the head frame of the grinding machine and the tip of the tailstock by using the top holes at both ends of the workpiece. During grinding, the workpiece rotates under the rotation of the spindle, and the grinding wheel performs transverse feeding. Centerless cylindrical grinding Centerless cylindrical grinding It does not have a head frame and tailstock, but the workpiece and the guide wheel support the workpiece, grinding with a grinding wheel. Unintentional grinding method It is composed of three mechanisms: grinding wheel, adjusting wheel and workpiece support. The grinding wheel actually works as grinding. The adjusting wheel controls the rotation of the workpiece and the workpiece feed speed occurs. The workpiece holder is grinding. Hold the workpiece while cutting. Centerless cylindrical grinders have higher productivity. Used for mass production and easy to automate. Characteristics of centerless cylindrical grinding compared to ordinary cylindrical grinding 1. Continuous processing, no need to retract the knife, clamping the workpiece and other short time, high productivity. 2. The bracket and guide wheel positioning mechanism is better than the ordinary cylindrical grinder, the top center, the center frame mechanism to support rigidity, the cutting amount can be larger, and is conducive to the processing of slender shaft type workpieces, easy to achieve high-speed grinding and strong grinding. 3. The centerless cylindrical grinding machine workpiece is positioned on the positioning mechanism by the outer circle. The grinding amount is the margin on the workpiece diameter. Therefore, the wear of the grinding wheel, the compensation of the feeding mechanism and the repeated positioning accuracy of the cutting mechanism error on the diameter of the part. The impact is only half that of an ordinary cylindrical grinder. It does not require a center hole, and it is easy to automate the loading and unloading in advance. 4. Wide grinding wheel centerless grinding machine through the type of mechanism, can increase the amount of processing each time, in the cut into the grinding can be complex shape surface grinding or grinding wheel grinding, high productivity, wide application. 5. Centerless cylindrical grinders have no mechanism for ensuring the relative positional accuracy (coaxiality, verticality, etc.) of grinding surfaces and non-abrasive surfaces, and grinding the circumferentially intermittent outer surfaces is poor. 6. It is easy to produce an odd number of secondary roundness on the ground surface. If it is larger, it often causes the illusion that the measurement size is smaller than the maximum physical size, which affects the assembly quality and work performance. 7. The adjustment of the machine tool is complicated and time-consuming. Each replacement of a different diameter workpiece requires adjustment of the bracket height, distance and related process parameters. Therefore, it is difficult to adjust the technology and it is not suitable for small batches and single pieces of production.

There is a famous saying: optics is the soul of lamps (not optical is the bullet of LED?). What if a lamp has no soul? Then I have to sell hardware, aluminum plate, lamp housing, LED "breaking jin ~" (Cantonese, meaning by weight). So the question is, what do we use to shape the soul of LED lamps? LED common optics are lenses and reflectors. What are their advantages and disadvantages? Xiong Da is here with you: lens The LED lens is divided into a primary lens and a secondary lens. The "lens" we generally refer to is a secondary lens, that is, a light source such as an LED lamp bead or a COB , and is closely combined with it. Different lenses can be used to achieve the desired optical effect, depending on the requirements. The main material of the LED lens on the market today is PMMA. It has good plasticity and high light transmittance (up to 93%). The disadvantage is that the temperature resistance is relatively low, only about 90 degrees. The main secondary lens on the market is generally the internal total reflection design (TIR). The design of the lens is transparent in front of the lens, and the tapered surface can collect and reflect the side light. The overlapping of light can achieve perfect light utilization and beautiful spot effect. The TIR lens has an efficiency of more than 90% and is mainly used in small-angle lamps (beam angle <60°), such as spotlights and ceiling lamps. Figure: LED light passes through the lens path diagram. Reflective cup Usually, the LED light source has an illumination angle of about 120°. In order to achieve the desired optical effect, the lamp sometimes uses a reflector to control the illumination distance, the illumination area, and the spot effect. Figure: The light path of the reflector. Figure: Reflective cup and main spot, side spot. Reflective cup material Metal reflector: It needs to be finished by stamping and polishing process. It has the memory of deformation. It has the advantages of low cost and temperature resistance. It is often used for low-grade lighting requirements. Plastic Reflector: One-time demoulding, high optical precision, invisible memory, moderate cost, often used in high-temperature lighting requirements for low-temperature lighting. And for export companies, plastic cups are easier to pass the safety regulations, aluminum cups are not easy to pass the safety regulations The optical effect and application difference between the lens and the reflector: Figure: The effect of the lens is generally no side spot, the light shape is more beautiful, because the TIR design, the light output efficiency is relatively high. Like the German ERCO, it is more like to use the lens scheme to design the lamps, which can be made smaller! Figure: Reflective cup application in this case. The effect is pretty! This is not easy to achieve with a lens! Usually when the TV series is broadcast here, the music rings, and the ultimate problem of good guys and bad guys comes again: Which lens and reflector are better? This is a mistake that has been wrong. First, you must first understand the requirements. What preconditions do you have and what kind of light effects do you need? Further down, is the realization of such a request, which way is the best solution, sometimes even both, and not only once. Good optics are good as long as they achieve the desired optical effect. Suitable is the best secondary optics!

[ Pacific Security Network News ] Many friends are wondering about this question: Why do the same focal length lenses also divide the ordinary lens and infrared lens? What is the difference between a normal lens and an infrared lens? Next, we will briefly explain the difference between the two: First of all, the purpose of the two is different: In a monitoring environment that does not require infrared light subsidy, an ordinary lens can be used; in a monitoring environment with infrared light subsidy, an infrared lens is required to have an ideal monitoring effect; of course, an ordinary lens is also used in infrared subsidy. I can see the picture, but the picture will become blurred. I believe everyone has a deep understanding. Second, the prices of the two are different: The price of a professional infrared lens is several times that of a normal lens. Why? Because the use of infrared lenses is clear day and night, the effect is natural and expensive. Finally, let's talk about the reasons why the performance and price are so different: Since the refractive index of glass is different for different wavelengths of light, the position of the focus point will be different. At present, ordinary lenses on the market can collect light with wavelengths of about 250 nm to the same plane, that is, 430~650nm or 650~ Light in the 900nm range can be focused successfully, showing a clear image, which is why the normal lens is clear during the day, the night vision is blurred, or the night vision is clear, and the daytime is blurred. The professional infrared lens uses a special lens to collect light from 430 to 900 nm or even longer to the same plane, so it is clear whether day or night. Due to the special lens material, the cost is naturally high. The professional infrared lens cost is high, and the new problem is coming again. The cost of the machine that everyone is doing is high, and the profit is low. What should I do? The Chinese are very smart. Do a little coating on the lens, correct the light, and the cheap infrared lens will come out. And no matter how good or bad, all are called - infrared lens! But what is the effect? How long will the coating take off? Will it be evaporated after being heated? The coating is not so uniform, and sometimes it is blurred. What should I do? Reluctantly use it, don't ask too much for bargains.

How to clean the camera lens cleaning camera lens maintenance tips The lens is the "window of the mind" of the digital camera. The good lens can ensure high-fidelity, high-contrast images. Since the lens of the digital camera is difficult to replace, and the maintenance cost is high, pay attention to keep the lens clean. Become very important. However, after using a digital video camera to go out, the lens of the camera will inevitably be stained with dust and other dirty things. Sometimes, if you use carelessly, you will leave "fingerprints" and other stains on the lens. The layer is very harmful! In general, there is a little dust on the lens that does not affect the quality of the image, but if there are more stains on the lens, we will start cleaning the lens at this time. Camera lens maintenance The correct method should be to first blow off the dust on the lens surface with a blower (also called ear wash). This kind of blow balloon is sold in general photography stores, and the price ranges from a few yuan to several tens of dollars, but Be careful not to use a self-contained compressed air tank. Because the pressure is too high, you may blow dust into the gap of the lens, and do not blow it directly with your mouth. In this case, there will be a lot of saliva particles blowing on the lens surface. Difficult to deal with. If you can't clean the dust on the lens surface with a blower, we can also try to clean the lens with a soft brush. In general, you can remove dust and other dirty things. For stubborn stains, such as finger marks, we need to use suede. , lens cleaning cloth or lens paper with lens cleaning solution for cleaning. When scrubbing, be careful not to squeeze the lens surface hard, because the lens surface is covered with a layer of easily damaged coating, which is easily wiped off by hard cleaning. When buying lens paper, be sure to go to a regular professional photography store to buy it. Don't buy cheap lens paper with cheapness. This lens paper often contains a certain amount of wood pulp, which will seriously damage the lens on the digital camera. Coating, by that time you may be "repented". There is a lot of debate about whether to use lens cleaning fluid to clean the lens. Some inferior brand cleaning fluids do damage the lens. Therefore, we recommend that if you use a tool such as suede to clean the stubborn stains on the lens, you don't have to use it. Cleaning solution, must be careful not to use too much when you use it, and do not put the cleaning solution outside the lens, because some of the cleaning liquid is acetone, it is easy to make the black lens edge fade, serious It will also deform the lens around, remember to remember! In addition, we recommend that the time to clean the lens should not exceed 30 seconds, because too long wiping will cause unnecessary damage to the lens, and if so, it will not be worth the loss. In short, cleaning the lens is a delicate work, we must be careful, and we must pay attention to the daily maintenance of the digital camera lens, for example, when used in a large wind and sand environment, immediately after the shooting is completed The camera is loaded into the camera bag. When not in use, you should cover the lens cover or install a UV filter to protect the lens. During the shooting, you should also keep your fingers from leaving fingerprints on the lens. [Be careful to make the ship" ! Camera housing maintenance The most important and most routine, be careful when using it. When shooting, be careful not to touch hard objects such as tables, railings, walls, trees, etc. These objects may easily scratch the DV shell and make you feel bad. The solution is to look at the environment before shooting, avoiding leaning the camera near these things in the composition. Here is only from the aspect of DV shell damage, as for the other aspects of the rain and snow weather shooting, the specific aspects of protection will be discussed later. First of all, the rain and snow weather will wet the camera's outer casing, and it is mixed with a lot of sand, so it is easy to damage the camera's outer casing during the wiping process. Usually our cameras must be kept safely, not placed next to corrosive items, because now the camera shell is two kinds, one is plastic, the other is metal, they are easily corroded, causing deformation of the shell material or It is rusty and very unattractive. Do not place your camcorder near objects with obvious edges and corners during storage to prevent accidental contact with these items or cameras, causing collisions and damage to the casing. Zui's good method is also the easiest method, that is, with a suitable camera bag, the camera will be installed in the bag immediately after shooting, and it will be foolproof.

The main advantages of laser glass compared to laser crystals are: (1) Easy to prepare. By applying the process technology for preparing optical glass and improving it, it is possible to obtain a highly transparent and optically uniform glass, which is relatively easy to produce a large-sized work substrate material, and has a low cost, and a large volume and a high density of activated particles are used for high power. And important advantages of high energy lasers. (2) The matrix glass is easy to change. The composition and properties of the matrix glass vary widely, and the types and amounts of activators added are not limited, so it is easy to develop into a series of laser glass varieties with various characteristics. (3) Easy molding processing. Using optical glass thermoforming and cold working processes, laser glass is easily molded into various shapes, such as rods, sheets, wires, etc., and is ground into high-precision optical surfaces to meet the needs of various device structure developments. (4) Based on the characteristics of the glass structure, that is, short-range order and remote disorder, the structural defects in the glass have little effect on the properties of the glass and are easy to eliminate, so it is easy to obtain a working substance with uniform properties on the isotropic and large volume. . Since bismuth glass can generate laser light at room temperature, the temperature quenching effect is small, and the quantum efficiency of the optical pump absorption effect string and luminescence is currently the main laser glass. The laser glass consists of two parts, a matrix glass and an activated ion. The various physicochemical properties of laser glass are mainly determined by the matrix glass, and its spectral properties are mainly determined by the activated ions. However, the matrix glass and the activating ions interact with each other, so the activation ions have a certain influence on the physicochemical properties of the laser glass, and the influence of the matrix glass on its spectral properties is sometimes quite important. As the matrix glass of laser glass, optical glass is mostly used at present, but it is not suitable for any kind of optical glass to be used as laser glass. What are the basic requirements for laser glass? The following are summarized: (1) The illuminating mechanism that activates ions must have metastable state to form a three-level or four-energy vertical mechanism; and it is required that the metastable state has a long life, so that the number of particles is easy to accumulate and reverse. In order to make the laser glass have higher efficiency and low oscillation value, the four-level is superior to the three-level in terms of the energy level mechanism. When the energy interval between the final state and the ground state is greater than 1000 cm-1, the final energy level is almost empty at room temperature. Therefore, pumping at room temperature is also prone to particle number inversion. At present, various activated ions of laser light have been generated in the glass, preferably Nd3+ ions, which are four-level mechanisms, and the distance between the final state of the laser transition and the ground state energy level is about 1950 cm. (2) Laser glass must have a variety of spectral properties. Including the absorption spectrum properties, it is required to have a wide and many absorption bands in the radiant light of the excitation source, a high absorption coefficient, and the absorption band and the peak of the radiation band of the light source overlap as much as possible, which is beneficial to make full use of the excitation light source. Energy; fluorescence spectral properties, generally require that its fluorescence band is small and narrow, so that the output energy is not dispersed; at the same time, in order to convert the absorbed excitation light energy into laser energy as much as possible, the quantum efficiency of fluorescence is required to be as high as possible. The internal energy loss is as small as possible. (3) The laser matrix glass must have good transparency, especially the absorption of the laser wavelength should be as low as possible. The high transparency of the matrix glass allows the energy of the optical pump to be sufficiently absorbed by the activated ions to be converted into a laser. The reduced transparency increases the absorption of the optical pump energy by the substrate and increases the temperature of the laser glass, which brings a series of disadvantages. At present, the radiation band of the optical pump is mostly located in the visible light and near ultraviolet and infrared regions, so it is necessary to select a material that is transparent in this region. It is preferred to use an oxide and a fluoride glass in the inorganic glass. 3. A matrix metal containing a transition metal element such as iron, copper, lead, manganese, diamond, or nickel. Strong absorption in the near ultraviolet to infrared will reduce the transparency of the matrix glass. The main source of laser wavelength absorption in glass is impurities. (4) Laser glass must have good optical uniformity. The optical non-uniformity of the laser glass causes the light wave to deform and generate a path difference after passing through the glass, which causes the oscillation threshold to improve the efficiency and the divergence angle to increase. (5) Laser glass must have good thermal stability. During operation of the laser, the non-radiative transition loss of the activated ions and a portion of the optical energy of the ultraviolet and infrared absorption light pump of the matrix glass are converted into thermal energy that raises the temperature of the glass. At the same time, temperature gradients occur in the radial direction of the rod due to differences in endothermic and cooling conditions. In addition to causing a decrease in the optical uniformity of the laser glass to affect the laser performance, these factors may even cause the laser to be damaged by the poor thermo-mechanical properties of the glass. (6) Laser glass must have good physical and chemical properties. In addition to the above requirements, in order to facilitate the manufacture, processing and use, laser glass is also required to have good physical properties. This includes a small tendency to devitrification and high chemical stability. Have a certain mechanical strength and good light stability and thermal conductivity. Glass having a high degree of devitrification tends to cause glass production, especially in the production process of bulk glass, and it is difficult to obtain a glass having high optical uniformity.

Before introducing the difference between the imaging properties of concave mirrors and convex mirrors, the concepts of concave mirrors and convex mirrors are known. Concave mirrors are reflection imaging. A mirror (including a convex mirror) is not an instrument that transmits light but is reflected back to the image, and the light follows the law of reflection. This type of mirror is called "convergence" because they tend to collect the light that strikes the surface, and the parallel incident light will be re-aggregated at the focus, also because the normal direction of each point on the surface is different and the light is different. Angle reflection. The concave mirror not only converges the parallel rays of light into the focus, but also reflects the light emitted by the focus into parallel light. Convex mirror imaging is an optical law. Parallel rays are projected onto the convex mirror, and the reflected light will become scattered light. If it extends in the opposite direction of the reflected light to the back of the convex mirror, it can converge and intersect at one point. This is the main focus of the convex mirror (F ), is a virtual focus. The difference between the imaging properties of concave mirror and convex mirror The convex lens is an image formed by refraction and can be positive or negative; virtual, real; Concentration The concave mirror is a reflection image which can be a real image or a virtual image, and can be an enlarged, equal, and reduced image. The astigmatism lens (including the convex lens) is an instrument that transmits light and uses light to fold and image. The light obeys the law of refraction. A mirror (including a convex mirror) is not an instrument that transmits light but is reflected back to the image, and the light follows the law of reflection. The convex lens can be an inverted magnified, equal-sized, reduced real image or an erect magnified virtual image. Parallel light can also be concentrated to refract light from the focus into parallel light. The convex mirror can only be a virtual image that is erect and narrow, mainly for expanding the field of view.

China's CCTV lens market is a huge market, attracting the attention of countless world-class lens manufacturers. Many years ago, the Chinese CCTV lens market was mainly based on Japanese Seiko lenses. As long as it was engaged in the CCTV monitoring industry, few people did not know Seiko. Before 1999, the Chinese market can say that more than 70% of imported CCTV lenses are Seiko lenses, and most of the domestic lenses are mainly imitation Seiko products. But in recent years, the market pattern has changed. Because CCTV Seiko has implemented a general agency system in China, there are countless agents at all levels in the country, and this has led to the subsequent emergence of a large number of imitation Seiko CCTV cameras on the market, making it difficult for users to distinguish between authenticity and counterfeiting. The reputation of Seiko lenses in the Chinese market has been damaged to some extent. At the same time, Japan's Tamron and computar's market share has steadily increased, computar entered the Chinese market in 1996, and CBC Hong Kong is responsible for its sales in China. Because the manufacturers directly participate in market sales and management, the market system is relatively complete. In 1997, Tamron Japan Co., Ltd. started to set up a factory in Foshan, China to achieve local production. In 2002, it established a firm in Shanghai to achieve localized market operations. Up to now, the Foshan factory has grown to more than 3,000 people, and it has become another global production base of Tamron in addition to three production centers in Japan. Tamron is arguably the most successful lens manufacturer to enter the Chinese market. Tenglong Co., Ltd. has a 55-year history of lens production. This [plant age" is almost [young" with the old CCTV lens manufacturer, but its achievements in the field of CCTV lenses have made its position in the industry rise rapidly. Tamron's rapid rise was mainly because they had a major breakthrough in CCTV lens manufacturing technology. They mastered two core industry-leading core technologies: First, Tamron Tamron has mastered aspherical lens manufacturing technology and formed aspherical surfaces. Lens from the design to the processing of leading edge; Second, Tamron Tamron company can design and process ultra-high-precision molds, and can complete the injection pressure control pressure and mature condensing temperature control process, processing a variety of high precision Engineering plastic molding accessories and products. There are only a handful of companies in the world that can master the two core technologies at the same time, and this alone is enough to enable Tamron to win its place in the optical industry in Japan and even in the world. According to the introduction of the general manager of Changchun East Asia Optical Co., Ltd. Shenzhen Branch Zhijun Hou, the general spherical CCTV technology has been developed for more than 100 years, basically the manufacturer can produce as long as the equipment, the relative technical content is not too high. However, as a revolutionary lens manufacturing technology, aspheric technology is still only controlled by a few manufacturers. According to Kong Lingjun, sales promotion director of Tenglong Shanghai Office, in Japan, many companies (such as Sony) of the same age as Tamron have grown into diversified and global companies, but Tamron only focuses on the optical field. Because Tenglong is very focused, they want to be professional, refined and transparent in the optical field. Tamron also does OEM, but customers are absolutely world-class companies and first-rate brands. At present, the smallest and lightest lens in the world is made by Tamron. This lens has recently taken a distance of only 49cm to meet the needs of macro photography. Tamron`s success in China has attracted the attention of other lens manufacturers in Japan. Some Japanese manufacturers are trying to take the path of the Dragon and hope to achieve localized production in China, so as to seize the larger market "cake." To date, Japanese lenses represented by Seiko, Tamron, Computar, FUJINON, Tokina, etc. still account for over 60% of the Chinese lens market. At the same time, China`s CCTV lens manufacturers are also rapidly emerging. Chinese lens manufacturers represented by Fujian have made breakthroughs in the quality and quality of Chinese lenses through the introduction of advanced technologies and equipment, and the market share has steadily increased. Rising, which has caused a lot of impact on Japanese lens manufacturers. Chen Jinfa, general manager of Fuzhou Hongguang Electronic Technology Co., Ltd., said that in a few years, the Chinese lens will occupy more than 50% of the Chinese home market. The South Korean CCTV lens, like the Chinese lens, has risen rapidly in recent years and has become a force that cannot be ignored. Both the quality and the price of Korean lenses lie between Japanese and Chinese shots. Their production CCTV cost and price are lower than Japan, higher than China, and the quality is close to Japan. This point there is a certain gap between Chinese lens manufacturers. Although the Korean lens is also very active in the international market, the advantage in the Chinese market is not particularly obvious. It may be that South Korean manufacturers do not pay enough attention to the Chinese market. According to Chen Jinfa, general manager of Fuzhou Hongguang Electronic Technology Co., Ltd., the world's CCTV lens market is currently dominated by Japan, South Korea, and China, with the exception of Japan and South Korea. China has a complete range of CCTV lenses. Compared with Chinese manufacturers, the varieties of Korean CCTV lenses are not very complete, and not many well-known brands, but occupy a certain share in the international market. The South Korean lens is slightly better than China, but China will soon catch up. Now it can be said that it is close to South Korea, especially the night-vision lens. China has surpassed South Korea and is approaching Japan. In recent years, Japan's CCTV lens has begun to weaken in certain markets, and many international buyers have begun to gravitate towards purchasing inexpensive Chinese shots. However, unlike the Chinese manufacturers, Korean companies have more "team spirit" and are led by industry associations. Both price and market competition are relatively standardized and rational. This is worth learning from domestic companies. Taiwan's CCTV lens manufacturers can not be ignored, the world's largest CCTV lens manufacturers are not in Germany, Japan and South Korea, but in Taiwan - Taiwan Asia Optical currently has more than 30,000 employees, regardless of scale or output in the world the first. However, like many Taiwanese companies, although Taiwanese lens manufacturers also have their own brands, they are mainly OEMs for the world-famous CCTV brands. Therefore, we do not see many Taiwanese brands in the market. As a big lens manufacturing country, the German lens manufacturers will not sit back and watch the CCTV lens market uninteresting. Some German manufacturers have started to plan to enter the monitoring industry and share the CCTV lens cake. Some manufacturers began to visit places such as China, South Korea and the United States, trying to develop, develop and produce high-end CCTV optical lenses through cooperation with local companies. The Japanese lens is mainly dominated by the high-end market, which accounts for a large share of the high-end market. China-made lenses mainly focus on the low-end market. The Chinese lens has low prices because of low production costs (mainly raw materials and labor). The products are suitable for the features, products are welcomed by many domestic and foreign camera manufacturers. Many Chinese lens manufacturers have also begun to realize in recent years that in order to obtain greater profits and the long-term development of the company, it is necessary to open up to the high-end market, and to focus on changing the Chinese lens is equivalent to the image of the low-end lens. For CCTV lens manufacturers in China, they should jump out of the "quagmire" of price wars, work hard, introduce advanced technology and equipment, improve quality and management, shape CCTV brand, increase the added value of products, gradually enter the high-end market, and actively Participate in international competition, win the due market share by fighting. In this regard, many Chinese lens manufacturers are full of confidence.