A high-brightness extended target simulator and method of use

Abstract

The application relates to a high-brightness extended target simulation device and a use method thereof, and belongs to the technical field of optics. The device comprises an extended target simulation assembly and a Fresnel lens. The extended target simulation assembly comprises a plurality of light-emitting light sources, and the extended target simulation assembly is located at a focal plane of the Fresnel lens, is used for simulating and generating an extended target light beam with the same shape as a target, and the Fresnel lens collimates the extended target light beam. The collimated extended target light beam is transmitted to a telescopic detection system. The application can solve the technical problems that the prior art has the problems of insufficient target brightness, difficulty in detection and limitation of a traditional illumination mode.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of optical technology, and particularly relates to a high-brightness extended target simulation device and a use method thereof. BACKGROUND

[0002] In the field of optical detection of targets at a distance of kilometers, the problem of insufficient target brightness often arises, which makes it difficult to effectively detect and identify the target. The main reasons for insufficient target brightness include environmental factors such as atmospheric scattering, atmospheric turbulence, and dark sky background. These factors can significantly reduce the strength of the target signal received by the detection system, thereby affecting the imaging quality and detection accuracy and hindering the development of related technical research and experimental verification work.

[0003] To solve the above problem, the existing technology usually uses the method of adding an illumination light source to enhance the target brightness. For example, by deploying a high-power laser or strong light LED illumination system, the target area is actively irradiated during the detection process to improve the contrast between the target and the background. However, this scheme has several obvious defects: on the one hand, the newly added illumination device increases the overall complexity of the system, and increases the difficulty of use and maintenance cost; on the other hand, the traditional illumination method can only illuminate targets of fixed shape and size, and lacks flexibility, which cannot meet the needs of diversified test scenarios. SUMMARY

[0004] In view of the various deficiencies of the prior art, the present application provides a high-brightness extended target simulation device and a use method thereof to solve the technical problems of insufficient target brightness leading to detection difficulties and limitations of traditional illumination methods in the prior art.

[0005] To achieve the above purpose, the present application provides the following technical solutions:

[0006] In a first aspect, the present application provides a high-brightness extended target simulation device, comprising an extended target simulation assembly and a Fresnel lens, the extended target simulation assembly comprising a plurality of light sources, and the extended target simulation assembly being located at the focal plane of the Fresnel lens, for simulating and generating an extended target beam identical in shape to the target, and the Fresnel lens collimating the extended target beam, and the collimated extended target beam being transmitted to a telescopic detection system.

[0007] The present technical solution is further provided, wherein the plurality of light sources are arranged at equal intervals to form a two-dimensional array, and the light sources in the two-dimensional array are selectively lit to generate the extended target beam according to the target shape.

[0008] The present technical solution is further provided, wherein the diameter of the light source is , and the distance between adjacent light sources is , satisfying:

[0009] ;

[0010] ;

[0011] Wherein, s is the pixel size of the telescope detection system, F is the equivalent focal length of the telescope detection system, L is the focal length of the Fresnel lens, and n is the number of pixels occupied by the imaging of a single light source.

[0012] The technical solution is further provided that the light source includes an incoherent light source or a coherent light source, and the wavelength is adapted to the response waveband of the telescope detection system.

[0013] The technical solution is further provided that it further includes a beacon laser, the beacon laser outputs a beacon light beam for alignment with the telescope detection system, the light outlet of the beacon laser is located at the focal plane of the Fresnel lens, and the optical axis of the beacon laser is parallel to the optical axis of the Fresnel lens.

[0014] The technical solution is further provided that it further includes an adjustable base, the extended target simulation assembly, the Fresnel lens, and the beacon laser are all arranged on the adjustable base, and the adjustable base has the functions of adjusting the pitch angle and the azimuth angle.

[0015] The technical solution is further provided that the diameter of the Fresnel lens matches the entrance pupil diameter of the telescope detection system.

[0016] In the second aspect, the application provides a use method of the high-brightness extended target simulation device, including the following steps:

[0017] S100, performing gray-scale processing on the target image to be simulated;

[0018] S200, dividing the target image to be simulated after the gray-scale processing into a plurality of sub-image blocks, and each sub-image block corresponds to a light source in the extended target simulation assembly;

[0019] S300, starting the beacon laser and adjusting the pitch angle and the azimuth angle of the beacon laser so that the beacon light beam enters the field of view of the telescope detection system;

[0020] S400, turning on the light source corresponding to the sub-image block to generate an extended target light beam, and transmitting the extended target light beam to the telescope detection system after collimation by the Fresnel lens.

[0021] The technical solution is further provided that in step S200, the size of the target image to be simulated is MxN, the size of a single light source is nxn, if M and N can be divided by n, the image is directly divided; if M and N cannot be divided by n, the size of the target image to be simulated needs to be expanded to the minimum integer multiple value to form an extended target image before image division.

[0022] The technical solution is further provided that in step S400, the driving current of each light emitting source is calculated to form a current matrix, the current matrix is loaded to the extended target simulation assembly, the light emitting source corresponding to the sub-image block is in an open state, the extended target light beam is generated, and the extended target light beam is transmitted to the telescopic detection system after collimation by the Fresnel lens.

[0023] The beneficial effects of the present application are:

[0024] By changing the combination of light emitting sources, various target forms can be simulated flexibly to generate an extended target light beam corresponding to the target; the light emitting source is a self-luminous light source, which ensures sufficient brightness to support the technical research, performance evaluation and verification test of a long-distance optical detection system; the Fresnel lens is used to collimate the extended target light beam, so that most of the light beams can enter the telescopic detection system after long-distance transmission, thereby improving the light beam utilization rate, and the structure is simple, the cost is low, and the use is convenient. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 FIG. 1 is a schematic view of a high-brightness extended target simulation device in an embodiment of the present application;

[0026] Figure 2 FIG. 2 is a schematic view of an extended target simulation assembly simulating a target in an embodiment of the present application;

[0027] Figure 3 FIG. 3 is a flow chart of a use method of a high-brightness extended target simulation device in an embodiment of the present application;

[0028] In the drawings: 1, extended target simulation assembly; 2, Fresnel lens; 3, telescopic detection system; 4, beacon laser; 5, adjustable base; 6, light emitting source; 7, substrate. DETAILED DESCRIPTION

[0029] In order to enable personnel in the art to better understand the technical solutions of the present application, the technical solutions of the present application will be described clearly and completely below in combination with the drawings of the present application. Based on the embodiments in the present application, other similar embodiments obtained by those of ordinary skill in the art without making creative efforts should belong to the scope of protection of the present application. In addition, the directional words mentioned in the following embodiments, such as “up”, “down”, “left”, “right”, etc., are only reference directions of the drawings, and therefore, the directional words used are used to illustrate but not to limit the present application.

[0030] Embodiment one:

[0031] According to the embodiment of the present application, a high-brightness extended target simulation device is provided, please refer to Figures 1 to 2, including an extended target simulation assembly 1 and a Fresnel lens 2, the extended target simulation assembly 1 includes a plurality of light sources 6, and the extended target simulation assembly 1 is located at the focal plane of the Fresnel lens 2, for simulating and generating an extended target light beam with the same shape as the target, and the Fresnel lens 2 collimates the extended target light beam, and the collimated extended target light beam is transmitted to a telescopic detection system 3.

[0032] It can be understood that the extended target simulation assembly 1 is placed at the focal plane of the Fresnel lens 2, and the extended target light beam generated by the extended target simulation assembly 1 realizes beam collimation after passing through the Fresnel lens 2, and the collimated light beam is transmitted for a long distance of several kilometers into the telescopic detection system 3, and the collimated transmission ensures that most of the light beam generated by the extended target simulation assembly 1 can enter the telescopic detection system 3.

[0033] In a high-brightness extended target simulation device according to the embodiment, please refer to Figures 1 to 2 , the extended target simulation assembly 1 further includes a substrate 7, and a plurality of light sources 6 are arranged on the substrate 7 at equal intervals and form a two-dimensional array, and the light sources 6 in the two-dimensional array are selectively lit according to the target shape to generate an extended target light beam.

[0034] It can be understood that the two-dimensional light array formed by the equal-interval vertical arrangement and the selective lighting of the light sources 6 in the specific area according to the shape of the target to be simulated enable the device to simulate targets with different shapes and sizes. This design greatly improves the flexibility and adaptability of the device and can meet the needs of various test scenarios. Since self-luminous light sources are used, sufficient brightness can be ensured, and the problem of insufficient target brightness caused by factors such as atmospheric scattering and atmospheric turbulence in traditional methods is overcome, which is beneficial to long-distance detection. The use of the Fresnel lens 2 for collimating the generated light beam simplifies the system structure and reduces the cost.

[0035] Further, the light sources 6 include incoherent light sources or coherent light sources, providing more choices for different application scenarios. The wavelength of the light sources 6 is adapted to the response band of the telescopic detection system 3, and the power is in the order of hundreds of milliwatts.

[0036] It can be understood that the wavelength of the light-emitting light source 6 is adapted to the response band of the telescopic detection system 3, which ensures that the extended target light beam can be optimally imaged and detected in the telescopic detection system 3, which means that no matter the telescopic detection system 3 works in visible light, infrared or other specific wave bands, a suitable light-emitting light source 6 can be found to simulate the target, thereby improving the versatility and application range of the entire device. At the same time, selecting a light source wavelength matched with the response band of the telescopic detection system 3 can maximize the use of the sensitivity of the telescopic detection system 3, improve the quality and intensity of the received signal, which is particularly important for high-precision target detection in complex environmental conditions (such as atmospheric scattering, atmospheric turbulence, etc.).

[0037] In a high-brightness extended target simulation device according to the embodiment, please refer to Figures 1 to 2 , in order to ensure that the extended target light beam generated by the extended target simulation assembly 1 can form a clear and non-coherent image on the camera of the telescopic detection system 3, the diameter and spacing of the light-emitting light source 6 and the configuration of the telescopic detection system 3 need to meet the following relationship:

[0038] The diameter of the light-emitting light source 6 is , the spacing between adjacent light-emitting light sources 6 is , then:

[0039] ;

[0040] ;

[0041] wherein s is the pixel size of the telescopic detection system 3, F is the equivalent focal length of the telescopic detection system 3, L is the focal length of the Fresnel lens 2, and n is the number of pixels occupied by the imaging of a single light-emitting light source. By setting the above relationship, it is ensured that each light-emitting light source 6 neither overlaps too much so that their images overlap on the camera of the telescopic detection system 3, nor disperses too much to cause resolution to decrease.

[0042] It is worth noting that, in order to ensure that adjacent light-emitting light sources 6 are not coherent and not continuous in the detection image of the telescopic detection system 3, should be much smaller than the diameter . Specifically, through the fusion of geometric optics constraints and sampling theorem, the safety design margin of the parameter is selected in actual application.

[0043] In a high-brightness extended target simulation device according to the embodiment, please refer to Figures 1 to 2 , it further comprises a beacon laser 4, which outputs a beacon light beam for alignment with the telescopic detection system 3. It can be understood that the introduction of the beacon light beam makes the alignment process of the telescopic detection system 3 more convenient and accurate.

[0044] Further, the light outlet of the beacon laser 4 is located at the focal plane of the Fresnel lens 2, and the optical axis thereof is parallel to the optical axis of the Fresnel lens 2, the beacon light beam is visible light, and the beacon light beam does not pass through the Fresnel lens 2.

[0045] It can be understood that this structural design ensures that the beacon laser 4 serves as an independent, highly collimated light source, and the beacon light beam can still maintain a small divergence angle and a high energy density after long-distance transmission, facilitating accurate alignment between the telescopic detection system 3 and the device. At the same time, the beacon light beam is not affected or interfered by the Fresnel lens 2, ensuring that the characteristics and performance of the beacon light beam are not affected, which is particularly important for application scenarios that require high-precision alignment. In addition, since the beacon light beam is visible light, it can be easily identified and fine-tuned by the naked eye even in daylight or complex background conditions, facilitating the user to debug and maintain the entire system during actual operation, and reducing the operation difficulty and technical requirements.

[0046] Specifically, the beacon light beam is a fine light beam laser with a small divergence angle, which ensures that the beacon light beam has a small divergence angle and a small light pupil after long-distance free transmission to the telescopic detection system 3, and the light intensity energy meets the naked eye observation, facilitating the alignment of the optical axis of the device with the telescopic detection system 3. Preferably, the divergence angle is within a few milliradians.

[0047] Specifically, the beacon laser 4 is connected with the base plate 7 through an L-shaped bracket, the vertical side of the L-shaped bracket is detachably connected with the base plate 7, and the horizontal side of the L-shaped bracket bears the beacon laser 4. The optical axis of the beacon laser 4 is initially parallel to the optical axis of the Fresnel lens 2, the entrance of the light blocking cylinder is located at the focal plane of the Fresnel lens 2, the beacon light beam passes through two 45° reflecting mirrors placed in parallel, the horizontal translation of the beacon light optical axis is realized, and the beacon light beam does not pass through the Fresnel lens 2. In terms of structure, the light beam is deviated through the light blocking cylinder, and the installation reference of the beacon laser 4 is a parallel relationship. Through the initial parallel calibration + mechanical deflection structural design, the basic parallel relationship between the beacon light beam and the main optical axis is met, and spatial avoidance is also realized.

[0048] In one high-brightness extended target simulation device in the embodiment, please refer to Figures 1 to 2 Further, the adjustable base 5 is provided with pitch angle and azimuth angle adjustment functions.

[0049] Further, the adjustable base 5 has a pitch adjustment shaft and an azimuth adjustment shaft perpendicular to each other, which are used for adjusting the spatial direction of the device. The pitch adjustment shaft is arranged horizontally and is driven by a first driving motor, and the azimuth adjustment shaft is arranged vertically and is driven by a second driving motor.

[0050] In a high-brightness extended target simulation device of the embodiment, referring to Figures 1 to 2 , the diameter of the Fresnel lens 2 matches the entrance pupil diameter of the telescopic detection system 3, and the light beam collimated by the Fresnel lens 2 can enter the telescopic detection system 3 as much as possible, thereby reducing the energy loss caused by beam truncation and improving the light energy utilization.

[0051] Embodiment two:

[0052] The application provides a use method of a high-brightness extended target simulation device, referring to Figures 1 to 3 , comprising the following steps:

[0053] S100, performing gray-scale processing on the target image to be simulated;

[0054] S200, dividing the target image to be simulated after the gray-scale processing into a plurality of sub-image blocks, and each sub-image block corresponds to one light source 6 in the extended target simulation assembly;

[0055] S300, starting the beacon laser 4, and adjusting the pitch angle and the azimuth angle of the beacon laser 4 so that the beacon light beam enters the field of view of the telescopic detection system 3;

[0056] S400, turning on the light source 6 corresponding to the sub-image block to generate an extended target light beam, and transmitting the extended target light beam to the telescopic detection system 3 after collimation by the Fresnel lens 2.

[0057] Further, in step S100, the target image to be simulated (which can be in RGB or RAW format) is converted into a gray-scale image sequence for gray-scale processing.

[0058] Further, in step S200, the size (imaging pixel number) of the target image to be simulated is M×N, and the size (imaging pixel number) of a single light source 6 is n×n. If M and N can be divided by n, the image is directly divided; if M and N cannot be divided by n, the size of the target image to be simulated needs to be expanded to the minimum integer multiple value to form an extended target image before image division, and the size of the extended target image is M'×N'. It should be noted that the expansion adopts a two-stage expansion strategy, including size expansion and symmetric padding.

[0059] Firstly, size expansion can solve the non-integer multiple contradiction between the size (M rows×N columns) of the original image and the size (n×n) of the light source array control unit, and realize accurate matching of image data and hardware driving:

[0060] ;

[0061] ;

[0062] The gray scale value of the extended area is filled with 0, and the row and column directions are symmetrically divided.

[0063] In the second aspect, white pixels are added in the extended area, and meanwhile, the image is kept in the center of the field of view to avoid target deviation caused by expansion.

[0064] Taking the row direction as an example, the total number of rows to be expanded is , wherein, represents the remainder of M divided by n. If is even, the image is expanded by rows upwards and downwards; if is odd, the image is expanded by rows upwards and rows downwards. It should be noted that the upward and downward expansion means that white rows are added at the top and bottom of the image to form an extended area, and the gray scale value of the extended area is set to 0 (corresponding to the extinguished state of the light source). The column direction is processed in the same way and will not be described again.

[0065] For example, M = 100, N = 200, n = 16, and the row expansion is calculated as follows:

[0066] , , 6 rows are expanded upwards and 6 rows are expanded downwards, i.e. .

[0067] Further, if M and N can be divided by n, the target image is divided into sub-image blocks; if M and N cannot be divided by n, the expanded target image is divided into sub-image blocks. It should be noted that the size of each sub-image block is n x n.

[0068] Further, in step S400, the light source 6 corresponding to the sub-image block is turned on, specifically including the following steps:

[0069] S401, calculate the driving current I of each light source 6 to form a current matrix:

[0070] ;

[0071] wherein, ADU Ave represents the average gray scale value of the sub-image block, ADU Max represents the maximum gray scale value, and I Max represents the rated maximum current of the light source.

[0072] S402, load the current matrix to the extended target simulation component 1, cause the light emitting light source 6 corresponding to the sub-image block to be in an open state, generate an extended target light beam, and the extended target light beam is transmitted to the telescopic detection system 3 after being collimated by the Fresnel lens 2.

[0073] In summary, by changing the combination form of the light emitting light source 6 in the open state, various target forms can be flexibly simulated, and the extended target light beam corresponding to the target is generated. Please refer to Figure 2 , the extended target light beam is "1".

[0074] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily limit to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0075] Alternatively, the specific examples in the present embodiment can refer to the examples described in the above embodiments, and the present embodiment will not be described here.

[0076] The serial numbers of the above embodiments of the present application are only for description, not representing the advantages and disadvantages of the embodiments.

[0077] In the above embodiments of the present application, the description of each embodiment has its own emphasis, and the parts not described in detail in a certain embodiment can refer to the relevant description of other embodiments.

[0078] The above is only the preferred embodiment of the present application, and it should be pointed out that for ordinary skilled in the art, without departing from the principle of the present application, a number of improvements and refinements can be made, which should be considered as the protection scope of the present application.

Claims

1. A high-brightness extended target simulation device, characterized in that, The system includes an extended target simulation component, a Fresnel lens, and a beacon laser. The extended target simulation component includes several light sources and is located at the focal plane of the Fresnel lens. It is used to simulate and generate an extended target beam with the same shape as the target. The Fresnel lens collimates the extended target beam, and the collimated extended target beam is transmitted to the telescope detection system. Several light sources are arranged in a two-dimensional array at equal intervals. According to the shape of the target, the light sources in the two-dimensional array are selectively lit to generate an extended target beam. The light sources include incoherent light sources or coherent light sources, and their wavelengths are adapted to the response band of the telescope detection system. The beacon laser outputs a beacon beam for alignment with the telescope detection system. The output port of the beacon laser is located at the focal plane of the Fresnel lens, and the optical axis of the beacon laser is parallel to the optical axis of the Fresnel lens. The extended target simulation component, the Fresnel lens, and the beacon laser are all mounted on an adjustable base. The adjustable base has pitch and azimuth adjustment functions, and the diameter of the Fresnel lens matches the entrance pupil diameter of the telescope detection system.

2. The high-brightness extended target simulation device according to claim 1, characterized in that, The diameter of the light source is The spacing between adjacent light sources is ,satisfy: ； ； Where s is the pixel size of the telescope detection system, F is the equivalent focal length of the telescope detection system, L is the focal length of the Fresnel lens, and n is the number of pixels occupied by a single light source.

3. A method of using a high-brightness extended target simulation device, based on the high-brightness extended target simulation device as described in claim 1 or 2, characterized in that, Includes the following steps: S100. Perform grayscale processing on the target image to be simulated; S200. Divide the grayscale processed target image into several sub-image blocks, each sub-image block corresponding to a light source in the extended target simulation component; S300. Activate the beacon laser and adjust its elevation and azimuth angles to bring the beacon beam into the field of view of the telescope detection system. S400: Turn on the light source corresponding to the sub-image block to generate an extended target beam. The extended target beam is collimated by a Fresnel lens and then transmitted to the telescope detection system.

4. The method of using the high-brightness extended target simulation device according to claim 3, characterized in that, In step S200, the size of the target image to be simulated is M×N, and the size of a single light source is n×n. If M and N are divisible by n, image segmentation is performed directly. If M and N are not divisible by n, the size of the target image to be simulated needs to be expanded to its smallest integer multiple before image segmentation to form an expanded target image.

5. The method of using the high-brightness extended target simulation device according to claim 3, characterized in that, In step S400, the driving current of each light source is calculated to form a current matrix. The current matrix is ​​loaded onto the extended target simulation component, causing the light source corresponding to the sub-image block to be turned on, generating an extended target beam. The extended target beam is collimated by a Fresnel lens and then transmitted to the telescope detection system.

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