A method and device for dynamically simulating low-light night vision targets with variable distance and variable spectrum

Abstract

The present invention provides a method and device for dynamically simulating a low-light night vision target with variable distance and variable spectrum, comprising the following steps: S1: The central control computer sends the spectral information of the target to the multi-spectral projection system. S2: The multi-spectral projection system controls the brightness of each LED lamp in the visible light source modulation module. S3: The multi-spectral projection system controls the brightness of each LED lamp in the near-infrared light source modulation module. S4: The central control computer sends the size grayscale image of the target to be simulated to the multi-spectral projection system. S5: The multi-spectral projection system controls the visible light DMD module to output the image. S6: The multi-spectral projection system controls the near-infrared DMD module to output the image. S7: Simulate a low-light night vision target. S8: The central control computer calculates the defocus distance of the wide-spectrum diffuser screen relative to the collimating objective lens, and drives the electric displacement stage to move to the required distance. The present invention improves the simulation degree of night vision target simulation and greatly improves the level of low-light night vision training and detection.

Description

Technical Field

[0001] The present invention mainly relates to the technical field of low-light night vision, and specifically provides a method and device for dynamically simulating low-light night vision targets with variable distance and variable spectrum. Background Art

[0002] Through photoelectric conversion and enhancement, low-light night vision enables humans to see faint light targets that are invisible to the naked eye at night and is widely used in military, security, and other fields. The personnel training, equipment calibration, and other work of low-light night vision usually rely on artificially simulated low-light target sources. Existing simulated low-light target sources can usually only simulate static targets with fixed scenes, fixed distances, fixed spectra, and fixed color temperatures, with low simulation accuracy and a large gap from complex spectral targets in real dynamic scenes. Summary of the Invention

[0003] To address the problem that existing simulated low-light target sources can usually only simulate static targets with fixed scenes, fixed distances, fixed spectra, and fixed color temperatures, with low simulation accuracy and a large gap from complex spectral targets in real dynamic scenes, the present invention provides a method and device for dynamically simulating low-light night vision targets with variable distance and variable spectrum.

[0004] The present invention adopts the following technical solutions:

[0005] A method for dynamically simulating low-light night vision targets with variable distance and variable spectrum, comprising the following steps:

[0006] S1: The central control computer sends the spectral information of the target to be simulated to the multi-spectral projection system, including Information 1: the spectral characteristic curve and illuminance value of the visible light source modulation module, and Information 2: the spectral characteristic curve and illuminance value of the near-infrared light source modulation module.

[0007] S2: The main control board of the multi-spectral projection system controls the brightness of each LED lamp in the visible light source modulation module. The visible light spectrometer and the micro-illuminometer respectively monitor the spectral characteristics and illuminance and feedback the monitoring data to the main control board. The main control board corrects the brightness of each LED lamp according to the monitoring data, thereby fitting a light source that conforms to the visible light spectral characteristic curve given by the central control computer in S1. Finally, through the mixing and uniformizing of light by the integrating sphere, a uniform visible light source that meets the requirements is output from the light outlet of the integrating sphere.

[0008] S3: The main control board of the multi-spectral projection system controls the brightness of each LED lamp in the near-infrared light source modulation module. The near-infrared spectrometer and the micro-irradiance meter respectively monitor the spectral characteristics and irradiance and feedback the monitoring data to the main control board. The main control board corrects the irradiance of each LED lamp according to the monitoring data, thereby fitting a light source that conforms to the near-infrared spectral characteristic curve given by the central control computer in S1. Finally, through the mixing and uniformizing of light by the integrating sphere, a uniform near-infrared light source that meets the requirements is output from the light outlet of the integrating sphere.

[0009] S4: The central control computer sends the size grayscale image of the target to be simulated to the multispectral projection system.

[0010] First, calculate the size information. For targets of the same size, the perceived size by the observer is different at different distances from the observer. The image sizes to be generated on the visible light DMD module and the near-infrared DMD module of the multispectral projection system for the target to be simulated are calculated according to the following formula:

[0011]

[0012] Where:

[0013] D 0 is the size of the target pattern on the DMD module,

[0014] D 1 is the size of the target pattern in the real world,

[0015] L 1 is the distance between the target pattern in the real world and the observer,

[0016] f 1 is the focal length of the collimating objective lens,

[0017] β 1 is the projection magnification of the multispectral projection system;

[0018] Furthermore, calculate the grayscale information of visible light and near-infrared and send it to the multispectral projection system. Information 1: The image grayscale maps of the R channel, G channel, and B channel of visible light. Information 2: The image grayscale map of the near-infrared channel.

[0019] S5: The main control board of the multispectral projection system controls the visible light DMD module according to the given grayscale maps of the R / G / B channels of visible light and outputs the image.

[0020] S6: The main control board of the multispectral projection system controls the near-infrared DMD module according to the given grayscale map of the near-infrared channel and outputs the image.

[0021] S7: After passing through their respective illumination lenses and TIR prisms, the visible light DMD module and the near-infrared DMD module are combined by a beam combining prism to fuse the visible light image and the near-infrared image, and the image is projected onto a wide-spectrum reflective screen through a projection lens, thus simulating a low-light night vision target with a spectral range of 400nm to 1000nm.

[0022] S8: The central control computer calculates the defocus distance of the wide-spectrum diffusive reflection screen relative to the collimating objective lens according to the distance of the target to be simulated, and drives the electric displacement stage to move to the required distance through the motion controller. The calculation is carried out according to the following formula:

[0023]

[0024] Wherein:

[0025] L 1 is the distance between the target pattern in the real world and the observer.

[0026] L 2 is the distance between the wide-spectrum diffusive reflection screen and the focal plane of the collimating objective lens.

[0027] f 2 is the focal length of the collimating objective lens.

[0028] Through the above steps, the dynamic simulation of the distance, size, and spectral characteristics of the low-light target in the real world is realized.

[0029] The present invention further provides a device for dynamic simulation of a low-light night vision target with variable distance and variable spectrum, comprising a collimating objective lens, a multi-spectral projection system, an electric displacement stage, a motion controller, a wide-spectrum diffusive reflection screen, a central control computer, an optical platform, and a support base; the collimating objective lens is used for collimating the low-light target and simulating the distance, the multi-spectral projection system is used for projecting a dynamic low-light pattern with variable spectrum; the wide-spectrum diffusive reflection screen is used for receiving the low-light pattern projected by the multi-spectral projection system; the electric displacement stage can move back and forth along the optical axis direction of the collimating system, and is used for changing the distance between the multi-spectral projection system and the wide-spectrum reflection screen and the collimating system; the motion controller is used for calculating and controlling the forward and backward movement distance and speed of the electric displacement stage; the central control computer is used for controlling the motion controller and the multi-spectral projection system.

[0030] Preferably, the multi-spectral projection system is composed of a main control board, a visible light source modulation module, a visible light illumination lens, a visible light TIR prism, a visible light DMD module, a near-infrared light source modulation module, a near-infrared illumination lens, a near-infrared TIR prism, a near-infrared DMD module, a beam combining prism, and a projection lens.

[0031] Preferably, the visible light source modulation module is composed of an integrating sphere, a visible light spectrometer, a micro-illuminance meter, and a visible light LED lamp group; the visible light LED lamp group has a spectrum in the range of 400nm to 700nm, each LED lamp is a single wavelength, the central wavelength interval is 10nm, and the luminous brightness of each single-wavelength LED lamp can be independently controlled by the main control board of the multi-spectral projection system.

[0032] Preferably, the near-infrared light source modulation module consists of an integrating sphere, a near-infrared spectrometer, a low-light irradiance meter, and a near-infrared LED lamp set. The near-infrared LED lamp set has a spectrum ranging from 700 nm to 1000 nm. Each LED lamp is a single wavelength, with a central wavelength interval of 10 nm. The luminous intensity of each single-wavelength LED lamp can be independently controlled by the main control board of the multi-spectral projection system.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0034] The existing low-light target simulation methods usually use a collimator or a simulation sand table. Their main characteristics are that the target pattern is fixed, the target size is fixed, and usually the distance is also unchangeable. Compared with the above methods, the present invention has variable spectral characteristics, variable distance, and variable size, and can dynamically simulate the low-light targets in the real world. It can be widely used in the detection of low-light night vision goggles, low-light night vision training, and other fields.

[0035] The following will explain and illustrate the present invention in detail in combination with the accompanying drawings and specific embodiments. Description of the Drawings

[0036] Figure 1 is the overall architecture diagram of the present invention;

[0037] Figure 2 is the architecture diagram of the multi-spectral projection system in the present invention;

[0038] Figure 3 is the framework diagram of the visible light source modulation module in the present invention;

[0039] Figure 4 is the framework diagram of the near-infrared light source modulation module in the present invention;

[0040] Figure 5 is the target simulation flow chart of the present invention. Detailed Embodiments

[0041] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant accompanying drawings. Several embodiments of the present invention are given in the drawings, but the present invention can be implemented in different forms and is not limited to the embodiments described in the text. On the contrary, providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0042] It should be noted that when an element is referred to as being "fixed on" another element, it can be directly on the other element or there can be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for the purpose of illustration.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this invention belongs. The terms used in the description of the present invention herein are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0044] Embodiment 1:

[0045] A method for dynamically simulating a low-light night vision target with variable distance and variable spectrum, comprising the following steps:

[0046] S1: The central control computer sends the spectral information of the target to be simulated to the multi-spectral projection system. Information 1, the spectral characteristic curve and illuminance value of the visible light source modulation module; Information 2, the spectral characteristic curve and illuminance value of the near-infrared light source modulation module;

[0047] S2: The main control board of the multi-spectral projection system controls the brightness of each LED lamp in the visible light source modulation module. The visible light spectrometer and the low-light illuminometer respectively monitor the spectral characteristics and illuminance and feedback the monitoring data to the main control board. The main control board corrects the brightness of each LED lamp according to the monitoring data, so as to fit a light source that conforms to the visible light spectral characteristic curve given by the central control computer in S1. Finally, through the mixing and uniformizing of light in the integrating sphere, a uniform visible light source that meets the requirements is output from the light outlet of the integrating sphere;

[0048] S3: The main control board of the multi-spectral projection system controls the brightness of each LED lamp in the near-infrared light source modulation module. The near-infrared spectrometer and the low-light irradiance meter respectively monitor the spectral characteristics and irradiance and feedback the monitoring data to the main control board. The main control board corrects the irradiance of each LED lamp according to the monitoring data, so as to fit a light source that conforms to the near-infrared spectral characteristic curve given by the central control computer in S1. Finally, through the mixing and uniformizing of light in the integrating sphere, a uniform near-infrared light source that meets the requirements is output from the light outlet of the integrating sphere;

[0049] S4: The central control computer sends the size grayscale image of the target to be simulated to the multi-spectral projection system;

[0050] First, solve the size information. For targets of the same size, the perceived size by the observer is different at different distances from the observer. The image size that the target to be simulated should generate on the visible light DMD module and the near-infrared DMD module of the multi-spectral projection system is calculated according to the following formula:

[0051]

[0052] Where:

[0053] D0 is the size of the target pattern on the DMD module,

[0054] D 1 is the size of the target pattern in the real world,

[0055] L 1 is the distance between the target pattern in the real world and the observer,

[0056] f 1 is the focal length of the collimating objective lens,

[0057] β 1 is the projection magnification of the multispectral projection system;

[0058] Furthermore, the gray-scale information of visible light and near-infrared is calculated and sent to the multispectral projection system. Information 1: the gray-scale images of the R channel, G channel, and B channel of visible light, Information 2: the gray-scale image of the near-infrared channel.

[0059] S5: The main control board of the multispectral projection system controls the visible light DMD module according to the given gray-scale images of the visible light R / G / B channels and outputs the image;

[0060] S6: The main control board of the multispectral projection system controls the near-infrared DMD module according to the given gray-scale image of the near-infrared channel and outputs the image;

[0061] S7: After passing through their respective illumination lenses and TIR prisms, the visible light DMD module and the near-infrared DMD module are combined by a beam-combining prism to fuse the visible light image and the near-infrared image, and the image is projected onto a wide-spectrum reflective screen through a projection lens, thus simulating a low-light night vision target with a spectral range of 400nm - 1000nm;

[0062] S8: The central control computer calculates the defocus distance of the wide-spectrum diffusive reflection screen relative to the collimating objective lens according to the distance of the target to be simulated, and drives the electric displacement stage to move to the required distance through the motion controller. The calculation is carried out through the following formula:

[0063]

[0064] Where:

[0065] L 1 is the distance between the target pattern in the real world and the observer,

[0066] L 2 is the distance between the wide-spectrum diffusive reflection screen and the focal plane of the collimating objective lens,

[0067] f 2 is the focal length of the collimating objective lens;

[0068] Through the above steps, the dynamic simulation of the distance, size, and spectral characteristics of low-light targets in the real world is achieved.

[0069] Please refer to the appendix Figure 1 , a device for dynamic simulation of low-light night vision targets with variable distance and variable spectrum, comprising a collimating objective lens, a multi-spectral projection system, an electric displacement stage, a motion controller, a wide-spectrum diffusive reflection screen, a central control computer, an optical platform, and a support base; the collimating objective lens is used for collimating and distance simulation of low-light targets, the multi-spectral projection system is used for projecting dynamic low-light patterns with variable spectra; the wide-spectrum diffusive reflection screen is used for receiving the low-light patterns projected by the multi-spectral projection system; the electric displacement stage can move back and forth along the optical axis direction of the collimating system, and is used to change the distance between the multi-spectral projection system and the wide-spectrum reflection screen and the collimating system; the motion controller is used to calculate and control the forward and backward movement distance and speed of the electric displacement stage; the central control computer is used to control the motion controller and the multi-spectral projection system.

[0070] Please refer to the appendix Figure 2 , the multi-spectral projection system consists of a main control board, a visible light source modulation module, a visible light illumination lens, a visible light TIR prism, a visible light DMD module, a near-infrared light source modulation module, a near-infrared illumination lens, a near-infrared TIR prism, a near-infrared DMD module, a beam-combining prism, and a projection lens.

[0071] Please refer to the appendix Figure 3 , the visible light source modulation module consists of an integrating sphere, a visible light spectrometer, a micro-illuminance meter, and a visible light LED lamp group; the visible light LED lamp group has a spectrum in the range of 400nm - 700nm, each LED lamp is a single wavelength, the central wavelength interval is 10nm, and the luminous intensity of each single-wavelength LED lamp can be independently controlled by the main control board of the multi-spectral projection system.

[0072] Please refer to the appendix Figure 4 , the near-infrared light source modulation module consists of an integrating sphere, a near-infrared spectrometer, a micro-irradiance meter, and a near-infrared LED lamp group. The near-infrared LED lamp group has a spectrum in the range of 700nm - 1000nm, each LED lamp is a single wavelength, the central wavelength interval is 10nm, and the luminous intensity of each single-wavelength LED lamp can be independently controlled by the main control board of the multi-spectral projection system.

[0073] The above describes the present invention by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited by the above methods. As long as such non-substantial improvements are made using the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A method for dynamically simulating a low-light night vision target with variable distance and variable spectrum, characterized in that, it includes the following steps: S1: The central control computer sends the spectral information of the target to be simulated to the multi-spectral projection system, Information 1: the spectral characteristic curve and illuminance value of the visible light source modulation module, Information 2: the spectral characteristic curve and illuminance value of the near-infrared light source modulation module; S2: The main control board of the multi-spectral projection system controls the brightness of each LED lamp in the visible light source modulation module. The visible light spectrometer and the low-light illuminometer respectively monitor the spectral characteristics and illuminance and feedback the monitoring data to the main control board. The main control board corrects the brightness of each LED lamp according to the monitoring data, so as to fit a light source that conforms to the visible light spectral characteristic curve given by the central control computer in S1. Finally, through the mixing and uniformizing of light in the integrating sphere, a uniform visible light source that meets the requirements is output from the light outlet of the integrating sphere; S3: The main control board of the multi-spectral projection system controls the brightness of each LED lamp in the near-infrared light source modulation module. The near-infrared spectrometer and the low-light irradiance meter respectively monitor the spectral characteristics and irradiance and feedback the monitoring data to the main control board. The main control board corrects the irradiance of each LED lamp according to the monitoring data, so as to fit a light source that conforms to the near-infrared spectral characteristic curve given by the central control computer in S1. Finally, through the mixing and uniformizing of light in the integrating sphere, a uniform near-infrared light source that meets the requirements is output from the light outlet of the integrating sphere; S4: The central control computer sends the size grayscale image of the target to be simulated to the multi-spectral projection system, First, solve the size information. For targets of the same size, the perceived size by the observer is different when the distance from the observer is different. The image size that the target to be simulated should generate on the visible light DMD module and the near-infrared DMD module of the multi-spectral projection system is calculated according to the following formula: Where: D 0 is the size of the target pattern on the DMD module, D 1 is the size of the target pattern in the real world, L 1 is the distance between the target pattern in the real world and the observer, f 1 is the focal length of the collimating objective lens β 1 is the projection magnification of the multispectral projection system; Furthermore, solve the grayscale information of visible light and near-infrared and send it to the multi-spectral projection system, Information 1: the image grayscale map of the R channel of visible light, the image grayscale map of the G channel, the grayscale map of the B channel image, Information 2: the image grayscale map of the near-infrared channel; S5: The main control board of the multi-spectral projection system controls the visible light DMD module according to the given grayscale map of the visible light R / G / B channels and outputs the image; S6: The main control board of the multi-spectral projection system controls the near-infrared DMD module according to the given grayscale map of the near-infrared channel and outputs the image; S7: After passing through their respective illumination lenses and TIR prisms, the visible light DMD module and the near-infrared DMD module are combined by a beam combining prism to fuse the visible light image and the near-infrared image, and the image is projected onto a wide-spectrum reflective screen through a projection lens, thereby simulating a low-light night vision target with a spectral range of 400nm to 1000nm; S8: The central control computer calculates the defocus distance of the wide-spectrum diffusive screen relative to the collimating objective lens according to the distance of the target to be simulated, and drives the electric displacement stage to move to the required distance through the motion controller, which is calculated by the following formula: Where: L 1 is the distance between the target pattern in the real world and the observer, L 2 is the distance between the wide-spectrum diffusive screen and the focal plane of the collimating objective lens, and f 2 is the focal length of the collimating objective lens; Through the above steps, the dynamic simulation of the distance, size, and spectral characteristics of the low-light target in the real world is realized.

2. An apparatus for dynamically simulating a low-light night vision target with variable distance and variable spectrum, characterized in that: It includes a collimating objective lens, a multispectral projection system, an electric displacement stage, a motion controller, a wide-spectrum diffuse reflection screen, a central control computer, an optical platform, and a support base; The collimating objective lens is used for collimating low-light targets and simulating distances. The multispectral projection system is used to project dynamic low-light patterns with variable spectra. The wide-spectrum diffuse reflection screen is used to receive the low-light patterns projected by the multispectral projection system. The electric displacement stage moves back and forth along the optical axis of the collimating system, and is used to change the distances between the multispectral projection system and the wide-spectrum reflection screen and the collimating system. The motion controller is used to calculate and control the forward and backward movement distances and speeds of the electric displacement stage. The central control computer is used to control the motion controller and the multispectral projection system; The multispectral projection system consists of a main control board, a visible light source modulation module, a visible light illumination lens, a visible light TIR prism, a visible light DMD module, a near-infrared light source modulation module, a near-infrared illumination lens, a near-infrared TIR prism, a near-infrared DMD module, a beam-combining prism, and a projection lens. After the visible light DMD module and the near-infrared DMD module pass through their respective illumination lenses and TIR prisms, they are combined by the beam-combining prism to fuse the visible light image and the near-infrared image, and the image is projected onto the wide-spectrum diffuse reflection screen through the projection lens, thereby simulating a low-light night vision target with a spectral range of 400nm to 1000nm.

3. An apparatus for dynamically simulating a low-light night vision target with variable distance and variable spectrum according to claim 2, characterized in that: The visible light source modulation module consists of an integrating sphere, a visible light spectrometer, a micro-illuminance meter, and a visible light LED lamp group. The visible light LED lamp group has a spectrum in the range of 400nm to 700nm, and each LED lamp is a single wavelength, with a central wavelength interval of 10nm. The luminous intensity of each single-wavelength LED lamp can be individually controlled by the main control board of the multispectral projection system.

4. An apparatus for dynamically simulating a low-light night vision target with variable distance and variable spectrum according to claim 3, characterized in that: The near-infrared light source modulation module consists of an integrating sphere, a near-infrared spectrometer, a micro-irradiance meter, and a near-infrared LED lamp group. The spectrum of the near-infrared LED lamp group is in the range of 700nm to 1000nm, and each LED lamp is a single wavelength, with a central wavelength interval of 10nm. The luminous intensity of each single-wavelength LED lamp can be individually controlled by the main control board of the multispectral projection system.

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