A device and method for realizing multi-aperture coaxial based on atmospheric illumination backscattering light

Abstract

The application discloses a device and method for realizing multi-aperture coaxial based on atmospheric illumination backscattering light, which comprises a laser, a transmitting aperture, a detecting aperture and an imaging system; the pulsed laser emitted by the laser enters the transmitting aperture and then passes through a single-aperture telescope, and is shot into the atmosphere after the transmitting direction is adjusted by a light beam deflection scanning device; the detecting aperture is responsible for receiving atmospheric illumination backscattering light at a specified distance and target reflection light reflected from a target; the atmospheric illumination backscattering light from the detecting aperture enters the imaging system and is converged into an imaging camera by a converging lens, and a focused light spot is formed on a target surface of the imaging camera; according to the position of the focused light spot of the imaging camera, a multi-aperture telescope optical axis fine adjustment device of the detecting aperture is adjusted by an algorithm until all the focused light spots are coincided, and the coaxial of the detecting aperture is realized. The technical scheme of the application has the advantages of simple structure, low cost and easy realization.

Description

Technical Field

[0001] This invention belongs to the field of applied optics in optical engineering, and specifically relates to a device and method for achieving multi-aperture coaxiality based on atmospheric illumination backscattered light. Background Technology

[0002] Multi-aperture synthesis technology can effectively improve laser emission or reception power and is widely used in fields such as photoelectric detection, lidar, and space laser communication. A multi-aperture synthesis scanning detection system consists of optical multi-apertures and beam deflectors. Optical multi-apertures, through multi-aperture synthesis detection, can effectively improve the system's imaging resolution and detection range. Simultaneously, the multi-apertures, through the beam deflector, enable large-angle, rapid scanning detection. During large-angle scanning in a multi-aperture synthesis detection system, the optical axes of all emission and detection apertures change rapidly. Due to manufacturing, assembly, and control errors between the sub-apertures, optical axis errors between apertures are unavoidable during scanning. Ultimately, this leads to non-confocal imaging of the sub-apertures in the multi-aperture synthesis scanning detection system, preventing real-time image synthesis and thus limiting the system's imaging resolution and detection range. Summary of the Invention

[0003] Therefore, the technical problem to be solved by this invention is: to create a large-angle beacon light to calibrate the optical axes of each sub-aperture in a multi-aperture synthetic scanning detection system in real time, overcoming the problem of inconsistency between optical axes among multiple apertures during large-angle scanning of the multi-aperture synthetic scanning detection system. Without adding external components, the invention utilizes an active illumination source with a pulsed emission aperture and collects atmospheric backscattered light from a specified distance during the transmission of the pulsed beam to the target as a beacon light to adjust the optical axis of the detection aperture, thereby achieving active coaxial detection.

[0004] This invention provides a device and method for achieving multi-aperture coaxiality based on atmospheric illumination backscattered light, specifically:

[0005] A device for achieving multi-aperture coaxiality based on atmospheric backscattered light includes a laser, an emission aperture, a detection aperture, and an imaging system. The pulsed laser is emitted from the laser, passes through the emission aperture into the atmosphere, then returns to the detection aperture, and finally enters the imaging system.

[0006] The emission aperture consists of a single-aperture telescope and a beam deflection and scanning device. After the pulsed laser emitted by the laser enters the emission aperture, it passes through the single-aperture telescope. The beam deflection and scanning device adjusts the emission direction before it enters the atmosphere, forming a beacon at a specified distance. It then continues to propagate until it illuminates the target.

[0007] The detection aperture consists of a multi-aperture telescope and a beam deflection scanning device. It is responsible for receiving atmospheric illumination backscattered light at a specified distance and receiving target reflected light reflected back from the target. The detection direction is changed by the beam deflection scanning device to capture atmospheric illumination backscattered light and target reflected light. After passing through the beam deflection scanning device, the atmospheric illumination backscattered light and target reflected light enter the imaging system through the multi-aperture telescope.

[0008] The imaging system consists of a converging lens and an imaging camera. After the atmospheric illumination backscattered light from the detector aperture enters the imaging system, it is converged by the converging lens and enters the imaging camera, forming a focused spot on the target surface of the imaging camera. Based on the position of the focused spot, the algorithm adjusts the fine adjustment device of the multi-aperture telescope of the detector aperture until all focused spots coincide, at which point the optical axes of the emission aperture and the detector aperture are coaxial. Subsequently, the target reflected light enters the imaging camera and forms a focused spot on the target surface of the imaging camera. After analyzing and calculating the focused spot, the target information is obtained, completing the multi-aperture coaxial detection of the target.

[0009] A method for achieving multi-aperture coaxial alignment based on atmospheric illumination backscattered light, the method comprising the following steps:

[0010] The laser emits a pulsed laser to illuminate the target, forming a beacon at a specified distance, and then continues to propagate until it illuminates the target. The detection aperture receives the atmospheric illumination backscattered light at the specified distance.

[0011] After the atmospheric illumination backscattered light from the probe aperture enters the imaging camera through the converging lens, the atmospheric illumination backscattered light forms a focused spot on the target surface of the imaging camera.

[0012] Based on the position of the focused spot of the imaging camera, the algorithm adjusts the fine adjustment device of the optical axis of the multi-aperture telescope until all focused spots coincide, at which point the optical axes of the emission aperture and the detection aperture are coaxial.

[0013] Subsequently, the reflected light from the target enters the imaging camera and forms a focused spot on the target surface of the imaging camera. After analyzing and calculating the focused spot, the target information is obtained, and the multi-aperture coaxial detection of the target is completed.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] (1) This invention cleverly utilizes the atmospheric backscattered light during the transmission of the existing pulsed illumination beam to achieve coaxiality of the emission aperture and the detection aperture. It can realize multi-aperture optical axis error detection without adding equipment, and has the advantages of simple structure, cost saving and easy implementation.

[0016] (2) This invention utilizes the atmospheric backscattered light during the transmission of the existing pulsed illumination beam to calibrate the optical axis error of the multi-aperture system, and uses the time difference between backscattering and target echo to achieve integrated optical axis calibration and target detection.

[0017] (3) The present invention can change the exposure time of the optical axis camera according to the actual target distance, and freely control the beacon light generation distance and sampling thickness. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the method and apparatus for achieving multi-aperture coaxiality based on atmospheric illumination backscattered light in this invention, which involves emitting illumination pulse laser and receiving target reflected light and atmospheric illumination backscattered light. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this should not be construed as limiting the scope of protection of the present invention.

[0020] Figure 1 This is a schematic diagram illustrating the process of emitting pulsed illumination laser light and receiving target reflected light and atmospheric illumination backscattered light in a method and apparatus for achieving multi-aperture coaxiality based on atmospheric illumination backscattered light according to the present invention.

[0021] like Figure 1 As shown, an embodiment of the present invention discloses a device for achieving multi-aperture coaxiality based on atmospheric illumination backscattered light, comprising a laser, an emitting aperture, a detecting aperture, and an imaging system. A pulsed laser is emitted from the laser, passes through the emitting aperture into the atmosphere, then returns to the detecting aperture, and finally enters the imaging system. After the laser emits a pulsed laser, the atmospheric illumination backscattered light reaches the detecting aperture after a time interval of twice the beacon distance divided by the speed of light, entering the imaging system to assist in coaxial adjustment; after the laser emits a pulsed laser, the target reflected light reaches the detecting aperture after a time interval of twice the target distance divided by the speed of light, entering the imaging system to provide target information; then the laser emits the next pulsed laser beam, and the system continues to receive atmospheric illumination backscattered light and target reflected light.

[0022] The emission aperture consists of a single-aperture telescope and a beam deflection scanning device. After the pulsed laser emitted by the laser enters the emission aperture, it passes through the single-aperture telescope. The beam deflection scanning device adjusts the emission direction before it enters the atmosphere, forming a beacon at a specified distance. It then continues to propagate until it illuminates the target.

[0023] The detection aperture consists of a multi-aperture telescope and a beam deflection scanning device. It receives atmospheric illumination backscattered light from a specified distance and target reflected light. The beam deflection scanning device changes the detection direction to capture both the atmospheric illumination backscattered light and the target reflected light. Atmospheric illumination backscattered light arrives at the detection aperture earlier than the target reflected light. This backscattered light enters the detection aperture and then the imaging system, providing coaxial adjustment information. The imaging camera reflects the optical axis errors of each aperture, and the multi-aperture telescope's fine-tuning device achieves coaxiality between the emission and detection apertures. The target reflected light then arrives at the detection aperture, and the imaging system receives it, completing the target detection. The atmospheric illumination backscattered light and target reflected light, after passing through the beam deflection scanning device, enter the imaging system via the multi-aperture telescope.

[0024] The beam deflection and scanning devices in the emission and detection apertures can be prisms, fast reflectors, or liquid crystal phased arrays, etc., to control the emission and reception directions of the laser.

[0025] In addition to using beam deflection scanning devices for coarse optical axis adjustment, single-aperture and multi-aperture telescopes also employ fast-reflection mirrors, MEMS, and other optical axis fine adjustment devices for fine optical axis adjustment. These two components form a coarse-fine composite structure, enabling large-angle two-dimensional fine motion of the optical axis in the vertical plane and precisely controlling the optical axis direction of the emission aperture and the detection aperture.

[0026] The imaging system consists of a converging lens and an imaging camera. Atmospheric illumination backscattered light from the detector aperture enters the imaging system and is converged by the converging lens into the imaging camera. The atmospheric illumination backscattered light provides the optical axis direction of the detector aperture. The gating time of the imaging camera is set according to the arrival times of the atmospheric illumination backscattered light and the target reflected light. After the atmospheric illumination backscattered light from the detector aperture enters the imaging camera through the converging lens, it forms a focused spot on the target surface of the imaging camera. Based on the position of the focused spot, the multi-aperture telescope's optical axis fine adjustment device is adjusted by an algorithm until all focused spots coincide, at which point the emission aperture and the detector aperture's optical axes are coaxial. Subsequently, the target reflected light enters the imaging camera and forms a focused spot on the target surface of the imaging camera. Analyzing and calculating the focused spot yields target information, completing the multi-aperture coaxial detection of the target. Those skilled in the art can choose any algorithm to analyze and calculate the focused spot; the coaxial detection process is also well-known to those skilled in the art.

[0027] According to an embodiment of the present invention, a method for achieving multi-aperture coaxiality based on atmospheric illumination backscattered light is provided, the method comprising the following steps:

[0028] The laser emits a pulsed laser to illuminate the target, forming a beacon at a specified distance, and then continues to propagate until it illuminates the target. The detection aperture receives the atmospheric illumination backscattered light at the specified distance.

[0029] The atmospheric illumination backscattered light from the probe aperture enters the imaging camera through a converging lens and forms a focused spot on the target surface;

[0030] Based on the position of the focused spot of the imaging camera, the algorithm adjusts the fine adjustment device of the optical axis of the multi-aperture telescope until all focused spots coincide, at which point the optical axes of the emission aperture and the detection aperture are coaxial.

[0031] Subsequently, the reflected light from the target enters the imaging camera and forms a focused spot on the target surface of the imaging camera. After analyzing and calculating the focused spot, the target information is obtained, and the multi-aperture coaxial detection of the target is completed.

[0032] In one embodiment, the emitted laser is pulsed light.

[0033] In one embodiment, during a large-angle scan, the imaging system can first receive atmospheric illumination backscattered light from a specified distance, and then receive target reflected light from multiple detector apertures, by controlling the gating time. Receiving the atmospheric illumination backscattered light allows for the acquisition of the optical axis distribution of the multiple detector apertures. This optical axis distribution is used to control the deflection of the optical axis direction of each detector aperture, forming multiple coaxial points, thereby achieving coaxiality of the multiple detector apertures, as described in the above method steps. Controlling the gating time to receive the target reflected light from the multiple detector apertures enables the synthetic detection of the target.

[0034] Based on the above description, by controlling the gating time, the detection aperture can first receive atmospheric illumination backscattered light to complete coaxial adjustment, and then receive target reflected light to achieve multi-aperture coaxial detection.

[0035] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. An apparatus for realizing multi-aperture co-axial based on atmospheric illumination backscattered light, characterized in that, The pulse laser is emitted from the laser, passes through the transmitting aperture, enters the atmosphere, and then returns to the detecting aperture, and finally enters the imaging system; The transmitting aperture is composed of a single-aperture telescope and a beam deflection scanning device. The pulse laser emitted by the laser enters the transmitting aperture, passes through the single-aperture telescope, and is adjusted by the beam deflection scanning device to change the direction of emission, and then enters the atmosphere. The pulse laser forms a beacon at a specified distance, and then continues to propagate until it irradiates on the target. The detecting aperture is composed of a multi-aperture telescope and a beam deflection scanning device. The detecting aperture is responsible for receiving the atmospheric illumination backscattering light at the specified distance and the target reflection light reflected from the target. The beam deflection scanning device changes the detection direction to capture the atmospheric illumination backscattering light and the target reflection light. After passing through the beam deflection scanning device, the atmospheric illumination backscattering light and the target reflection light enter the imaging system through the multi-aperture telescope. The imaging system is composed of a converging lens and an imaging camera. The atmospheric illumination backscattering light from the detecting aperture enters the imaging system and is converged by the converging lens into the imaging camera. The focused spots are formed on the target surface of the imaging camera. According to the position of the focused spots of the imaging camera, the multi-aperture telescope optical axis fine adjustment device of the detecting aperture is adjusted by the algorithm until all the focused spots coincide. At this time, the optical axes of the transmitting aperture and the detecting aperture are coaxial. Then, the target reflection light enters the imaging camera and forms focused spots on the target surface of the imaging camera. After analyzing and calculating the focused spots, the target information is obtained, and the multi-aperture coaxial detection of the target is completed. The optical axis fine adjustment device includes a fast mirror, a MEMS, a beam deflection scanning device, and an optical axis fine adjustment device. The coarse-fine composite structure is formed by the beam deflection scanning device and the optical axis fine adjustment device. The optical axis can move finely in the vertical plane in a large angle two-dimensional manner, and the direction of the optical axis of the transmitting aperture and the detecting aperture can be accurately controlled.

2. The device for realizing multi-aperture coaxial based on atmospheric illumination backscattering light according to claim 1, characterized in that, After the laser emits the pulse laser, the atmospheric illumination backscattering light reaches the detecting aperture after a time of twice the beacon distance divided by the speed of light.

3. The device for realizing multi-aperture coaxial based on atmospheric illumination backscattering light according to claim 1, characterized in that, After the laser emits the pulse laser, the target reflection light reaches the detecting aperture after a time of twice the target distance divided by the speed of light.

4. The device for realizing multi-aperture coaxial based on atmospheric illumination backscattering light according to claim 1, characterized in that, The beam deflection scanning devices in the transmitting aperture and the detecting aperture are selected from prisms, fast mirrors, or liquid crystal phased arrays to control the direction of emission and reception of the laser.

5. A method for achieving multi-aperture co-axiality based on atmospheric backscattered light, executed by the device for achieving multi-aperture co-axiality based on atmospheric backscattered light according to any one of claims 1-4, characterized in that, The method comprises the following steps: The pulse laser illuminates the target, forms a beacon at a specified distance, and then continues to propagate until it irradiates on the target. The detecting aperture receives the atmospheric illumination backscattering light at the specified distance and the target reflection light reflected from the target. The atmospheric illumination backscattering light of the detecting aperture enters the imaging camera through the converging lens and forms focused spots on the target surface of the imaging camera. According to the position of the focused spots of the imaging camera, the multi-aperture telescope optical axis fine adjustment device of the detecting aperture is adjusted by the algorithm until all the focused spots coincide. At this time, the optical axes of the transmitting aperture and the detecting aperture are coaxial. The optical axis fine adjustment device includes a fast mirror, a MEMS, a beam deflection scanning device, and an optical axis fine adjustment device. The coarse-fine composite structure is formed by the beam deflection scanning device and the optical axis fine adjustment device. The optical axis can move finely in the vertical plane in a large angle two-dimensional manner, and the direction of the optical axis of the transmitting aperture and the detecting aperture can be accurately controlled. Subsequently, the target reflected light enters the imaging camera and forms a focused spot on the target surface of the imaging camera. After analyzing and calculating the focused spot, target information is obtained, and the multi-aperture coaxial detection of the target is completed.

6. The method of claim 5, wherein the method is characterized in that, During the large-angle scanning process, the imaging system first receives the atmospheric illumination backscattering light at a specified distance and then receives the target reflected light by controlling the gating time.

7. The method of claim 5, wherein, Further comprising: The atmospheric illumination backscattering light is received, the optical axis distribution of the multi-path detection aperture is obtained, the deflection of the optical axis direction of each detection aperture is controlled through the optical axis distribution, and the multi-path detection aperture is coaxial.

8. The method of claim 5, wherein the method is implemented by a plurality of apertures in a coaxial manner based on atmospheric illumination backscattered light. After the pulsed laser is emitted, the atmospheric illumination backscattering light reaches the detection aperture after a time of twice the beacon distance divided by the speed of light.

9. The method of claim 5, wherein, After the pulsed laser is emitted, the target reflected light reaches the detection aperture after a time of twice the target distance divided by the speed of light.

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