Laser incidence direction detection method and system

Abstract

The invention provides a laser incidence direction detection method and system, and relates to the field of laser detection. The laser incidence direction detection system comprises an array optical fiber coupler, an array signal gating device and a photoelectric detector. Wherein the orientations of the optical fiber couplers in the array optical fiber couplers are different so as to receive the incident laser in the corresponding direction. And the photoelectric detector realizes multichannel parallel connection with the array optical fiber coupler through the array signal gating device. When the laser incident direction detection system works, sequential control is carried out on the array signal gating device, only partial channels are conducted at any time, and then the direction of incident laser is determined according to the corresponding sequential time when the photoelectric detector detects laser signals. The number of used photoelectric detectors can be reduced during large-field-of-view detection, and the cost is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of laser detection, and particularly relates to a method and system for detecting the incident direction of laser light. Background Art

[0002] In applications such as industrial manufacturing and aerospace, it is often necessary to determine the direction of a laser signal for activities such as communication, measurement, and docking. The determination of the direction of a laser signal requires laser incident direction detection technology.

[0003] Currently, the commonly used laser incident direction detection technologies mainly include approximate direction detection technology and high-precision direction detection technology.

[0004] Approximate direction detection technology generally requires multi-channel point or line array photodetectors in cooperation with a mask to achieve a large field of view and a direction resolution accuracy of about 1°. High-precision direction detection technology generally requires a combination of multi-channel area array photodetectors and imaging optical systems to achieve a large field of view and a direction resolution accuracy of about 1 mrad. Approximate direction detection technology usually has a relatively lower cost and is used in scenarios with low accuracy requirements.

[0005] Currently, regardless of which direction detection technology, to obtain large-field-of-view detection, multiple photodetectors are required, and high-performance photodetectors are usually expensive. Therefore, the cost of large-field-of-view laser direction detection is greatly affected by the cost of photodetectors. Summary of the Invention

[0006] To solve the above technical problems, the present invention proposes a method and system for detecting the incident direction of laser light.

[0007] In a first aspect of the present invention, a laser incident direction detection system is disclosed. The laser incident direction detection system includes an array fiber coupler, an array signal selector, and a photodetector; wherein,

[0008] The directions of each fiber coupler in the array fiber coupler are all different to receive incident laser light from corresponding directions;

[0009] The photodetector is connected to the array fiber coupler in a multi-channel parallel manner through the array signal selector;

[0010] When the laser incident direction detection system operates, by performing timing control on the array signal selector, only some channels are conducted at any given time, and then the direction of the incident laser light is determined according to the timing corresponding to when the photodetector detects the laser signal.

[0011] The array signal selector includes a controller and multiple optical fibers with optical fiber attenuators; wherein,

[0012] The number of optical fibers is the same as the number of fiber couplers;

[0013] The input port of each optical fiber is connected to an optical fiber coupler; the optical fiber coupler is used to couple the incident laser in the corresponding direction into the corresponding optical fiber.

[0014] The output ports of multiple optical fibers are all coupled to the photosensitive surface of the photodetector.

[0015] The controller controls the attenuation rate of the optical fiber attenuator according to the timing sequence to achieve that only some channels are turned on at any time.

[0016] The controller controls the conduction of channels row by row or column by column to achieve rough detection of the incident direction of the laser; if the photodetector detects a laser signal when the channels in the nth row or column are turned on, each channel in the nth row or column is sequentially turned on through the controller until the photodetector responds. At this time, the direction pointed by the turned-on channels is the incident direction of the laser.

[0017] The array signal selector and a photodetector are integrated on a circuit board; the array optical fiber coupler is fixedly arranged on a flat or curved panel and arranged in an array shape.

[0018] The second aspect of the present invention discloses a method for detecting the incident direction of a laser. The method is implemented by the laser incident direction detection system described in any one of the above. The method includes:

[0019] By performing timing control on the array signal selector, only some channels are turned on at any time, and then according to the timing corresponding to the laser signal detected by the photodetector, the incident direction of the incident laser is determined.

[0020] The step array signal selector includes a controller and multiple optical fibers with optical fiber attenuators; wherein,

[0021] The number of optical fibers is the same as the number of optical fiber couplers.

[0022] The input port of each optical fiber is connected to an optical fiber coupler; the optical fiber coupler is used to couple the incident laser in the corresponding direction into the corresponding optical fiber.

[0023] The output ports of multiple optical fibers are all coupled to the photosensitive surface of the photodetector.

[0024] The controller controls the attenuation rate of the optical fiber attenuator according to the timing sequence to achieve that only some channels are turned on at any time.

[0025] The controller controls the conduction of the channels row by row or column by column to achieve a rough detection of the laser incident direction. If a laser signal is detected by the photodetector when the channels in the nth row or column are conducting, each channel in the nth row or column is sequentially conducted through the controller until the photodetector responds. At this time, the direction indicated by the conducting channels is the laser incident direction.

[0026] The third aspect of the present invention discloses a laser incident direction detection device, including a housing and a laser incident direction detection system disposed on the housing.

[0027] The laser incident direction detection system includes an array fiber coupler, an array signal selector, and a photodetector. Among them,

[0028] The directions of each fiber coupler in the array fiber coupler are all different to receive the incident laser from the corresponding direction.

[0029] The photodetector is connected to the array fiber coupler in a multi-channel parallel manner through the array signal selector.

[0030] When the laser incident direction detection system works, by performing timing control on the array signal selector, only some channels are conducted at any time. Then, according to the timing corresponding to when the photodetector detects the laser signal, the direction of the incident laser is determined.

[0031] In summary, the solution proposed by the present invention has the following technical effects: The laser incident direction detection system provided by the present invention can achieve the detection of the laser incident direction in the 360° direction only through one detector, which can reduce the number of photodetectors used during large-field detection and reduce costs. Description of the Drawings

[0032] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0033] Figure 1 It is the schematic diagram of the laser incident direction detection system according to the embodiment of the present invention;

[0034] Figure 2 It is the structural schematic diagram of the laser incident direction detection system according to the embodiment of the present invention;

[0035] Figure 3 It is the example diagram of the control timing according to the embodiment of the present invention. Detailed Embodiments

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are only a part rather than all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0037] The first aspect of the present invention discloses a laser incident direction detection system, which includes an array fiber coupler, an array signal gater, and a photodetector; wherein,

[0038] The directions of each fiber coupler in the array fiber coupler are different from each other to receive incident laser light from corresponding directions;

[0039] The photodetector is connected to the array fiber coupler through the array signal gater in a multi-channel parallel manner;

[0040] When the laser incident direction detection system works, by performing timing control on the array signal gater, only some channels are conducted at any moment, and then the direction of the incident laser is determined according to the timing corresponding to the laser signal detected by the photodetector.

[0041] It should be noted that the specific structures of the fiber coupler, the signal gater, and the photodetector are not specifically limited as long as the corresponding functions can be achieved. For example, in addition to including a fiber coupling lens that can couple spatial light into the fiber, the fiber coupler may also include a signal filter or a signal amplifier. Optionally, the signal filter or the signal amplifier may also be disposed in the photodetector.

[0042] Optionally, as Figure 1 shown, the array signal gater includes a controller and multiple optical fibers with fiber attenuators; wherein,

[0043] The number of optical fibers is the same as the number of fiber couplers; the input port of each optical fiber is connected to a fiber coupler; the fiber coupler is used to couple the incident laser light from the corresponding direction into the corresponding optical fiber; the output ports of the multiple optical fibers are all coupled to the photosensitive surface of the photodetector; the controller controls the attenuation rate of the fiber attenuator according to the timing to achieve that only some channels are conducted at any moment.

[0044] Couple the photosensitive surface of the photodetector with the port after combining multiple optical fibers. Each of the multiple optical fibers is equipped with an electrically tunable optical attenuator, and the other port of each optical fiber is connected to an optical fiber coupling lens, which can couple spatial light into the optical fiber. Each optical fiber coupling lens points in a different direction to receive laser signals from various directions. Since only 1 photodetector is used, if all the optical fibers are turned on simultaneously, it is impossible to determine the direction from which the laser signal comes. Therefore, it is necessary to control the attenuation rate of each optical fiber through timing to ensure that only a few or a single optical fiber has the ability to transmit light at any given moment. The control of the optical fiber attenuation rate can be achieved through electrical signals. When the optical fiber in a certain direction is turned on and the received laser signal causes the photodetector to produce a high-level output, the direction of the laser can be determined. The more the number of optical fibers, the larger the covered field of view and the higher the direction resolution accuracy.

[0045] Optionally, the array signal selector and a photodetector are integrated on a circuit board; the array optical fiber coupler is fixedly arranged on a flat or curved panel and arranged in an array shape. Please refer to Figure 2 , the system includes a photodetection and optical fiber attenuation control circuit board and multiple optical fiber coupling lenses. The photodetection and optical fiber attenuation control circuit board includes a photodetector, an FPGA, and multiple optical fiber attenuators.

[0046] Optionally, in order to improve the detection efficiency while ensuring the detection accuracy, the controller controls the conduction of the channels row by row or column by column to achieve a rough detection of the laser incident direction; if the photodetector detects a laser signal when the channels in the nth row or column are turned on, then the controller makes each channel in the nth row or column turn on in sequence until the photodetector responds. At this time, the direction pointed by the turned-on channel is the laser incident direction.

[0047] For example, the FPGA controls the attenuation rate of the optical fiber attenuator according to the timing to ensure that only a few or a single optical fiber is turned on at any given moment. The control timing is as Figure 3 shown. The optical fiber coupling lenses can be fixed on a flat or curved panel and arranged in an array shape, and each optical fiber coupling lens points in a different direction. The FPGA first controls the attenuation rate of the optical fiber attenuators in the first column to become lower, and the attenuation rates of the other optical fiber attenuators remain at a high level. If the photodetector does not respond within the dwell time, then it controls the attenuation rate of the optical fiber attenuators in the first column to become higher and controls the attenuation rate of the optical fiber attenuators in the second column to become lower, and so on. This is the coarse scan. If the photodetector responds during the time when the attenuation rate of the optical fiber attenuators in the nth column becomes lower, then it enters the fine scan. At this time, the FPGA pulls down the attenuation rate of the optical fiber attenuators in this column one by one in a certain direction until the photodetector responds. At this time, the direction pointed by the turned-on optical fiber is the direction of the laser.

[0048] A second aspect of the present invention discloses a method for detecting the laser incident direction, which is implemented by the laser incident direction detection system described in any one of the above. The method includes:

[0049] By performing timing control on the array signal gater, only part of the channels are conducted at any time, and then according to the timing corresponding to the laser signal detected by the photodetector, the direction of the incident laser is determined.

[0050] The step array signal gater includes a controller and multiple optical fibers with fiber optic attenuators; where

[0051] The number of optical fibers is the same as the number of fiber optic couplers;

[0052] The input port of each optical fiber is connected to a fiber optic coupler; the fiber optic coupler is used to couple the incident laser in the corresponding direction into the corresponding optical fiber;

[0053] The output ports of the multiple optical fibers are all coupled to the photosensitive surface of the photodetector;

[0054] The controller controls the attenuation rate of the fiber optic attenuator according to the timing to achieve that only part of the channels are conducted at any time.

[0055] The controller controls the conduction of the channels in sequence by rows or columns to achieve a rough detection of the laser incident direction; if the photodetector detects a laser signal when the channels in the nth row or column are conducted, then each channel in the nth row or column is sequentially conducted through the controller until the photodetector responds. At this time, the direction pointed to by the conducted channels is the direction of the incident laser.

[0056] A third aspect of the present invention discloses a laser incident direction detection device, including a housing and a laser incident direction detection system disposed on the housing;

[0057] The laser incident direction detection system includes an array fiber optic coupler, an array signal gater, and a photodetector; where

[0058] The directions of each fiber optic coupler in the array fiber optic coupler are all different to receive the incident laser in the corresponding direction;

[0059] The photodetector is connected to the array fiber optic coupler through the array signal gater in a multi-channel parallel manner;

[0060] When the laser incident direction detection system works, by performing timing control on the array signal gater, only part of the channels are conducted at any time, and then according to the timing corresponding to the laser signal detected by the photodetector, the direction of the incident laser is determined.

[0061] In summary, the solution proposed by the present invention has the following technical effects: The laser incident direction detection system provided by the present invention can achieve the detection of the incident direction of the laser in the 360° direction only through one detector, which can reduce the number of photodetectors used during large field-of-view detection and lower the cost.

[0062] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that the technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features can be equivalently replaced, and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A laser incident direction detection system, characterized in that: The laser incident direction detection system includes an array fiber coupler, an array signal gate and a photoelectric detector; wherein, Each optical fiber coupler in the array optical fiber coupler has a different orientation so as to receive incident laser light from a corresponding direction; The photoelectric detector is connected in parallel with the array optical fiber coupler through an array signal gate; When the laser incident direction detection system is working, the array signal selector is controlled in time sequence so that only some channels are turned on at any time, and then the direction of the incident laser is determined according to the corresponding timing when the photoelectric detector detects the laser signal.

2. The laser incident direction detection system according to claim 1, characterized in that: The array signal gate includes a controller and a plurality of optical fibers with optical fiber attenuators; wherein, The number of optical fibers is the same as the number of fiber couplers; The input port of each optical fiber is connected to a fiber coupler; the fiber coupler is used to couple the incident laser of the corresponding direction into the corresponding optical fiber; The output ports of the multiple optical fibers are all coupled to the photosensitive surface of the photodetector; The controller controls the attenuation rate of the optical fiber attenuator according to the timing so that only part of the channels are turned on at any time.

3. The laser incident direction detection system according to claim 2, characterized in that: The controller controls the conduction of the channels in sequence according to rows or columns to achieve rough detection of the incident direction of the laser; if the photodetector detects a laser signal when the channel in the nth row or column is turned on, the controller turns on each channel in the nth row or column in sequence until the photodetector responds, at which point the direction indicated by the turned-on channel is the incident direction of the laser.

4. The laser incident direction detection system according to any one of claims 1 to 3, characterized in that: An array signal selector and a photoelectric detector are integrated on a circuit board; an array optical fiber coupler is fixedly arranged on a flat or curved panel and arranged in an array shape.

5. A method for detecting a laser incident direction, characterized in that: The method is implemented by the laser incident direction detection system according to any one of claims 1 to 4, and the method comprises: By controlling the timing of the array signal selector, only some channels can be turned on at any time, and then the direction of the incident laser can be determined according to the corresponding timing when the photodetector detects the laser signal.

6. The method according to claim 5, characterized in that The step array signal selector includes a controller and a plurality of optical fibers with optical fiber attenuators; wherein, The number of optical fibers is the same as the number of fiber couplers; The input port of each optical fiber is connected to a fiber coupler; the fiber coupler is used to couple the incident laser of the corresponding direction into the corresponding optical fiber; The output ports of the multiple optical fibers are all coupled to the photosensitive surface of the photodetector; The controller controls the attenuation rate of the optical fiber attenuator according to the timing so that only part of the channels are turned on at any time.

7. The method according to claim 6, characterized in that The controller controls the conduction of the channels in sequence according to rows or columns to achieve rough detection of the incident direction of the laser; if the photodetector detects a laser signal when the channel in the nth row or column is turned on, the controller turns on each channel in the nth row or column in sequence until the photodetector responds, at which point the direction indicated by the turned-on channel is the incident direction of the laser.

8. A laser incident direction detection device, characterized in that: It includes a shell and a laser incident direction detection system arranged on the shell; The laser incident direction detection system includes an array fiber coupler, an array signal gate and a photoelectric detector; wherein, Each optical fiber coupler in the array optical fiber coupler has a different orientation so as to receive incident laser light from a corresponding direction; The photoelectric detector is connected in parallel with the array optical fiber coupler through an array signal gate; When the laser incident direction detection system is working, the array signal selector is controlled in time sequence so that only some channels are turned on at any time, and then the direction of the incident laser is determined according to the corresponding timing when the photoelectric detector detects the laser signal.

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