A large-span photoelectric turntable optical axis calibration device

Abstract

This invention relates to the field of turntable optical axis calibration technology, specifically to a large-span photoelectric turntable optical axis calibration device. The device includes a light source, a collimator, an autocollimator, an electrically adjustable beam splitter group, an electrically adjustable reflector, and a first displacement slide. The electrically adjustable beam splitter group consists of multiple cascaded electrically adjustable beam splitters, with one fewer than the total number of sensors to be calibrated, thereby sequentially splitting a beam of parallel light and distributing it to N sensors. Two calibration mirrors enable the autocollimator to perform high-precision angle calibration on each level of the electrically adjustable beam splitter and electrically adjustable reflector. This invention, through modular cascaded beam splitting and a unique calibration design, achieves high-precision, simultaneous calibration of the optical axes of any number of sensors using only a conventional aperture collimator, overcoming the shortcomings of traditional methods such as high cost, poor scalability, and difficult calibration.

Description

Technical Field

[0001] This utility model relates to the field of turntable optical axis calibration technology, specifically to a large-span photoelectric turntable optical axis calibration device. Background Technology

[0002] With the rapid development of low-altitude economy and other fields, photoelectric turntable equipment has been widely used. To meet the needs of diversified functions and high performance, the number and size of photoelectric sensors mounted on the turntable have increased, resulting in a larger turntable span. At the same time, the accuracy requirements for the consistency of the optical axes of multiple sensors are also becoming increasingly higher.

[0003] Traditional methods for calibrating the optical axis of a large-span turntable typically require collimators with large apertures, but these collimators are difficult and expensive to manufacture. Another method involves using dual collimators and dual theodolites for calibration, but this method suffers from low calibration accuracy and significant errors. Therefore, there is an urgent need for a device that can achieve consistent optical axis calibration of multiple sensors on a large-span photoelectric turntable with low cost and high accuracy. Utility Model Content

[0004] Therefore, the technical problem to be solved by this utility model is to overcome the defects in the prior art, thereby providing a large-span photoelectric turntable optical axis calibration device.

[0005] A large-span photoelectric turntable optical axis calibration device includes: light source; A collimator is used to convert light emitted from a light source into a parallel beam. Autocollimator; An electrically adjustable beam splitter assembly is formed by cascading at least one electrically adjustable beam splitter along the optical path; the first electrically adjustable beam splitter is disposed on the outgoing optical path of the collimator, and each electrically adjustable beam splitter is used to split the incident beam into reflected light reflected to a sensor to be calibrated and transmitted light transmitted to the next level optical element. An electrically adjustable reflector is placed in the transmission light path of the last electrically adjustable beam splitter to reflect the incident light beam to a sensor to be calibrated. The first displacement slide is used to support and drive the electrically tunable beam splitter group and the electrically tunable reflector to move. A calibration mirror assembly, including at least one calibration mirror; The calibration displacement slide group includes at least one displacement slide for driving the calibration mirrors in the calibration mirror group to move into or out of the calibration optical path between the autocollimator and the corresponding electrically adjustable beam splitter or electrically adjustable reflector.

[0006] Furthermore, the electrically adjustable beam splitter assembly specifically includes a first electrically adjustable beam splitter and a second electrically adjustable beam splitter; the first electrically adjustable beam splitter is disposed on the outgoing light path of the collimator, the second electrically adjustable beam splitter is disposed on the transmitted light path of the first electrically adjustable beam splitter, and the electrically adjustable reflector is disposed on the transmitted light path of the second electrically adjustable beam splitter.

[0007] Furthermore, the first electrically adjustable beam splitter has a transmittance greater than its reflectance, and the second electrically adjustable beam splitter has a transmittance greater than its reflectance.

[0008] Furthermore, the calibration mirror assembly includes a first calibration mirror and a second calibration mirror; the calibration displacement slide assembly includes a second displacement slide for driving the first calibration mirror and a third displacement slide for driving the second calibration mirror.

[0009] Furthermore, all components of the large-span photoelectric turntable optical axis calibration device are mounted on a base, which is a six-degree-of-freedom piezoelectric platform.

[0010] Furthermore, the device also includes an environmental monitoring and compensation system, which includes at least one of a temperature sensor, a strain sensor, an infrared thermal imager, and a laser vibration meter mounted on the base, as well as a control unit; the control unit is used to control the six-degree-of-freedom piezoelectric platform, the electrically tunable beam splitter group, and the electrically tunable reflector to perform motion compensation based on sensor data.

[0011] Furthermore, the first displacement slide is a multi-axis slide, capable of independently driving the movement of any electrically adjustable beam splitter and the electrically adjustable reflector in the electrically adjustable beam splitter group.

[0012] The technical solution of this utility model has the following advantages: The large-span photoelectric turntable optical axis calibration device provided by this utility model uses a beam splitting module composed of N-1 electrically adjustable beam splitters cascaded together, in conjunction with an electrically adjustable reflector, to sequentially split the beam emitted by a single collimator. The reflected light path of each electrically adjustable beam splitter is precisely pointed to a sensor to be calibrated, while the electrically adjustable reflector provides the beam to the last sensor. This design utilizes conventional aperture collimators and the beam splitting principle to achieve consistent optical axis calibration for large spans and multiple sensors, fundamentally avoiding the use of expensive and difficult-to-manufacture large-aperture collimators, and significantly reducing system costs and manufacturing barriers.

[0013] The large-span optoelectronic turntable optical axis calibration device provided by this utility model has excellent scalability. The ability to calibrate the number of sensors in the device is directly determined by the number of electrically adjustable beam splitters. Users only need to add or remove electrically adjustable beam splitters in the optical path according to the actual number of sensors to flexibly and economically adapt to the calibration of different numbers of sensors, from two to dozens. This modular design makes the device highly versatile and solves the problem of traditional methods that require customized calibration equipment for different numbers of sensors.

[0014] The large-span optoelectronic turntable optical axis calibration device provided by this utility model combines an autocollimator and a calibration mirror that can precisely cut into the optical path. It can perform independent, perpendicular incident angle calibration for each electrically adjustable beam splitter and electrically adjustable reflector in the cascaded optical path, ensuring the accuracy of the angular reference height of all beam splitting and turning elements.

[0015] This invention employs a six-degree-of-freedom piezoelectric platform as its support base and can be optionally equipped with an environmental monitoring and dynamic compensation system integrating multiple sensors. This system can detect and actively compensate for optical path deviations caused by environmental factors such as long-span mechanical deformation and temperature changes in real time. This compensation mechanism significantly improves the system's stability and anti-interference capabilities in complex field environments. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the overall structure and calibration optical path of a specific embodiment of the present invention; Figure 2 This is a schematic diagram of the optical path during the calibration of the first electrically adjustable beam splitter. Figure 3 This is a schematic diagram of the optical path during the calibration of an electrically adjustable mirror.

[0018] Explanation of reference numerals in the attached figures: 1-Light source; 2-Collider; 3-Autocollimator; 4-First electrically adjustable beam splitter; 5-Second displacement slide; 6-First calibration mirror; 7-Third displacement slide; 8-Second calibration mirror; 9-Second electrically adjustable beam splitter; 10-Electrically adjustable reflector; 11-First displacement slide; 12-Large span turntable; 13-First sensor; 14-Second sensor; 15-Third sensor. Detailed Implementation

[0019] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0020] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0021] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0022] Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0023] The core of this invention lies in its cascaded beam-splitting architecture, which can be expanded to accommodate different numbers of sensors within a large-span turntable. This architecture consists of an electrically tunable beam-splitting mirror assembly, an electrically tunable reflector 10, and a matching calibration and drive system. The number of cascaded electrically tunable beam-splitting mirrors in the assembly is one less than the total number of sensors to be calibrated; that is, for N sensors, there are N-1 electrically tunable beam-splitting mirrors. Each electrically tunable beam-splitting mirror provides a calibration beam for one sensor and transfers the remaining light energy to the next stage. The electrically tunable reflector 10 receives the transmitted light from the final stage and provides a calibration beam for the last sensor. By increasing or decreasing the number of electrically tunable beam-splitting mirrors, this architecture can seamlessly adapt to calibration tasks with different numbers of sensors.

[0024] Example 1: like Figure 1As shown, in this embodiment, the total number of sensors N=3, so the electrically adjustable beam splitter group includes N-1=2 electrically adjustable beam splitters, namely the first electrically adjustable beam splitter 4 and the second electrically adjustable beam splitter 9.

[0025] The light emitted from light source 1 is converted into a parallel beam after passing through collimator 2. This beam first reaches the first electrically adjustable beam splitter 4 and is split into two paths: one path is reflected and directed towards the first sensor 13; the other path is transmitted and reaches the second electrically adjustable beam splitter 9. The second electrically adjustable beam splitter 9 splits the light again: its reflected light is directed towards the second sensor 14; its transmitted light reaches the electrically adjustable reflector 10, and after reflection, it is directed towards the third sensor 15. By adjusting the mechanical positions of the first sensor 13, the second sensor 14, and the third sensor 15, the crosshairs of each sensor are aligned with the center of the light spot, thus completing the calibration.

[0026] Before performing multi-sensor optical axis calibration, the positions and angles of each electrically adjustable beam splitter and electrically adjustable reflector in the entire device need to be calibrated. The calibration process is as follows: Each electrically adjustable beam splitter is calibrated sequentially according to the optical path order, such as... Figure 2 The first electrically adjustable beam splitter 4 is calibrated. The first calibration mirror 6 is inserted into the optical path through the second displacement slide 5. The autocollimator 3 is turned on. The light emitted by the autocollimator 3 is reflected by the first electrically adjustable beam splitter 4 to the first calibration mirror 6. The mechanical position of the first electrically adjustable beam splitter 4 is adjusted for coarse angle adjustment. Then, the angle is finely adjusted using the fine adjustment system of the first electrically adjustable beam splitter 4 until the autocollimated image is centered. The calibration of the first electrically adjustable beam splitter 4 is then completed. When calibrating the second electrically adjustable beam splitter 9, the first calibration mirror 6 is moved out, and the second calibration mirror 8 is moved into the optical path corresponding to the second electrically adjustable beam splitter 9 via the third displacement slide 7. The light emitted from the collimator passes through the first electrically adjustable beam splitter 4 and is reflected by the second electrically adjustable beam splitter 9 to the second calibration mirror 8. The mechanical position of the second electrically adjustable beam splitter 9 is adjusted for coarse angle adjustment, and then the angle is finely adjusted using the fine adjustment system of the second electrically adjustable beam splitter 9 itself until the autocollimated image is centered. The calibration of the second electrically adjustable beam splitter 9 is then completed. When there are more than two electrically adjustable beam splitters, the calibration process is the same as the above calibration process. It is only necessary to move the second calibration mirror 8 into the optical path corresponding to the electrically adjustable beam splitter to be calibrated by using the third displacement slide 7. The specific process will not be described in detail here. After all electrically adjustable beam splitters have been calibrated, calibrate electrically adjustable reflector 10: (e.g.) Figure 3 As shown, the second calibration mirror 8 is inserted into the optical path corresponding to the electrically adjustable reflector 10 via the third displacement slide 7. The light from the collimator 3 is reflected by the calibrated first electrically adjustable beam splitter 4 and transmitted through the second electrically adjustable beam splitter 9, and then reflected by the electrically adjustable reflector 10 to the second calibration mirror 8. The mechanical mounting position of the electrically adjustable reflector 10 is adjusted for coarse adjustment of the position angle, and then the fine adjustment of the angle is performed using the fine adjustment system built into the electrically adjustable reflector 10.

[0027] When calibrating multiple sensors, the ratio of the reflective and transmissive films of each electrically adjustable beam splitter can be changed to ensure that the light emitted from the light source can enter the last sensor after passing through the optical path. In this embodiment, when calibrating three sensors, the first electrically adjustable beam splitter 4 has a light transmittance of 75% and a reflectance of 25%; the second electrically adjustable beam splitter 9 has a light transmittance of 67% and a reflectance of 33%; and the electrically adjustable reflector 10 has a reflectance of 99%. When calibrating more sensors, the ratio of the reflective and transmissive films of each electrically adjustable beam splitter can be adaptively adjusted as long as the actual needs are met.

[0028] The specific structures of each electrically adjustable beam splitter and electrically adjustable reflector 10 are all existing technologies, and the specific structures and the processes of coarse and fine adjustment are common knowledge, so they will not be described in detail here.

[0029] For cases requiring calibration of four sensors (N=4), a third electrically adjustable beam splitter can be added between the second electrically adjustable beam splitter 9 and the electrically adjustable reflector 10 in the optical path. This third beam splitter shares the second calibration mirror 8 and the first displacement slide 11 with the second electrically adjustable beam splitter 9 and the electrically adjustable reflector 10. The first displacement slide 11 can be designed for multi-axis independent control to support the movement of any electrically adjustable beam splitter mounted on it, allowing its reflected beam to be individually aligned with a sensor at any position on the turntable 12, thus achieving flexible time-division calibration.

[0030] All components of the large-span photoelectric turntable optical axis calibration device are mounted on a base, which is a six-degree-of-freedom piezoelectric platform capable of translation, pitch, and yaw compensation to address the impact of mechanical deformation on accuracy over long spans and to control errors in manual operation.

[0031] Meanwhile, the optical axis calibration device of the large-span optoelectronic turntable is also equipped with an environmental monitoring and compensation system. The system includes at least one of a temperature sensor, a strain sensor, an infrared thermal imager, and a laser vibration meter installed on the base, as well as a control unit. The control unit is used to control the six-degree-of-freedom piezoelectric platform, the electrically tunable beam splitter group, and the electrically tunable reflector 10 to perform motion compensation based on the sensor data.

[0032] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A device for calibrating the optical axis of a large-span opto-electronic turntable, characterized in that, include: Light source (1); A collimator (2) is used to convert the light emitted by the light source (1) into a parallel beam; Autocollimator (3); The electrically adjustable beam splitter group is composed of at least one electrically adjustable beam splitter cascaded along the optical path; the first electrically adjustable beam splitter is set on the outgoing optical path of the collimator (2), and each electrically adjustable beam splitter is used to split the incident beam into reflected light reflected to a sensor to be calibrated and transmitted light transmitted to the next level optical element. An electrically adjustable reflector (10) is placed on the transmission light path of the last electrically adjustable beam splitter to reflect the incident beam to a sensor to be calibrated. The first displacement slide (11) is used to carry and drive the electrically tunable beam splitter group and the electrically tunable reflector (10) to move; A calibration mirror assembly, including at least one calibration mirror; The calibration displacement stage group includes at least one displacement stage for driving the calibration mirrors in the calibration mirror group to move into or out of the calibration optical path between the autocollimator (3) and the corresponding electrically adjustable beam splitter or electrically adjustable reflector (10).

2. The optical axis calibration device for a large-span photoelectric turntable according to claim 1, characterized in that, The electrically adjustable beam splitter group specifically includes a first electrically adjustable beam splitter (4) and a second electrically adjustable beam splitter (9); the first electrically adjustable beam splitter (4) is disposed on the outgoing light path of the collimator (2), the second electrically adjustable beam splitter (9) is disposed on the transmission light path of the first electrically adjustable beam splitter (4), and the electrically adjustable reflector (10) is disposed on the transmission light path of the second electrically adjustable beam splitter (9).

3. The device of claim 2, wherein, The first electrically adjustable beam splitter (4) has a transmittance greater than its reflectance, and the second electrically adjustable beam splitter (9) has a transmittance greater than its reflectance.

4. The device of claim 1, wherein, The calibration mirror group includes a first calibration mirror (6) and a second calibration mirror (8); the calibration displacement slide group includes a second displacement slide (5) for driving the first calibration mirror (6) and a third displacement slide (7) for driving the second calibration mirror (8).

5. The apparatus of claim 1, wherein, All components of the large-span photoelectric turntable optical axis calibration device are mounted on a base, which is a six-degree-of-freedom piezoelectric platform.

6. The device of claim 5, wherein the device is configured to be mounted on a large span opto-electronic turntable. The device also includes an environmental monitoring and compensation system, which includes at least one of a temperature sensor, a strain sensor, an infrared thermal imager, and a laser vibration meter installed on the base, as well as a control unit; the control unit is used to control the six-degree-of-freedom piezoelectric platform, the electrically tunable beam splitter group, and the electrically tunable reflector (10) to perform motion compensation based on sensor data.

7. The apparatus of claim 1, wherein, The first displacement slide (11) is a multi-axis slide, which can independently drive any electrically adjustable beam splitter and the electrically adjustable reflector (10) in the electrically adjustable beam splitter group to move.

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