A method and device for calibrating the consistency of the axis of a target scope

Abstract

The present invention relates to a method and device for calibrating the consistency of the axis of a target scope, the method comprising: obtaining a graticule image with cross marks; the graticule image is an image of the target scope in the lens barrel after mechanical calibration; preprocessing the graticule image in sequence; extracting edge information from the preprocessed graticule image to obtain the edge image; calibrating the cross marks in the edge image to obtain the endpoint coordinate values ​​of the cross marks; calculating the center coordinate values ​​of the cross marks according to the endpoint coordinate values; calculating the mechanical axis coordinates according to the edge image; calculating the deviation value according to the center coordinate value and the mechanical axis coordinates; calibrating the consistency of the axis of the target scope according to the deviation value. The present invention improves the adjustment efficiency and accuracy of the axis consistency calibration process by performing image processing on the image after mechanical calibration.

Description

Technical Field

[0001] The invention relates to the technical field of metrology calibration, and in particular to a method and device for calibrating the consistency of a target mirror axis. Background Art

[0002] The existing target scope axis consistency calibration device is designed for several existing target scope models, and no calibration space is reserved for longer target scopes; it is usually designed to be non-detachable, which is extremely inconvenient to use and carry; there are few adjustable parts, and there is no leveling and calibration mechanism, so it can only rely too much on early mechanical processing, resulting in it being only suitable for experimental use and not suitable for production and actual application; moreover, the application of computer software in the existing target scope calibration process is low, and most of the work relies on manual operation and judgment, with very low accuracy and efficiency, and high technical threshold requirements for operators. Summary of the invention

[0003] The purpose of the present invention is to provide a method and device for calibrating the consistency of the axis of a target scope, which can improve the adjustment efficiency and accuracy of the axis consistency calibration process.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] A method for calibrating the consistency of a target scope axis, comprising:

[0006] Acquire a reticle image with crosshairs; the reticle image is an image of the target calibration mirror in the lens barrel after mechanical calibration;

[0007] Preprocessing the graticule images in sequence;

[0008] Extracting edge information from the preprocessed graticule image to obtain the edge image;

[0009] Calibrate the cross-marked lines in the edge image to obtain the endpoint coordinate values ​​of the cross-marked lines;

[0010] Calculate the center coordinate value of the cross mark according to the endpoint coordinate value;

[0011] Calculating the mechanical axis coordinates according to the edge image;

[0012] Calculate the deviation value according to the center coordinate value and the mechanical axis coordinate;

[0013] The consistency of the target mirror axis is calibrated according to the deviation value.

[0014] Preferably, the preprocessing of the reticle images in sequence comprises:

[0015] The graticule image is subjected to median filtering, image inversion and image binarization processing in sequence.

[0016] Preferably, extracting edge information from the preprocessed graticule image to obtain the edge image comprises:

[0017] The Sobel operator is used to perform edge detection on the preprocessed graticule image to obtain an edge image of the crosshairs in the graticule image and coordinate values ​​of the edge image.

[0018] Preferably, after extracting edge information from the preprocessed graticule image to obtain the edge image, the step further comprises:

[0019] Morphological image processing is performed on the edge image.

[0020] Preferably, the step of calibrating the cross-marked lines in the edge image to obtain the coordinate values ​​of the straight line endpoints of the cross-marked lines includes:

[0021] Performing straight line detection on the cross-marked lines in the edge image using Hough transform to obtain a straight line detection graph;

[0022] The endpoint coordinate values ​​of the four line segments in the cross-marked line are calculated according to the straight line detection diagram.

[0023] Preferably, the method for calculating the center coordinate value of the cross mark according to the endpoint coordinate value is specifically as follows:

[0024]

[0025]

[0026] Among them, X is the horizontal coordinate of the center coordinate value, Y is the vertical coordinate of the center coordinate value, and X a is the horizontal coordinate value of the first line segment, X b is the horizontal coordinate value of the second line segment, Y c is the ordinate value of the third line segment, Y d is the ordinate value of the fourth line segment.

[0027] Preferably, the method for calculating the mechanical axis coordinates according to the edge image is specifically:

[0028]

[0029]

[0030] Among them, Z is the horizontal coordinate of the mechanical axis, K is the vertical coordinate of the mechanical axis, and X min is the minimum horizontal coordinate value of the edge image, X maxis the maximum horizontal coordinate value of the edge image, Y min is the minimum ordinate value of the edge image, Y max is the maximum ordinate value of the edge image.

[0031] Preferably, the method for calculating the deviation value according to the center coordinate value and the mechanical axis coordinate is specifically:

[0032] P=XZ

[0033] Q=YK

[0034] Among them, P is the horizontal coordinate deviation value, Q is the vertical coordinate deviation value, X is the horizontal coordinate of the center coordinate value, Y is the vertical coordinate of the center coordinate value, Z is the horizontal coordinate of the mechanical axis, and Y is the vertical coordinate of the mechanical axis.

[0035] A target mirror axis consistency calibration device, comprising: an electronic level, a plurality of adjustable bases, an optical flat plate, a scissor-type lifting platform, a two-dimensional CCD autocollimator module, a light source module, a support platform, a digital goniometer, a connecting piece and a computer;

[0036] The electronic level and the light source module are placed on the upper bottom surface of the optical plate; a plurality of the adjustable bases are connected to the lower bottom surface of the optical plate, and the adjustable bases are used to adjust the horizontality of the optical plate according to the indication of the electronic level; the scissor-type lifting platform and the support platform are arranged on the upper bottom surface of the optical plate, and the two-dimensional CCD autocollimator module is arranged above the scissor-type lifting platform; when performing mechanical axis calibration, the digital goniometer is also arranged above the support platform, and the two-dimensional CCD autocollimator module and the digital goniometer are respectively connected to the computer, and the two-dimensional CCD autocollimator module is used to align itself along the axis. The mechanical axis transmits a cross-line signal, and the digital goniometer is used to receive the cross-line signal, collect the image of the cross-line signal and send it to the computer; the computer is used to determine whether the cross-line signal is on the axis of the digital goniometer according to the image of the cross-line signal, and the computer is also used to display the coordinate digital of the mechanical axis; the scissor-type lifting platform is used to adjust the vertical height of the two-dimensional CCD autocollimator module, the support platform is used to adjust the horizontal distance of the digital goniometer based on the axis of the mechanical axis, and the two-dimensional CCD autocollimator module is used to adjust the pitch angle and horizontal rotation angle of the cross-line signal;

[0037] The connecting piece is connected to the rear end of the target scope, the mechanical axis of the connecting piece and the mechanical axis of the target scope are in a straight line, the connecting piece is used to extend into the gun barrel, and the mechanical axis of the connecting piece and the mechanical axis of the gun barrel are in a straight line; the target scope is used to replace the digital goniometer after completing the mechanical axis calibration, the light source module is used to emit light source into the target scope, the two-dimensional CCD autocollimator module receives the image of the graticule with cross marks in the barrel of the target scope and sends it to the computer, and the computer is used to calculate the deviation value of the mechanical axis and the actual optical axis of the target scope by adopting a target scope axis consistency calibration method, so that the consistency of the target scope axis is calibrated according to the deviation value.

[0038] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0039] The present invention discloses a device and method for calibrating the consistency of the axis of a target scope, the method comprising: obtaining a graticule image with cross marks; the graticule image is an image of the target scope in the lens barrel after mechanical calibration; preprocessing the graticule image in sequence; extracting edge information from the preprocessed graticule image to obtain the edge image; calibrating the cross marks in the edge image to obtain the endpoint coordinate values ​​of the cross marks; calculating the center coordinate values ​​of the cross marks according to the endpoint coordinate values; calculating the mechanical axis coordinates according to the edge image; calculating the deviation value according to the center coordinate value and the mechanical axis coordinates; calibrating the consistency of the axis of the target scope according to the deviation value. The present invention improves the adjustment efficiency and accuracy of the axis consistency calibration process by performing image processing on the image after mechanical calibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0041] Figure 1 It is a flow chart of the method for calibrating the consistency of the target scope axis of the present invention;

[0042] Figure 2 A schematic diagram of the intersection of the crosshairs in the embodiment provided by the present invention;

[0043] Figure 3 It is a module connection diagram of the target scope axis consistency calibration device of the present invention;

[0044] Figure 4A schematic diagram of the actual use of the calibration target mirror in the embodiment provided by the present invention;

[0045] Figure 5 This is a schematic diagram of the structure of the connecting piece in the embodiment provided by the present invention, wherein: Figure 5 (a) is the left view of the connector. Figure 5 (b) is the front view of the connector;

[0046] Figure 6 This is a schematic diagram of mechanical calibration adjustment in an embodiment provided by the present invention.

[0047] Explanation of symbols:

[0048] 1-electronic level, 2-adjustable base, 3-optical flat plate, 4-scissor-type lifting platform, 5-two-dimensional CCD autocollimator fixture, 6-CCD autocollimator, 7-light source power supply, 8-point light source, 9-screws, 10-support table, 11-digital goniometer, 12-target mirror, 13-connecting parts, 14-computer, 15-USB communication cable, 16-calibration software, 17-limit card slot, 18-threaded mouth, 19-external thread, 20-limit card mouth, 21-axis line, 22-gun barrel, a-first line segment, b-second line segment, c-third line segment, d-fourth line segment. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] The purpose of the present invention is to provide a method and device for calibrating the consistency of the axis of a target scope, which can improve the adjustment efficiency and accuracy of the axis consistency calibration process.

[0051] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0052] Figure 1 Flow chart of the method for calibrating the consistency of the target mirror axis of the present invention, as shown in Figure 1 As shown, the present invention provides a method for calibrating the consistency of the target mirror axis, comprising:

[0053] Step 100: Acquire a reticle image with crosshairs; the reticle image is an image of the target scope in the lens barrel after mechanical calibration.

[0054] Step 200: pre-process the graticule image in sequence.

[0055] Step 300: extract edge information from the preprocessed graticule image to obtain the edge image.

[0056] Step 400: calibrate the cross-marked lines in the edge image to obtain the endpoint coordinate values ​​of the cross-marked lines.

[0057] Step 500: Calculate the center coordinate value of the cross mark according to the endpoint coordinate value.

[0058] Step 600: Calculate the mechanical axis coordinates according to the edge image.

[0059] Step 700: Calculate a deviation value according to the center coordinate value and the mechanical axis coordinate value.

[0060] Step 800: Calibrate the consistency of the target scope axis according to the deviation value.

[0061] Preferably, step 200 includes:

[0062] The graticule image is subjected to median filtering, image inversion and image binarization processing in sequence.

[0063] Specifically, the present invention implements the image enhancement process in step 200 through calibration software in a computer, uses a median filtering method to retain image details, enhance edge characteristics, and prevent edge blur; inverts the image and swaps the light and dark fields; and performs image binarization processing, with the threshold being an adaptive algorithm threshold.

[0064] Preferably, step 300 includes:

[0065] The Sobel operator is used to perform edge detection on the preprocessed graticule image to obtain an edge image of the crosshairs in the graticule image and coordinate values ​​of the edge image.

[0066] Optionally, step 300 detects edge information of the image and collects the edge information of the image using a Sobel operator. The corresponding image will detect the edges of the crosshairs and the scale lines on the crosshairs.

[0067] Preferably, after step 300, the method further includes:

[0068] Morphological image processing is performed on the edge image.

[0069] Specifically, the morphological image processing is as follows: first, a dilation operation is performed on the image to absorb the residual noise points on the edge of the image crosshairs into the main skeleton of the crosshairs, and then an image corrosion operation is performed to refine the image after the previous dilation, so that the image skeleton becomes thinner to facilitate straight line calibration.

[0070] Preferably, step 400 includes:

[0071] Hough transform is used to perform straight line detection on the cross-marked lines in the edge image to obtain a straight line detection map.

[0072] The endpoint coordinate values ​​of the four line segments in the cross-marked line are calculated according to the straight line detection diagram.

[0073] Specifically, Hough transform is performed on the image to detect straight lines. This algorithm will calculate the coordinates of the two endpoints of the line segment.

[0074] Figure 2 The schematic diagram of the crosshair intersection in the embodiment provided by the present invention is as follows: Figure 2 As shown, the present invention can calculate the center of the crosshairs (cross lines) according to the endpoint coordinate values ​​of the first line segment a, the second line segment b, the third line segment c and the fourth line segment d, and the center of the crosshairs is the coordinate value of the optical center.

[0075] Preferably, the calculation method of step 500 is specifically:

[0076]

[0077]

[0078] Among them, X is the horizontal coordinate of the center coordinate value, Y is the vertical coordinate of the center coordinate value, and X a is the horizontal coordinate value of the first line segment, X b is the horizontal coordinate value of the second line segment, Y c is the ordinate value of the third line segment, Y d is the ordinate value of the fourth line segment.

[0079] Specifically, after calculating the coordinates of the optical center, it is necessary to calculate the deviation between the optical center and the mechanical center, using the mechanical axis of the CCD autocollimator as the reference mechanical axis. Because the CCD autocollimator is used for image acquisition, the center of the acquired image is the same point as the mechanical axis, so it is only necessary to calculate the center coordinates of the image to obtain the coordinates of the mechanical axis.

[0080] Preferably, the calculation method of step 600 is specifically:

[0081]

[0082]

[0083] Among them, Z is the horizontal coordinate of the mechanical axis, K is the vertical coordinate of the mechanical axis, and X min is the minimum horizontal coordinate value of the edge image, X maxis the maximum horizontal coordinate value of the edge image, Y min is the minimum ordinate value of the edge image, Y max is the maximum ordinate value of the edge image.

[0084] Preferably, the calculation method of step 700 is specifically:

[0085] P = XZ;

[0086] Q = YK;

[0087] Among them, P is the horizontal coordinate deviation value, Q is the vertical coordinate deviation value, X is the horizontal coordinate of the center coordinate value, Y is the vertical coordinate of the center coordinate value, Z is the horizontal coordinate of the mechanical axis, and Y is the vertical coordinate of the mechanical axis.

[0088] Specifically, after calculation, the values ​​of P and Q represent the values ​​of deviation, and the positive and negative values ​​of P and Q represent the direction of deviation.

[0089] As an optional implementation, step 800 is to calibrate the consistency of the target scope axis according to the deviation value.

[0090] Specifically, after calculating the deviation pixel distance (deviation value), the pixel deviation needs to be converted into the actual deviation size. The basic unit of measurement for image resolution is dpi, which means the number of pixels P per inch I, that is, the smallest resolvable point, which is the window connecting image information and vision. Because one inch I is 25400μm (2.54cm), and the image is magnified by β times by the microscope system, the conversion formula between pixels N and micrometers M can be obtained as follows:

[0091]

[0092] The magnification β is determined by the fixed parameters of the calibration mirror. The pixel dpi can be viewed through image viewing software. When the key components of the device are selected, the dpi value is determined.

[0093] Substituting the values ​​of P and Q into N respectively, the actual deviation between the mechanical axis and the optical axis of the calibration mirror can be calculated by the above formula. The calibration mirror can be adjusted according to the actual deviation to achieve the consistency calibration of the axis of the calibration mirror.

[0094] Figure 3 This is a module connection diagram of the target mirror axis consistency calibration device of the present invention, as shown in Figure 3 As shown, a target mirror axis consistency calibration device of the present invention includes: an electronic level 1, multiple adjustable bases 2, an optical plate 3, a scissor-type lifting platform 4, a two-dimensional CCD autocollimator module, a light source module, a support platform 10, a digital goniometer 11, a connecting piece 13 and a computer 14.

[0095] The electronic level 1 and the light source module are placed on the upper bottom surface of the optical plate 3; the plurality of adjustable bases 2 are connected to the lower bottom surface of the optical plate 3, and the adjustable base 2 is used to adjust the horizontality of the optical plate 3 according to the indication of the electronic level 1; the scissor-type lifting platform 4 and the support platform 10 are arranged on the upper bottom surface of the optical plate 3, and the two-dimensional CCD autocollimator module is arranged above the scissor-type lifting platform 4; when performing mechanical axis calibration, the digital goniometer 11 is also arranged above the support platform 10, and the two-dimensional CCD autocollimator module and the digital goniometer 11 are respectively connected to the computer 14, and the two-dimensional CCD autocollimator module is used to align the optical axis along the optical plate 3. The mechanical axis thereof emits a cross-line signal, and the digital goniometer 11 is used to receive the cross-line signal, and collect the image of the cross-line signal and send it to the computer 14; the computer 14 is used to determine whether the cross-line signal is on the axis of the digital goniometer 11 according to the image of the cross-line signal, and the computer 14 is also used to display the coordinate digital of the mechanical axis; the scissor-type lifting platform 4 is used to adjust the vertical height of the two-dimensional CCD autocollimator module, and the support platform 10 is used to adjust the horizontal distance of the digital goniometer 11 based on the axis of the mechanical axis, and the two-dimensional CCD autocollimator module is used to adjust the pitch angle and horizontal rotation angle of the cross-line signal.

[0096] The connecting piece 13 is connected to the rear end of the target scope 12, and the mechanical axis of the connecting piece 13 and the mechanical axis of the target scope 12 are in a straight line. The connecting piece 13 is used to extend into the gun barrel 22, and the mechanical axis of the connecting piece 13 and the mechanical axis of the gun barrel 22 are in a straight line; the target scope 12 is used to replace the digital goniometer 11 after completing the mechanical axis calibration, the light source module is used to emit light into the target scope 12, the two-dimensional CCD autocollimator module receives the image of the graticule with cross marks in the barrel of the target scope 12 and sends it to the computer 14, and the computer 14 is used to calculate the deviation value between the mechanical axis and the actual optical axis of the target scope 12, so as to calibrate the consistency of the axis of the target scope 12 according to the deviation value.

[0097] Specifically, during the calibration of the axis consistency of the target mirror 12, all adjustment mechanisms, bearing mechanisms, and optical devices need to be placed on the optical flat plate 3, so the optical flat plate 3 must first be level. The present invention configures an electronic level 1 on the optical flat plate 3, which can display the level of the optical flat plate 3 in real time, and adjusts the optical flat plate 3 through four adjustable bases 2 below the optical flat plate 3. When the electronic level 1 reading shows level, the height of the four adjustable bases 2 is fixed to complete the horizontal calibration of the optical flat plate 3 (wherein the accuracy requirement of the electronic level 1 is 0.01 mm / m).

[0098] Preferably, the computer 14 has a built-in calibration software 16 , and the calibration software 16 is used to perform image processing and deviation calculation according to the first image and the second image to obtain an image offset so as to achieve axis consistency calibration of the calibration target scope 12 .

[0099] Optionally, the two-dimensional CCD autocollimator module includes: a two-dimensional CCD autocollimator fixture 5 and a CCD autocollimator 6; the two-dimensional CCD autocollimator fixture 5 is arranged above the scissor-type lifting platform 4, and the CCD autocollimator 6 is arranged on the two-dimensional CCD autocollimator fixture 5, and the two-dimensional CCD autocollimator fixture 5 is used to adjust the pitch angle and horizontal rotation angle of the CCD autocollimator 6, the CCD autocollimator 6 is connected to the computer 14, and the CCD autocollimator 6 is used to emit a cross-line signal, and the mechanical axis of the CCD autocollimator 6 is on the same straight line as the mechanical axis of the calibration target mirror 12.

[0100] Optionally, the calibration target mirror 12 is an irregular object. In reality, it is difficult to stably clamp the calibration target mirror 12 without affecting the convenience and accuracy of the experiment, and this device requires that the mechanical axis of the calibration target mirror 12 be placed on the same mechanical axis of the CCD autocollimator 6. Therefore, it is necessary to determine the reference plane of the calibration target mirror 12. Combined with the actual use method of the calibration target mirror 12, the method of using the rear end surface of the calibration target mirror 12 as the reference surface is determined.

[0101] Figure 4 The schematic diagram of the actual use of the calibration target mirror 12 in the embodiment provided by the present invention is as follows: Figure 4 As shown, in actual use, the rear end of the calibration scope 12 will be connected to the connector 13 that meets the caliber of the gun barrel 22, and the connector 13 will be inserted into the gun barrel 22. The mechanical axis of the connector 13 and the mechanical axis of the gun barrel 22 are in a straight line, and the mechanical axis of the connector 13 and the mechanical axis of the calibration scope 12 are also in a straight line. Therefore, when calibrating the calibration scope 12, the part where the calibration scope 12 and the connector 13 are connected is determined as the reference plane. This selection is in line with the principle of the calibration scope 12 in actual use. In combination with the customized connector 13 and the customized support 10, this method can fix the calibration scope 12 well and facilitate the subsequent mechanical coaxial realization.

[0102] Figure 5 The schematic diagram of the structure of the connecting member in the embodiment provided by the present invention is as follows: Figure 5 (a) is the left view of the connector. Figure 5(b) is the front view of the connector. The connector 13 is designed as a cylindrical device with the same outer diameter as the digital goniometer 11, with an external thread 19 at the front end, which cooperates with the limit slot 17 at the rear of the calibration mirror 12. The connector 13 is aligned according to the position of the limit slot 17, and the threaded opening 18 at the rear end of the calibration mirror 12 is screwed onto the external thread 19 at the front end of the connector 13 to complete the connection between the calibration mirror 12 and the connector 13. At this time, the mechanical axis of the connector 13 is the same as the mechanical axis of the reference surface selected by the calibration mirror 12.

[0103] Specifically, the CCD autocollimator 6 and the digital goniometer 11 are both connected to the computer 14 via a USB communication line 15 .

[0104] Preferably, the optical plate 3 is provided with a plurality of standard screw holes 9 .

[0105] Optionally, the light source module includes: a light source power supply 7 and a point light source 8 ; the light source power supply 7 is disposed on the optical plate 3 , the light source power supply 7 is used to supply power to the point light source 8 , and the point light source 8 is used to illuminate the calibration mirror 12 .

[0106] Specifically, it also includes a screw 9; the base of the support platform 10 is provided with a slot that moves left and right along the axis of the mechanical axis, and the screw 9 is arranged in the slot. The screw 9 is used to fix the support platform 10 after the position adjustment is determined.

[0107] Optionally, the calibration of the axis consistency of the target mirror 12 requires calibration of the deviation between the mechanical axis and the optical axis of the target mirror 12. The present invention uses the mechanical axis of the CCD autocollimator 6 as the reference axis, so it is necessary to ensure that the support platform 10 cooperates with the target mirror 12 so that the mechanical axis of the target mirror 12 is on the mechanical axis of the CCD autocollimator 6. In order to ensure the coaxiality of the target mirror 12 and the CCD autocollimator 6 when machining coaxiality cannot be achieved, the present invention utilizes a two-way calibration method of the CCD autocollimator 6 and the digital goniometer 11, and cooperates with the two-dimensional CCD autocollimator fixture 5, the scissor-type lifting platform 4 and the support platform 10 that can be adjusted in one dimension to achieve coaxial calibration, such as Figure 6 As shown, the specific process is:

[0108] (1) The CCD autocollimator 6 is used as a signal source to emit a cross-line signal along the mechanical axis. The digital goniometer 11 is used as a receiver on the opposite end. After receiving the cross-line signal, the image collected by the digital goniometer 11 is transmitted to the computer 14, and the software is used to determine whether the emitted signal is on the axis of the digital goniometer 11.

[0109] (2) After software recognition, the coordinates of the mechanical axis can be accurately displayed on the computer 14 screen. At this time, real-time adjustments can be made according to the deviation, using the two-dimensional CCD autocollimator fixture 5 to adjust the pitch angle and horizontal rotation angle, using the scissor-type lifting platform 4 to adjust the vertical lifting direction, and using the one-dimensional adjustable support platform 10 to adjust the horizontal left and right based on the axis 21. After the adjustment of the support platform 10 is completed, the screws 9 in the displacement slot of the base of the support platform 10 are fixed. At this time, the axis of the CCD autocollimator 6 and the axis of the digital goniometer 11 are located on the same straight line.

[0110] Specifically, after completing the mechanical coaxial calibration in the previous step, the digital angle meter is removed from the support 10, and the target mirror 12 connected to the connector 13 is placed on the support 10. Turn on the light source power supply 7, turn on the light source 8, and extend the lamp head of the light source into the eyepiece of the target mirror 12. At this time, the graticule with engraved lines in the barrel of the target mirror 12 will be illuminated by the light source of the power supply, and the image of the graticule will pass through the objective end of the target mirror 12 into the light pipe of the CCD autocollimator 6 and be collected by the CCD autocollimator 6. The collected image is the graticule image with cross engraved lines. In the image, the background is the bright field of view, and the cross hairs are the dark field of view. This image is transmitted to the computer 14 via the USB communication line 15, and the image is processed using the prepared calibration software 16.

[0111] As an optional implementation, the computer 14 is a portable computer 14 or a desktop computer 14 .

[0112] The beneficial effects of the present invention are as follows:

[0113] (1) The optical platform is calibrated using a high-precision electronic level, which provides a more accurate calibration environment for the subsequent calibration of the target mirror. In addition, the electronic level can display the level in real time, which improves the adjustment efficiency.

[0114] (2) The adjustable base can adapt to different calibration environments and is more suitable for outdoor experiments of calibration devices than the traditional fixed base.

[0115] (3) In the processing of the mechanical axis, the method of combining image processing with four-dimensional adjustment is adopted to avoid the processing difficulty caused by the excessively high requirements for mechanical processing accuracy; to avoid module damage caused by long-term use of the device, unsuitable experimental environment, improper use, and improper storage, which affects the final calibration results. The environmental adaptability is higher and the service life is longer.

[0116] (4) The mechanical axis calibration process is software-assisted and data is visualized, which greatly reduces the operational threshold during the calibration process. The operator only needs to make corresponding adjustments based on the software readings, greatly improving the adjustment efficiency.

[0117] (5) The digital goniometer used in mechanical axis calibration has high accuracy and can bring higher accuracy than simple mechanical processing, reducing the impact on the subsequent calibration of the target mirror axis consistency.

[0118] (6) Instead of using a customized base, an optical flat plate is used as the carrier platform. The advantage is that different levels of optical flat plates can be selected according to the calibration requirements of different target scopes. This has greater adaptability and can also save costs in low-precision calibration experiments.

[0119] (7) The optical plate has standard screw holes, which is more suitable for the installation of optical equipment. For example, if there are different sizes of target mirrors that need to be calibrated for axis consistency, the extra holes can provide a longer calibration distance.

[0120] (8) The optical flat plate is used as a calibration platform, which allows for better equipment disassembly. Different components can be stored in modules when not in use, which increases portability and greatly improves maintainability.

[0121] (9) A CCD autocollimator is used for image acquisition. The accuracy of the CCD autocollimator can be selected. To meet different calibration requirements, only the CCD autocollimator needs to be replaced, and there is no need to redesign the entire system structure, which saves costs.

[0122] (10) The CCD autocollimator is an integrated design of a CCD camera and a parallel light tube. During the calibration process, vibrations may occur due to the installation. The integrated design can avoid the deviation of the camera sensor end face and the mechanical axis of the light tube caused by vibrations.

[0123] (11) Using a computer as the image processing end can improve calibration efficiency.

[0124] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0125] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A target mirror axis consistency calibration device, characterized in that: include: Electronic level, multiple adjustable bases, optical flatbed, scissor lift, 2D CCD autocollimator module, light source module, support, digital goniometer, connectors and computer; The electronic level and the light source module are placed on the upper bottom surface of the optical plate; a plurality of the adjustable bases are connected to the lower bottom surface of the optical plate, and the adjustable bases are used to adjust the horizontality of the optical plate according to the indication of the electronic level; the scissor-type lifting platform and the support platform are arranged on the upper bottom surface of the optical plate, and the two-dimensional CCD autocollimator module is arranged above the scissor-type lifting platform; when performing mechanical axis calibration, the digital goniometer is also arranged above the support platform, and the two-dimensional CCD autocollimator module and the digital goniometer are respectively connected to the computer, and the two-dimensional CCD autocollimator module is used to align itself along the axis. The mechanical axis transmits a cross-line signal, and the digital goniometer is used to receive the cross-line signal, collect the image of the cross-line signal and send it to the computer; the computer is used to determine whether the cross-line signal is on the axis of the digital goniometer according to the image of the cross-line signal, and the computer is also used to display the coordinate digital of the mechanical axis; the scissor-type lifting platform is used to adjust the vertical height of the two-dimensional CCD autocollimator module, the support platform is used to adjust the horizontal distance of the digital goniometer based on the axis of the mechanical axis, and the two-dimensional CCD autocollimator module is used to adjust the pitch angle and horizontal rotation angle of the cross-line signal; The connecting piece is connected to the rear end of the target scope, the mechanical axis of the connecting piece and the mechanical axis of the target scope are in a straight line, the connecting piece is used to extend into the gun barrel, and the mechanical axis of the connecting piece and the mechanical axis of the gun barrel are in a straight line; the target scope is used to replace the digital goniometer after completing the mechanical axis calibration, the light source module is used to emit light into the target scope, the two-dimensional CCD autocollimator module receives the image of the reticle with cross marks in the barrel of the target scope and sends it to the computer, the computer is used to calculate the deviation value of the mechanical axis and the actual optical axis of the target scope by the method described below, so as to calibrate the consistency of the target scope axis according to the deviation value; The method for calibrating the consistency of the target mirror axis includes: Acquire a reticle image with crosshairs; the reticle image is an image of the target calibration mirror in the lens barrel after mechanical calibration; Preprocessing the graticule images in sequence; Extracting edge information from the preprocessed graticule image to obtain an edge image, including: performing edge detection on the preprocessed graticule image using a Sobel operator to obtain an edge image of a crosshair in the graticule image and coordinate values ​​of the edge image; Calibrate the cross-marked lines in the edge image to obtain the endpoint coordinate values ​​of the cross-marked lines; The center coordinate value of the cross mark is calculated according to the endpoint coordinate value. The specific calculation method is: Among them, X is the horizontal coordinate of the center coordinate value, Y is the vertical coordinate of the center coordinate value, and X a is the horizontal coordinate value of the first line segment, X b is the horizontal coordinate value of the second line segment, Y c is the ordinate value of the third line segment, Y d is the ordinate value of the fourth line segment; The mechanical axis coordinates are calculated according to the edge image, and the specific calculation method is: Among them, Z is the horizontal coordinate of the mechanical axis, K is the vertical coordinate of the mechanical axis, and X min is the minimum horizontal coordinate value of the edge image, X max is the maximum horizontal coordinate value of the edge image, Y min is the minimum ordinate value of the edge image, Y max is the maximum ordinate value of the edge image; Calculate the deviation value according to the center coordinate value and the mechanical axis coordinate; Calibrate the consistency of the target mirror axis according to the deviation value; The sequentially preprocessing of the grating plate images comprises: The graticule image is sequentially subjected to median filtering, image inversion and image binarization processing; After extracting edge information from the preprocessed graticule image to obtain the edge image, the following step further comprises: performing morphological image processing on the edge image; The step of calibrating the cross-marked lines in the edge image to obtain the coordinate values ​​of the straight line endpoints of the cross-marked lines includes: Performing straight line detection on the cross-marked lines in the edge image using Hough transform to obtain a straight line detection graph; Calculating the endpoint coordinate values ​​of the four line segments in the cross-marked line according to the straight line detection diagram; The method for calculating the deviation value according to the center coordinate value and the mechanical axis coordinate is specifically as follows: P=XZ Q=YK Among them, P is the horizontal coordinate deviation value, Q is the vertical coordinate deviation value, X is the horizontal coordinate of the center coordinate value, Y is the vertical coordinate of the center coordinate value, Z is the horizontal coordinate of the mechanical axis, and Y is the vertical coordinate of the mechanical axis.

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