Calibration mechanism for internal reference of camera

Abstract

The invention discloses a camera internal reference calibration mechanism, which comprises a far scale, a near scale, an upper guide rod, a lower guide rod, a support frame and a height adjusting screw, and is characterized in that two ends of the far scale and the near scale are respectively connected with the upper guide rod and the lower guide rod, and the far scale and the near scale can independently and freely slide along the axial direction; the two ends of the upper guide rod and the two ends of the lower guide rod are connected with the supporting frames respectively, the two ends of the upper guide rod and the two ends of the lower guide rod are fixed to the supporting frames through fasteners respectively, so that a supporting structure is formed, and the two ends of the bottom of each supporting frame are connected with height adjusting screws respectively. The height and the balance position of the whole mechanism can be dynamically adjusted by adjusting the height adjusting screw.

Description

Technical Field

[0001] The invention belongs to the technical field of mechanical equipment, and in particular relates to a calibration mechanism for camera intrinsic parameters. Background Art

[0002] With the rapid development of modern industry, consumers have put forward higher and higher requirements for product quality, which has also promoted the widespread application of modern measurement technology in product quality inspection. Secondly, with the rapid development of manufacturing industry, parts with complex surfaces are increasingly appearing in actual industrial production, such as aircraft blades, automobile streamline shape, aircraft wings, etc. Due to the limitations of production environment and conditions, traditional contact measurement methods have been difficult to meet the actual measurement needs, and they have shortcomings such as low measurement efficiency and poor accuracy. Faced with the measurement tasks of these complex surfaces, non-contact measurement methods have gradually been recognized and promoted by industrial production, including optical photogrammetry, coordinate measurement, laser measurement, etc. At present, the main development trends of measurement technology include online measurement, high precision, non-contact, networking, intelligence and high efficiency. Among them, with the development of computer technology and optical technology, binocular measurement methods based on computer vision have developed rapidly, which is referred to as visual measurement technology here. In general, visual measurement technology includes active three-dimensional measurement and passive three-dimensional measurement. Active three-dimensional measurement technology is currently more commonly used, such as intelligent driving of automobiles, automatic identification of lanes, local measurement of engine blades, cell imaging measurement, hand vein recognition, and health status of mechanical devices. At the same time, some related measurement systems have been produced, such as the ATOS Trip Scan three-dimensional object scanner of the German GOM company and the OKII-H-400 of the Japanese company. Regardless of the visual measurement method used, the camera internal parameter calibration is the key link of visual measurement, which directly affects the measurement accuracy. At present, the commonly used calibration method is the calibration plate. First, the image set of the standard calibration plate in different postures is collected. Then, the camera internal and external parameters are obtained by numerical calculation through the relevant algorithm. This method mainly obtains parameters through the design of relevant algorithms. There are many factors affecting the calibration method, and the stability of the calculation results is insufficient. For example, the chessboard imaging posture of the calibration plate may cause the calculation matrix to be ill-conditioned, so that the parameter calculation results do not converge or even diverge. Secondly, the robustness of the current feature point matching algorithm is still insufficient, and the feature matching error may be amplified during the calculation process, thereby affecting the measurement results. Therefore, compared with the above calculation method, hardware calibration is more reliable. The existing hardware calibration has a complex structure, low accuracy, long calibration adjustment time, and poor stability. Summary of the invention

[0003] The purpose of the present invention is to solve the above problems and provide a camera intrinsic parameter calibration mechanism which has a simple structure, is easy to operate, and can achieve high-precision, fast and reliable camera intrinsic parameter calibration.

[0004] In order to solve the above technical problems, the technical solution of the present invention is: a calibration mechanism for camera intrinsic parameters, including a far scale, a near scale, an upper guide rod, a lower guide rod, a support frame and a height adjustment screw, the two ends of the far scale and the near scale are respectively connected to the upper guide rod and the lower guide rod, the far scale and the near scale can slide independently and freely along the axial direction, the two ends of the upper guide rod and the lower guide rod are respectively connected to two support frames, and the two ends of the upper guide rod and the lower guide rod are respectively fixed to the support frames by fasteners, thereby forming a support structure, the two ends of the bottom of each support frame are respectively connected to the height adjustment screws, and the height and balance position of the entire mechanism can be dynamically adjusted by adjusting the height adjustment screws.

[0005] Preferably, the overall structure of the upper guide rod is a slender stepped shaft structure, the middle part is a thin shaft, and the two ends are thick shafts. The two ends of the upper guide rod are respectively designed with shaft end bosses to cooperate with the support frame to form an axial limit. At the same time, fixing threads are respectively designed at both ends. The end of the upper guide rod passes through the support frame and is connected with a fastener to achieve a fixed connection between the upper guide rod and the support frame, thereby forming a stable structure; one shaft end of the upper guide rod is provided with a camera fixing seat, the camera fixing seat is provided with a camera fixing threaded hole, a measuring camera is installed on the camera fixing seat, the measuring camera is fixed to the camera fixing seat through the camera fixing threaded hole, and forms a fixed connection with the upper guide rod.

[0006] Preferably, the overall structure of the lower guide rod is similar to that of the upper guide rod. Compared with the upper guide rod, the lower guide rod does not have a camera fixing seat, and the other structures are exactly the same. Under the joint action of the upper guide rod and the lower guide rod, stable support of the far scale and the near scale can be achieved, and independent axial movement between the two can be guaranteed.

[0007] Preferably, the support frame is a symmetrical "roof" structure as a whole, and an upper guide rod connecting hole is designed on the top of the support frame. The upper guide rod connecting hole is a light hole, which forms a clearance fit with the upper guide rod; the left and right sides of the support frame are respectively designed with the same connecting light holes, which are the lower guide rod connecting hole and the ranging instrument fixing hole, respectively. The lower guide rod connecting hole is used to fix the lower guide rod, and the ranging instrument fixing hole is used to install the ranging instrument. The lower guide rod connecting hole and the ranging instrument fixing hole can be used interchangeably to improve flexibility; the bottom of the support frame is designed with a height adjustment connecting hole, and the height adjustment connecting hole is designed with an internal thread structure, and the height adjustment connecting hole forms a threaded fit with the height adjustment screw.

[0008] Preferably, the near scale comprises a near scale calibration rod, a near scale connecting rod, a near scale reflecting rod and a near scale reflecting plate which are fixedly connected in sequence as one. The end of the near scale calibration rod is provided with a near scale light-through hole. The two ends of the near scale connecting rod are bent, and the bent interior forms a near scale upper fixing hole and a near scale lower fixing hole. The outer portions of the two bent ends of the near scale connecting rod are respectively fixedly connected to the near scale calibration rod and the near scale reflecting rod.

[0009] Preferably, the near scale is a slender rod structure as a whole, the near scale calibration rod, the near scale connecting rod and the near scale reflection rod are located in the same plane; the upper fixing hole of the scale and the lower fixing hole of the near scale are both incomplete circular hole structures, and the upper fixing hole of the scale and the lower fixing hole of the near scale form an axial sliding fit with the upper guide rod and the lower guide rod respectively; the axis of the near scale reflection disk coincides with the axis of the fixing hole of the ranging instrument.

[0010] Preferably, the distant scale comprises a distant scale calibration plate, a distant scale calibration rod, a distant scale connecting rod, a distant scale reflection rod and a distant scale reflection plate which are sequentially fixed together as one, the two ends of the distant scale connecting rod are respectively bent, and the bent interior forms a distant scale upper fixing hole and a distant scale lower fixing hole; the bent exteriors of the two ends of the distant scale connecting rod are respectively fixedly connected to the distant scale calibration rod and the distant scale reflection rod, and the length of the distant scale calibration rod is greater than the length of the near scale calibration rod.

[0011] Preferably, the height adjustment screw includes an adjustment thread section, an external hexagonal nut and a conical tip which are fixedly connected in sequence, and the adjustment thread section forms a threaded fit with the internal thread of the height adjustment connecting hole; the external hexagonal nut can rotate the height adjustment screw, thereby realizing the height adjustment of the entire calibration device; the conical tip is approximately in point contact with the ground, thereby improving the calibration accuracy.

[0012] Preferably, the fastener comprises a gasket and a fastening nut, which are used side by side; the fastener composed of the gasket and the fastening nut is respectively sleeved on both ends of the upper guide rod and the lower guide rod, and is fixed by the fastening nut.

[0013] The beneficial effects of the present invention are:

[0014] 1. The camera intrinsic parameter calibration mechanism provided by the present invention realizes the high-precision, fast and reliable calibration of the camera intrinsic parameter. The near scale and the far scale can be freely moved, and can be used for the measurement tasks of long / short focal length and large field of view, and has the advantages of simple structure and strong adaptability.

[0015] 2. The present invention can quickly obtain the camera internal parameters by directly reading the positions of the far scale and the near scale, and has the advantages of high precision and good reliability.

[0016] 3. The present invention is mainly used for visual measurement of geometric dimensions of mechanical parts and components, and can provide a simple and accurate internal parameter calibration method for an imaging subsystem (usually a camera objective), thereby improving the visual measurement accuracy of parts and components, reducing calibration errors, and having the advantages of accuracy and speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of a calibration mechanism for camera intrinsic parameters of the present invention;

[0018] Figure 2 It is a schematic diagram of the structure of the upper guide rod of the present invention;

[0019] Figure 3 It is a schematic diagram of the structure of the lower guide rod of the present invention;

[0020] Figure 4 It is a schematic diagram of the support frame structure of the present invention;

[0021] Figure 5 It is a schematic diagram of the structure of the near-scale ruler of the present invention;

[0022] Figure 6 It is a structural schematic diagram of the telescaler of the present invention;

[0023] Figure 7 It is a schematic diagram of the structure of the height adjustment screw of the present invention;

[0024] Figure 8 It is a schematic diagram of the exploded structure of the fastener of the present invention.

[0025] Description of the accompanying drawings: 1. Far scale; 2. Near scale; 3. Upper guide rod; 4. Lower guide rod; 5. Support frame; 6. Height adjustment screw; 7. Fastener; 11. Far scale calibration plate; 12. Far scale calibration rod; 13. Far scale connecting rod; 14. Far scale reflection rod; 15. Far scale reflection plate; 16. Far scale upper fixing hole; 17. Far scale lower fixing hole; 21. Near scale calibration rod; 22. Near scale connecting rod; 23. Near scale reflection rod; 24. Near scale reflection plate Shooting disc; 25, near scale light hole; 26, near scale upper fixing hole; 27, near scale lower fixing hole; 31, shaft end boss; 32, fixing thread; 33, camera fixing seat; 51, upper guide rod connecting hole; 52, lower guide rod connecting hole; 53, distance measuring instrument fixing hole; 54, height adjustment connecting hole; 55, waist groove; 61, adjustment thread section; 62, external hexagonal nut; 63, conical tip; 71, gasket; 72, fastening nut; 331, camera fixing thread hole. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments:

[0027] like Figures 1 to 8As shown, a camera intrinsic parameter calibration mechanism provided by the present invention comprises a far scale 1, a near scale 2, an upper guide rod 3, a lower guide rod 4, a support frame 5 and a height adjustment screw 6, wherein the two ends of the far scale 1 and the near scale 2 are respectively connected to the upper guide rod 3 and the lower guide rod 4, and the far scale 1 and the near scale 2 can slide independently and freely along the axial direction, and the two ends of the upper guide rod 3 and the lower guide rod 4 are respectively connected to the two support frames 5, and the two ends of the upper guide rod 3 and the lower guide rod 4 are respectively fixed to the support frames 5 by fasteners 7, thereby forming a support structure, and the two ends of the bottom of each support frame 5 are respectively connected to the height adjustment screws 6, and the height and balance position of the entire mechanism can be dynamically adjusted by adjusting the height adjustment screws 6.

[0028] like Figure 2 As shown, the overall structure of the upper guide rod 3 is a slender stepped shaft structure, with a thin shaft in the middle and thick shafts at both ends. The two ends of the upper guide rod 3 are respectively designed with shaft end bosses 31, which are used to cooperate with the support frame 5 to form an axial limit. At the same time, fixed threads 32 are respectively designed at both ends. The ends of the upper guide rod 3 pass through the support frame 5 and are connected to the fasteners 7 to achieve a fixed connection between the upper guide rod 3 and the support frame 5, thereby forming a stable structure. A camera fixing seat 33 is provided at one shaft end of the upper guide rod 3, and a camera fixing threaded hole 331 is provided on the camera fixing seat 33. A measuring camera is installed on the camera fixing seat 33, and the measuring camera is fixed to the camera fixing seat 33 through the camera fixing threaded hole 331, and is fixedly connected to the upper guide rod 3.

[0029] In this embodiment, the measuring camera is fixed to the camera fixing seat 33 through the camera fixing threaded hole 331 by bolt connection, and the bolt passes through the existing measuring camera and then extends into the camera fixing threaded hole 331, thereby fastening the measuring camera to the camera fixing seat 33. In this way, the measuring camera is fixedly connected to the upper guide rod 3. There are four camera fixing threaded holes 331 and they are distributed in a rectangular shape.

[0030] In order to control the measurement accuracy, the upper guide rod 3 is required to have good cylindricity and axial straightness, so that the distance measurement between the far scale 1 and the near scale 2 can be ensured to have very high accuracy. At the same time, the four camera fixing threaded holes 331 on the camera fixing seat 33 should be ensured to have high flatness as much as possible. In addition, the axes of the four camera fixing threaded holes 331 and the axis of the upper guide rod 3 have high verticality requirements, so that the upper guide rod 3 can be ensured to have high axial positioning accuracy.

[0031] like Figure 3 As shown, the overall structure of the lower guide rod 4 is similar to that of the upper guide rod 3. Compared with the upper guide rod 3, the lower guide rod 4 does not have a camera fixing seat 33, and the remaining structures are exactly the same. Under the joint action of the upper guide rod 3 and the lower guide rod 4, stable support of the far scale 1 and the near scale 2 can be achieved, and independent axial movement between the two can be guaranteed.

[0032] Under the joint action of the upper guide rod 3 and the lower guide rod 4, the far scale 1 and the near scale 2 can be stably supported, and the axial independent movement between the two can be ensured.

[0033] like Figure 4 As shown, the support frame 5 is generally a symmetrical "roof" structure, and the cross section of the support frame 5 is in the shape of an arrow. The top of the support frame 5 is designed with an upper guide rod connection hole 51, which is a light hole and forms a clearance fit with the upper guide rod 3. The left and right sides of the support frame 5 are respectively designed with the same connection light holes, which are the lower guide rod connection hole 52 and the distance measuring instrument fixing hole 53. The lower guide rod connection hole 52 is used to fix the lower guide rod 4, and the distance measuring instrument fixing hole 53 is used to install the distance measuring instrument. The lower guide rod connection hole 52 and the distance measuring instrument fixing hole 53 can be used interchangeably to improve flexibility. The bottom of the support frame 5 is designed with a height adjustment connection hole 54, and the height adjustment connection hole 54 is designed with an internal thread structure. The height adjustment connection hole 54 forms a threaded fit with the height adjustment screw 6.

[0034] In this embodiment, a waist-shaped groove 55 is provided between the lower guide rod connecting hole 52 and the upper guide rod connecting hole 51. The waist-shaped groove 55 is a through groove structure. There are two waist-shaped grooves 55. The other waist-shaped groove 55 is located between the upper guide rod connecting hole 51 and the ranging instrument fixing hole 53. The two waist-shaped grooves 55 are distributed in an "eight" shape.

[0035] The lower guide rod connection hole 52 and the distance measuring instrument fixing hole 53 can be used interchangeably to improve flexibility. There are two height adjustment connection holes 54, which are distributed at both ends of the bottom of the support frame 5. The height adjustment connection holes 54 cooperate with the height adjustment screws 6 to adjust the height according to actual use conditions to achieve balance. At the same time, the waist-shaped groove 55 structure can reduce weight.

[0036] like Figure 5 As shown, the near scale 2 includes a near scale calibration rod 21, a near scale connecting rod 22, a near scale reflecting rod 23 and a near scale reflecting plate 24 which are fixedly connected in sequence. The end of the near scale calibration rod 21 is provided with a near scale light-through hole 25. The two ends of the near scale connecting rod 22 are bent, and the bent interior forms a near scale upper fixing hole 26 and a near scale lower fixing hole 27. The outer portions of the two ends of the near scale connecting rod 22 are respectively fixedly connected to the near scale calibration rod 21 and the near scale reflecting rod 23.

[0037] The near scale 2 is a slender rod structure as a whole, and the near scale calibration rod 21, the near scale connecting rod 22 and the near scale reflection rod 23 are located in the same plane. The upper fixing hole 26 of the scale and the lower fixing hole 27 of the near scale are both non-complete circular hole structures, and the upper fixing hole 26 of the scale and the lower fixing hole 27 of the near scale respectively form an axial sliding fit with the upper guide rod 3 and the lower guide rod 4. The near scale reflection disk 24 coincides with the axis of the distance measuring instrument fixing hole 53.

[0038] The size of the near-scale light hole 25 can be set independently according to the calibration requirements, but it should have a high processing accuracy. In actual use, in order to ensure the smoothness of relative sliding, lubricating fluid can be applied to the upper guide rod 3 and the lower guide rod 4. The near-scale reflective disk 24 has a high degree of axis coincidence with the rangefinder fixing hole 53. When in use, the near-scale reflective disk 24 can be used to lay a high-brightness reflective thin layer of material, which needs to have a certain degree of flatness.

[0039] like Figure 6 As shown, the telemeter scale 1 includes a telemeter scale calibration plate 11, a telemeter scale calibration rod 12, a telemeter scale connecting rod 13, a telemeter scale reflection rod 14 and a telemeter scale reflection plate 15 which are sequentially fixed together. The two ends of the telemeter scale connecting rod 13 are bent respectively, and the bent interior forms a telemeter scale upper fixing hole 16 and a telemeter scale lower fixing hole 17. The outer portions of the two ends of the telemeter scale connecting rod 13 are respectively fixedly connected to the telemeter scale calibration rod 12 and the telemeter scale reflection rod 14, and the length of the telemeter scale calibration rod 12 is greater than the length of the near scale calibration rod 21.

[0040] In this embodiment, the far scale connecting rod 13 and the near scale connecting rod 22 have the same structure, the far scale reflecting rod 14 and the near scale reflecting rod 23 have the same structure, and the far scale calibration disk 11 is a solid structure.

[0041] like Figure 7 As shown, the height adjustment screw 6 includes an adjustment thread segment 61, an outer hexagonal nut 62 and a conical tip 63 which are fixedly connected in sequence, and the adjustment thread segment 61 forms a threaded fit with the inner thread of the height adjustment connection hole 54. The outer hexagonal nut 62 can rotate the height adjustment screw 6, thereby achieving the height adjustment of the entire calibration device. The conical tip 63 is approximately in point contact with the ground, which can adapt to different application occasions, improve the calibration accuracy, and overcome the influence of the uneven surface of the ground or platform.

[0042] like Figure 8 As shown, the fastener 7 includes a washer 71 and a fastening nut 72, which are used side by side. The fastener 7 consisting of the washer 71 and the fastening nut 72 is respectively sleeved on both ends of the upper guide rod 3 and the lower guide rod 4, and is fixed by the fastening nut 72.

[0043] The number of fasteners 7 is set according to the number of upper guide rods 3 and lower guide rods 4 in actual use, ensuring that the upper guide rods 3, lower guide rods 4 are stably connected to the support frame 5 without loosening, etc., to avoid affecting the final measurement result due to the instability of the entire equipment.

[0044] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. A camera intrinsic parameter calibration mechanism, characterized in that: The invention comprises a far scale (1), a near scale (2), an upper guide rod (3), a lower guide rod (4), a support frame (5) and a height adjustment screw (6). The two ends of the far scale (1) and the near scale (2) are respectively connected to the upper guide rod (3) and the lower guide rod (4). The far scale (1) and the near scale (2) can slide independently and freely along the axial direction. The two ends of the upper guide rod (3) and the lower guide rod (4) are respectively connected to two support frames (5). The two ends of the upper guide rod (3) and the lower guide rod (4) are respectively fixed to the support frames (5) by fasteners (7), thereby forming a support structure. The two ends of the bottom of each support frame (5) are respectively connected to the height adjustment screw (6). By adjusting the height adjustment screw (6), the height and balance position of the entire mechanism can be dynamically adjusted.

2. The camera intrinsic parameter calibration mechanism according to claim 1, characterized in that: The overall structure of the upper guide rod (3) is a slender stepped shaft structure, with a thin shaft in the middle and thick shafts at both ends. The two ends of the upper guide rod (3) are respectively designed with shaft end bosses (31) for cooperating with the support frame (5) to form an axial limit. At the same time, fixing threads (32) are respectively designed at both ends. The end of the upper guide rod (3) passes through the support frame (5) and is connected to the fastener (7) to achieve a fixed connection between the upper guide rod (3) and the support frame (5), thereby forming a stable structure. A camera fixing seat (33) is provided at one shaft end of the upper guide rod (3), and a camera fixing threaded hole (331) is provided on the camera fixing seat (33). A measuring camera is installed on the camera fixing seat (33), and the measuring camera is fixed to the camera fixing seat (33) through the camera fixing threaded hole (331) and is fixedly connected to the upper guide rod (3).

3. The camera intrinsic parameter calibration mechanism according to claim 1, characterized in that: The overall structure of the lower guide rod (4) is similar to that of the upper guide rod (3). Compared with the upper guide rod (3), the lower guide rod (4) does not have a camera fixing seat (33), and the remaining structures of the two are completely the same. Under the joint action of the upper guide rod (3) and the lower guide rod (4), stable support of the far scale (1) and the near scale (2) can be achieved, and axial independent movement between the two can be guaranteed.

4. The camera intrinsic parameter calibration mechanism according to claim 1, characterized in that: The support frame (5) is generally a symmetrical "roof" structure. The top of the support frame (5) is designed with an upper guide rod connection hole (51), which is a light hole and forms a clearance fit with the upper guide rod (3). The left and right sides of the support frame (5) are respectively designed with the same connection light holes, which are the lower guide rod connection hole (52) and the distance measuring instrument fixing hole (53). The lower guide rod connection hole (52) is used to fix the lower guide rod (4), and the distance measuring instrument fixing hole (53) is used to install the distance measuring instrument. The lower guide rod connection hole (52) and the distance measuring instrument fixing hole (53) can be used interchangeably to improve flexibility. The bottom of the support frame (5) is designed with a height adjustment connection hole (54), and the height adjustment connection hole (54) is designed with an internal thread structure. The height adjustment connection hole (54) forms a thread fit with the height adjustment screw (6).

5. The camera intrinsic parameter calibration mechanism according to claim 1, characterized in that: The near scale (2) comprises a near scale calibration rod (21), a near scale connecting rod (22), a near scale reflection rod (23) and a near scale reflection plate (24) which are fixedly connected in sequence. The end of the near scale calibration rod (21) is provided with a near scale light-through hole (25). The two ends of the near scale connecting rod (22) are bent, and the bent interior forms a near scale upper fixing hole (26) and a near scale lower fixing hole (27). The bent exteriors of the two ends of the near scale connecting rod (22) are respectively fixedly connected to the near scale calibration rod (21) and the near scale reflection rod (23).

6. The camera intrinsic parameter calibration mechanism according to claim 5, characterized in that: The near scale (2) is a slender rod structure as a whole, and the near scale calibration rod (21), the near scale connecting rod (22) and the near scale reflection rod (23) are located in the same plane; the upper fixing hole (26) of the scale and the lower fixing hole (27) of the near scale are both incomplete circular hole structures, and the upper fixing hole (26) of the scale and the lower fixing hole (27) of the near scale respectively form an axial sliding fit with the upper guide rod (3) and the lower guide rod (4); the axis of the near scale reflection disk (24) coincides with the axis of the distance measuring instrument fixing hole (53).

7. The camera intrinsic parameter calibration mechanism according to claim 5, characterized in that: The remote scale (1) comprises a remote scale calibration plate (11), a remote scale calibration rod (12), a remote scale connecting rod (13), a remote scale reflection rod (14) and a remote scale reflection plate (15) which are fixedly connected in sequence. The two ends of the remote scale connecting rod (13) are respectively bent, and the bent interior forms a remote scale upper fixing hole (16) and a remote scale lower fixing hole (17); the bent exteriors of the two ends of the remote scale connecting rod (13) are respectively fixedly connected to the remote scale calibration rod (12) and the remote scale reflection rod (14), and the length of the remote scale calibration rod (12) is greater than the length of the near scale calibration rod (21).

8. The camera intrinsic parameter calibration mechanism according to claim 1, characterized in that: The height adjustment screw (6) comprises an adjustment thread section (61), an external hexagonal nut (62) and a conical tip (63) which are fixedly connected in sequence, and the adjustment thread section (61) forms a threaded fit with the internal thread of the height adjustment connection hole (54); the external hexagonal nut (62) can rotate the height adjustment screw (6), thereby achieving height adjustment of the entire calibration device; the conical tip (63) is approximately in point contact with the ground, thereby improving calibration accuracy.

9. The camera intrinsic parameter calibration mechanism according to claim 1, characterized in that: The fastener (7) comprises a gasket (71) and a fastening nut (72), which are used side by side. The fastener (7) composed of the gasket (71) and the fastening nut (72) is respectively sleeved on both ends of the upper guide rod (3) and the lower guide rod (4) and fixed by the fastening nut (72).

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