Tool and method for camera lens calibration and device for simulated shooting

Abstract

Provided are a tool and method for camera lens calibration and a device for simulated shooting. The tool for camera lens calibration includes two semi-cylindrical halves; a semicircular groove is formed along the circumference on the inner surface of each half, the distance from the groove to the nearest end of the half is equal to the interval between the back focus adjustment ring and the locking buckle ring, and the width of the groove is equal to the width of the back focus adjustment ring; a first flange is formed along the circumference on the inner surface, the distance from the first flange to the groove is equal to the width of the lens barrel, and the width of the first flange is equal to the interval between the lens barrel and the focusing ring; a second flange is formed along the circumference on the inner surface, the distance from the second flange to the first flange is equal to the width of the focusing ring, and the width of the second flange is equal to the interval between the focusing ring and the aperture adjustment ring; and a locking device for locking the two halves together. According to the present invention, the back focus distance, front focus distance and aperture of the camera lens can be easily standardized and quickly adjusted to the required size and remain unchanged.

Description

Technical Field

[0001] The present invention relates to the lens calibration of a camera used for photographing a chip test seat in a chip manufacturing process, and in particular to a tool and method for camera lens calibration, and a device for simulated photographing by a calibrated camera lens. Background Art

[0002] During the chip manufacturing process, the chip needs to be placed in the chip test seat of the chip testing system for testing. The chip testing system generally includes a test host, a test interface unit extending from one side of the test host, and an actuation pan (AP) arranged above the test host and the test interface unit. When the chip is tested, the actuation pan descends so that the pressing device on the actuation pan presses the chip placed in the test seat of the test interface unit. During chip testing, foreign matter is strictly prohibited from entering the test seat, otherwise it will damage the solder balls or pads on the chip, thereby affecting the performance of the chip. For this reason, a camera is provided on the actuation pan to photograph the test seat located below the actuation pan, so as to judge whether there is foreign matter in the test seat by taking a photo of the test seat. Therefore, the shooting quality of the test seat photo, that is, the clarity of the photo is very critical. The camera lens suitable for industrial production is usually a fixed-focus lens. In order to capture a clear image, the camera lens needs to be adjusted and calibrated (including focusing and adjusting the aperture). However, the existing traditional lens installation and calibration method usually first installs the camera lens on the charge-coupled device assembly, aligns the target object, and then adjusts the back focus distance, front focus distance and aperture size. This cannot be directly applied to the camera lens in the chip test system because there is not enough space in the chip test system to calibrate the lens of the camera installed on the actuator disk. If the actuator disk with the camera is removed from the chip test system to calibrate the camera lens, the test seat cannot be observed. Therefore, in practice, the camera lens can only be manually calibrated based on experience, which is not only time-consuming and inefficient, but also non-standardized operations that rely on personal experience will lead to poor image quality due to inaccurate focus and poor brightness.

[0003] Therefore, there is a need to improve existing tools and methods for camera lens calibration. Summary of the invention

[0004] The purpose of the present invention is to provide a tool and method for camera lens calibration, and a device for simulating shooting with a calibrated camera lens. The tool and method for camera lens calibration, and the device for simulating shooting with a calibrated camera lens according to the present invention can overcome at least one defect in the above-mentioned prior art.

[0005] According to the present invention, there is provided a tool for calibration of a camera lens to be mounted on a charge coupled device assembly of a camera, wherein:

[0006] The charge coupler assembly comprises a back focus adjustment ring for adjusting the back focus distance of the camera lens and a locking buckle ring for locking the back focus adjustment ring; and

[0007] The camera lens comprises:

[0008] a lens barrel detachably connected to the back focus adjustment ring;

[0009] A focus ring mounted at the other end of the lens barrel and used to adjust the front focal length of the camera lens; and

[0010] An aperture adjustment ring installed on the focus ring and used to adjust the aperture size of the camera lens;

[0011] Characterized in that the tool for camera lens calibration comprises two semi-cylindrical halves;

[0012] A semicircular groove is formed on the inner surface of each of the semi-cylindrical half parts along the circumferential direction, the distance between the semicircular groove and the nearest end of the semi-cylindrical half part is equal to the interval between the back focus adjustment ring and the locking buckle ring, and the width of the semicircular groove is equal to the width of the back focus adjustment ring;

[0013] A first flange is formed on the inner surface of each of the semi-cylindrical half parts adjacent to the semi-circular groove along the circumferential direction, the distance between the first flange and the semi-circular groove is equal to the width of the lens barrel, and the width of the first flange is equal to the interval between the lens barrel and the focusing ring;

[0014] A second flange is formed on the inner surface of each of the semi-cylindrical half portions in close proximity to the first flange along the circumferential direction, the distance between the second flange and the first flange is equal to the width of the focus ring, and the width of the second flange is equal to the interval between the focus ring and the aperture adjustment ring; and

[0015] A locking device is formed on the semi-cylindrical halves and is used to lock the two semi-cylindrical halves together.

[0016] Preferably, the locking device comprises a locking protrusion with a locking hole formed at a middle position on both sides of the outer surface of each of the semi-cylindrical half portions.

[0017] Preferably, the interval between the back focus adjustment ring and the locking buckle, the interval between the lens barrel and the focusing ring, and the interval between the focusing ring and the aperture adjustment ring are empirical values ​​for adjusting the back focus distance, the front focus distance and the aperture size to obtain a clear captured image.

[0018] Preferably, the first flange and / or the second flange is formed in a semicircular shape.

[0019] Preferably, each section of the tool for camera lens calibration separated by the first flange and the second flange has the same inner diameter.

[0020] Preferably, the camera lens is a lens of a camera used to photograph a chip test socket during a chip manufacturing process.

[0021] According to another aspect of the present invention, a method for camera lens calibration is provided, wherein the method uses the tool for camera lens calibration as described above to calibrate the camera lens, and the method comprises:

[0022] Connecting the lens barrel of the camera lens to the back focus adjustment ring of the charge coupled device assembly;

[0023] partially inserting the back focus adjustment ring into the semicircular groove on one of the semi-cylindrical halves of the tool;

[0024] Rotate the focus ring to perform coarse adjustment so that the interval between the lens barrel and the focus ring is substantially equal to the width of the first flange;

[0025] Rotate the aperture adjustment ring so that the interval between the focus ring and the aperture adjustment ring is equal to the width of the second flange;

[0026] Fine-adjusting the focus ring until the interval between the lens barrel and the focus ring is equal to the width of the first flange;

[0027] Pressing the camera lens so that the back focus adjustment ring is completely inserted into the semicircular groove, while the first flange is inserted into the gap between the lens barrel and the focus ring, and the second flange is inserted into the gap between the focus ring and the aperture adjustment ring;

[0028] buckling the other semi-cylindrical half of the tool onto the semi-cylindrical half, and locking the two semi-cylindrical halves together by means of a screw passing through the locking hole of the locking protrusion;

[0029] Rotating the back focus adjustment ring relative to the main cylinder of the CCD assembly until the locking ring abuts against the ends of the two semi-cylindrical halves; and

[0030] The locking buckle ring is locked by using a locking screw passing through a locking hole on the locking buckle ring.

[0031] Preferably, the method further comprises utilizing a device for simulated shooting to allow the calibrated camera lens to perform simulated shooting, wherein the device for simulated shooting is used to simulate a real shooting environment of the camera lens.

[0032] Preferably, whether there is dirt on the lens of the camera lens or whether the lighting source is aged is checked according to the image quality clarity during simulated shooting.

[0033] According to another aspect of the present invention, there is provided a device for simulated shooting, which is used to perform the simulated shooting in the above method, characterized in that the device for simulated shooting comprises:

[0034] Support plate;

[0035] a main body frame movably supported on the support plate; and

[0036] A simulation test seat is arranged on the top end of the main frame.

[0037] Preferably, the support plate is movably supported on the support plate by a threaded spindle.

[0038] Preferably, the support plate is formed with an opening in the middle to accommodate a guide pin on a pressing device of an actuating disk for simulating shooting, and is formed with recesses on both sides to accommodate an illumination light source.

[0039] Preferably, a scale in the vertical direction is provided on the main frame.

[0040] Preferably, a baffle is provided on the other end of the main frame opposite to the end where the camera is provided, so as to shield external light.

[0041] Preferably, three color points of red, yellow and green are respectively arranged at the four vertices and the center of the area of ​​interest on the simulation test seat.

[0042] Preferably, the device for simulated shooting and the camera equipped with the calibrated camera lens are both arranged on an actuator disk for simulated shooting.

[0043] According to the tool and method for camera lens calibration of the present invention, the back focus distance, front focus distance and aperture of the camera lens can be easily standardized and quickly adjusted to the desired sizes and kept unchanged without relying on experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 The camera's charge-coupled device components are shown schematically;

[0045] Figure 2 schematically shows a camera lens mounted to a charge coupled device assembly;

[0046] Figure 3 Another perspective view schematically shows Figure 2 A camera lens mounted to a charge coupled device assembly;

[0047] Figure 4 The relationship between the charge coupled device assembly, the lens of the camera lens, and the object being photographed is schematically shown;

[0048] Figure 5 is a perspective view of a tool for camera lens calibration according to the present invention;

[0049] Figure 6 yes Figure 5 a perspective view of one half of the tool shown;

[0050] Figure 7 Schematically showing the use of the tool for camera lens calibration according to the present invention to lock the charge coupled device assembly and the camera lens in a calibrated position;

[0051] Figure 8 The schematic diagram shows the positional relationship among the pressing device on the actuating disk, the test socket of the test interface unit and the camera after the camera is installed in place on the actuating disk;

[0052] Fig. 9 A device for simulating shooting with a calibrated camera lens is schematically shown;

[0053] Fig.10 yes Fig. 9 Another perspective view of the device shown;

[0054] Fig.11 yes Fig. 9 and Fig.10 A support plate for the device shown;

[0055] Fig.12 yes Fig. 9 and Fig.10 A simulated test socket of the device shown; and

[0056] Fig.13 The diagram schematically shows a simulated shooting process using a calibrated camera lens using the apparatus of the present invention. DETAILED DESCRIPTION

[0057] The preferred embodiments of the present invention are described in detail below with reference to examples. It should be understood by those skilled in the art that these embodiments are exemplary and are not intended to limit the present invention in any way.

[0058] Figure 1 The charge coupled device component (also called CCD image sensor component) of the camera is shown schematically. Figure 1 As shown, the charge coupler assembly 1 of the camera includes a main barrel 3, a circuit board 5 arranged at one end of the main barrel 3, a back focus adjustment ring 7 arranged at the other end of the main barrel 3, and a locking buckle 9 for locking the back focus adjustment ring 7. The charge coupler assembly 1 can be mounted on the camera body by screws passing through the mounting holes 11 on the circuit board 5.

[0059] Figure 2 Schematic showing a camera lens mounted to a charge coupled device assembly, Figure 3 Another perspective view schematically shows Figure 2 The camera lens is mounted on the charge coupled device assembly. Figure 2 and 3 As shown, the camera lens 13 includes a lens barrel 15, a focus ring 17 mounted at one end of the lens barrel 15, an aperture adjustment ring 19 mounted on the focus ring 17, and a lens disposed within the focus ring 17 and / or the aperture adjustment ring 19. The entire camera lens 13 is detachably connected to the back focus adjustment ring 7 of the charge coupler assembly 1 through the other end of the lens barrel 15.

[0060] When taking a photo with a camera, in order to obtain a clear image, in addition to adjusting the aperture size of the lens 13 by the aperture adjustment ring 19 , the lens 13 also needs to be focused. Figure 4 The diagram shows the relationship between the charge coupled device components, the lens of the camera lens, and the object being photographed. Figure 4As shown, focusing includes adjusting the back focus distance S1 from the charge coupler assembly 1 to the lens 21 of the lens and the front focus distance S2 from the lens 21 of the lens to the object 23. For a specific model of camera lens, the back focus distance S1 and the front focus distance S2 are both predetermined, and the lighting conditions are also fixed in industrial applications, and the aperture size is also fixed. Only by adjusting the back focus distance S1 and the front focus distance S2 to predetermined values, and adjusting the aperture to a specific size under specific lighting conditions, can a clear captured image be obtained. The adjustment of the back focus distance S1 is achieved by rotating the back focus adjustment ring 7, the adjustment of the front focus distance S2 is achieved by rotating the focus ring 17, and the adjustment of the aperture is achieved by rotating the aperture adjustment ring 19. For a specific model of camera lens, when the back focus distance S1 and the front focus distance S2 are adjusted to a predetermined value and the aperture is adjusted to a specific size to obtain a clear image, the interval d1 between the back focus adjustment ring 7 and the locking buckle ring 9, the interval d2 between the lens barrel 15 and the focus ring 17, and the interval d3 between the focus ring 17 and the aperture adjustment ring 19 all have corresponding interval fixed values, and these interval fixed values ​​are empirical values ​​that can be obtained through experiments. For example, the actual intervals measured when the back focus adjustment ring 7, the focus ring 17 and the aperture adjustment ring 19 of different lenses of the same model are adjusted multiple times to obtain a clear image can be taken as the final interval fixed value. In addition, the back focus adjustment ring 7, the lens barrel 15 and the focus ring 17 also have corresponding fixed widths W1, W2 and W3, and these fixed widths are unchanged after the camera lens is determined. It is also possible to measure the widths of the back focus adjustment rings, lens barrels and focus rings corresponding to multiple camera lenses of the same model and take the average value as the final fixed width.

[0061] Figure 5 is a perspective view of a tool for camera lens calibration according to the present invention, Figure 6 yes Figure 5 A perspective view of one half of the tool shown. Figure 5 and 6 As shown, the tool 25 for camera lens calibration according to the present invention comprises two semi-cylindrical halves 25a and 25b. Since the two semi-cylindrical halves 25a and 25b have the same shape and structure, only the semi-cylindrical halves 25a will be described below. Figure 6As shown, a semicircular groove 27 is formed along the circumferential direction on the inner surface of the semi-cylindrical half portion 25a, and the distance from the semicircular groove 27 to the nearest end of the semi-cylindrical half portion 25a is T1, T1 is equal to the interval d1 between the back focus adjustment ring 7 and the locking buckle ring 9, and the width T2 of the semicircular groove 27 itself is equal to the width W1 of the back focus adjustment ring 7. A semicircular first flange 29 is formed along the circumferential direction on the inner surface of the semi-cylindrical half portion 25a adjacent to the semicircular groove 27, and the distance from the semicircular first flange 29 to the semicircular groove 27 is T3, T3 is equal to the width W2 of the lens barrel 15, and the width T4 of the semicircular first flange 29 itself is equal to the interval d2 between the lens barrel 15 and the focusing ring 17. A semicircular second flange 31 is formed on the inner surface of the semi-cylindrical half portion 25a adjacent to the semi-circular first flange 29 along the circumferential direction. The distance between the semi-circular second flange 31 and the semi-circular first flange 29 is T5, and T5 is equal to the width W3 of the focus ring 17. The width T6 of the semi-circular second flange 31 itself is equal to the interval d3 between the focus ring 17 and the aperture adjustment ring 19. A locking protrusion 35 with a locking hole 33 is formed in the middle position on both sides of the outer surface of the semi-cylindrical half portion 25a. In a preferred embodiment, the first flange 29 and the second flange 31 are both continuously formed into a semicircle. It should be understood that they can also be formed intermittently or as part of a semicircle. In addition, other forms of locking devices such as a lock buckle can also be provided on the outer surface of the semi-cylindrical half portion 25a to lock the two semi-cylindrical halves together. Figure 3 and 6 As shown, in the present application, the distance T1 from the semicircular groove 27 to the nearest end of the semi-cylindrical half 25a, the width T2 of the semicircular groove 27 itself, the distance T3 from the semicircular first flange 29 to the semicircular groove 27, the width T4 of the semicircular first flange 29 itself, the distance T5 from the semicircular second flange 31 to the semicircular first flange 29, and the width T6 of the semicircular second flange 31 itself are all distances or widths measured along the longitudinal direction of the semi-cylindrical half. The width W1 of the back focus adjustment ring 7, the width W2 of the lens barrel 15, the width W3 of the focus ring 17, the interval d1 between the back focus adjustment ring 7 and the locking buckle 9, the interval d2 between the lens barrel 15 and the focus ring 17, and the interval d3 between the focus ring 17 and the aperture adjustment ring 19 are all widths or intervals measured along the longitudinal direction of the camera lens.

[0062] The following will describe how to calibrate a camera lens using the tool for camera lens calibration of the present invention. Figure 7 Schematically showing locking of a charge coupled device assembly and a camera lens in a calibrated position using the tool for camera lens calibration according to the present invention.

[0063] First, the camera lens 13 is mounted on the charge coupler assembly 1, as shown in FIG. Figure 2 and 3As shown, when installed in place, the lens barrel 15 of the camera lens 13 is tightly against the back focus adjustment ring 7 of the charge coupler assembly 1, so that there is no gap between the lens barrel 15 and the back focus adjustment ring 7. Next, the assembled camera lens 13 and the charge coupler assembly 1 are placed above the half 25a of the tool 25 for camera lens calibration, so that a part of the back focus adjustment ring 7 is inserted into the semicircular groove 27 on the half 25a, and then the focus ring 17 is rotated for coarse adjustment. When the focus ring 17 is rotated, the aperture adjustment ring 19 is fixed relative to the focus ring 17, so that the aperture adjustment ring 19 is rotated with the focus ring 17, so that the gap d2 between the lens barrel 15 and the focus ring 17 is substantially equal to the width T4 of the semicircular first flange 29. Subsequently, the aperture adjustment ring 19 is rotated so that the gap d3 between the focus ring 17 and the aperture adjustment ring 19 is equal to the width T6 of the semicircular second flange 31. Then, the focus ring 17 is finely adjusted until the interval d2 between the lens barrel 15 and the focus ring 17 is just equal to the width T4 of the semicircular first flange 29. At this time, the camera lens 13 is gently pressed so that the back focus adjustment ring 7 is completely inserted into the semicircular groove 27 on the half 25a, and the semicircular first flange 29 is inserted into the gap between the lens barrel 15 and the focus ring 17, and the semicircular second flange 31 is inserted into the gap between the focus ring 17 and the aperture adjustment ring 19. Next, the other half 25b of the tool 25 is buckled onto the half 25a, and the half 25a and the half 25b are tightly locked together by screws passing through the locking holes 33 of the locking protrusions 35 of the half 25a and the half 25b to prevent the focus ring 17 and the aperture adjustment ring 19 from further rotating, as shown in FIG. Figure 7 As shown. Subsequently, the back focus adjustment ring 7 is rotated relative to the main barrel 3 of the charge coupler assembly 1, and the entire camera lens 13 rotates with the back focus adjustment ring 7 relative to the main barrel 3 until the locking buckle 9 of the charge coupler assembly 1 is tightly against the end of the tool 25. At this time, the locking buckle 9 is locked with a locking screw passing through the locking hole 12 on the locking buckle 9 of the charge coupler assembly 1 to prevent the back focus adjustment ring 7 from further rotating relative to the main barrel 3. In this way, according to the tool of the present invention, the back focus distance S1, the front focus distance S2 and the aperture can be easily standardized and quickly adjusted to the desired size without relying on experience and remain unchanged.

[0064] Although a clear image can be obtained by adjusting the back focus distance S1, front focus distance S2 and aperture of the camera lens to the desired size and keeping them unchanged under normal circumstances, some other factors may also affect the image quality. For example, when adjusting the back focus distance S1, front focus distance S2 and / or aperture, dirt may stick to the lens of the lens or insufficient light may be caused by aging of the lighting source, which may also affect the image quality. Therefore, it is necessary to use the lens calibrated by the tool for camera lens calibration of the present invention to perform simulated shooting to eliminate other factors that affect the image quality. However, in the actual use environment, it is difficult to perform simulated shooting due to space limitations.

[0065] Figure 8 The schematic diagram shows the positional relationship between the pressing device on the actuator disk, the test socket of the test interface unit and the camera after the camera is installed on the actuator disk. Although in actual use, the camera is suspended on the actuator disk, in order to facilitate operation when the calibrated camera lens is used for simulated shooting, Fig.13 As shown, the actuator disk for simulating shooting is placed upside down, and the device for simulating shooting with a calibrated camera lens and the camera are normally (non-suspended) arranged on the actuator disk, so that Figure 8 The positional relationship between the pressing device, the test socket and the camera is also displayed in the normal setting. Figure 8 In the figure, the three vertices 37, 39 and 41 of the triangle represent the positions of the pressing device, the test seat and the camera respectively. By measuring, the height H between vertices 37 and 39 (i.e., the distance between the pressing device and the test seat) and the length L between vertices 39 and 41 (i.e., the distance between the test seat and the camera) can be obtained. The angle α obtained according to the tangent formula tanα=H / L is the tilt angle of the camera lens when setting the camera.

[0066] Fig. 9 The apparatus for simulating shooting with a calibrated camera lens is schematically shown. Fig.10 yes Fig. 9 Another perspective view of the device shown, Fig.11 yes Fig. 9 and Fig.10 The support plate of the device shown, Fig.12 yes Fig. 9 and Fig.10 A simulated test socket for the device shown. Figure 9-11As shown, the device 43 for simulating shooting with a calibrated camera lens includes a support plate 45, which is a thin flat plate, and will be placed on the pressing device of the actuator disk, so that an opening 47 is formed in the middle of the support plate 45 to accommodate the guide pin on the pressing device. Preferably, the support plate 45 is formed with recesses 49 on both sides to accommodate the illumination light source. The device 43 for simulating shooting with a calibrated camera lens also includes a main frame 51, which can be movably supported on the support plate 45 through a lead screw 53, and a simulation test seat 55 is arranged at the top of the main frame 51. The distance between the simulation test seat 55 and the support plate 45 corresponds to the distance between the pressing device and the test seat in the actual use environment. The distance between the simulation test seat 55 and the support plate 45 can be adjusted by rotating the position of the lead screw 53 to correspond to the actual distance between the pressing device and the test seat in the actual use environment. In order to facilitate such adjustment, a scale in the vertical direction can be set on the main frame 51. In addition, in order to prevent external light from interfering with imaging, a baffle 57 may be provided at the other end of the main frame 51 opposite to the end where the camera is provided, so as to block external light.

[0067] Fig.13 The device of the present invention is schematically shown to be used for simulated shooting by a calibrated camera lens. Fig.13 As shown, the device 43 for simulating shooting with a calibrated camera lens is arranged on an actuator disk 59 for simulating shooting, so that the support plate 45 is placed on the pressing device of the actuator disk 59, and the main frame 51 is supported on the support plate 45, and the distance between the simulation test seat 55 and the support plate 45 arranged on the main frame 51 is adjusted to be the same as the distance between the pressing device and the test seat in the actual use environment by the lead screw 53. A camera 61 equipped with a lens calibrated and kept fixed by the tool 25 of the present invention is arranged on the actuator disk 59 for simulating shooting, and the distance from the camera 61 to the pressing device of the actuator disk 59 is the same as the distance from the pressing device to the camera in the actual use environment. At the same time, the lens of the camera 61 is tilted at an angle α calculated according to the tangent formula tanα=H / L to ensure that the camera lens images the simulation test seat 55 arranged on the main frame 51 at a suitable angle. As shown Fig. 9 and 10The bottom side of the simulated test seat 55 shown belongs to the object photographed by the camera, and multiple sampling points can be set on the area 63 of concern on the simulated test seat 55, and whether there are other factors affecting the imaging quality can be determined by observing the imaging quality of the sampling points. In a preferred embodiment, three color dots 65 of red, yellow and green are respectively set at the four vertices and the center of the area 63 of concern on the simulated test seat 55, and whether the camera imaging quality is clear can be determined by observing the images of the three color dots of red, yellow and green at these parts. If the camera imaging quality is clear, the camera lens calibrated and kept fixed by the tool of the present invention can be directly applied to the actual test environment. If the camera imaging quality is not clear, it can be checked whether there is dirt on the lens of the camera lens or whether the lighting source is aging, etc., until the problem is eliminated to make the camera imaging quality clear.

[0068] Although the present invention has been described in detail in conjunction with the preferred embodiments of the present invention, it should be understood that such detailed description is only used to explain the present invention and does not constitute a limitation of the present invention. For example, although in the preferred embodiment, the sections of the tool for camera lens calibration separated by the first flange and the second flange have substantially the same inner diameter, in the case where the lens barrel, the focus ring and the aperture adjustment ring of the camera lens have different outer diameters, the sections of the tool for camera lens calibration may have substantially different inner diameters. The scope of the present invention is determined by the technical solutions defined in the claims.

Claims

1. A tool for calibrating a camera lens, the camera lens (13) being adapted to be mounted on a charge coupled device assembly (1) of a camera, wherein: The charge coupler assembly (1) comprises a back focus adjustment ring (7) for adjusting the back focus distance (S1) of the camera lens (13) and a locking buckle ring (9) for locking the back focus adjustment ring (7); as well as The camera lens (13) comprises: A lens barrel (15) detachably connected to the back focus adjustment ring (7); A focus ring (17) mounted at the other end of the lens barrel (15) and used to adjust the front focal length (S2) of the camera lens (13); and An aperture adjustment ring (19) mounted on the focus ring (17) and used to adjust the aperture size of the camera lens (13); Characterized in that the tool (25) for camera lens calibration comprises two semi-cylindrical halves (25a, 25b); A semicircular groove (27) is formed on the inner surface of each of the semi-cylindrical half parts along the circumferential direction, the distance (T1) from the semi-circular groove (27) to the nearest end of the semi-cylindrical half part is equal to the interval (d1) between the back focus adjustment ring (7) and the locking buckle ring (9), and the width (T2) of the semi-circular groove (27) is equal to the width (W1) of the back focus adjustment ring (7); A first flange (29) is formed on the inner surface of each of the semi-cylindrical half portions along the circumferential direction adjacent to the semi-circular groove (27); a distance (T3) from the first flange (29) to the semi-circular groove (27) is equal to a width (W2) of the lens barrel (15); and a width (T4) of the first flange (29) is equal to a spacing (d2) between the lens barrel (15) and the focusing ring (17); A second flange (31) is formed on the inner surface of each of the semi-cylindrical half portions adjacent to the first flange (29) along the circumferential direction, the distance (T5) between the second flange (31) and the first flange (29) being equal to the width (W3) of the focus ring (17), and the width (T6) of the second flange (31) being equal to the interval (d3) between the focus ring (17) and the aperture adjustment ring (19); and A locking device is formed on the semi-cylindrical halves and is used to lock the two semi-cylindrical halves together.

2. The tool for camera lens calibration according to claim 1, characterized in that: The locking device comprises a locking protrusion (35) with a locking hole (33) formed at a middle position on both sides of the outer surface of each semi-cylindrical half.

3. The tool for camera lens calibration according to claim 1, characterized in that: The interval (d1) between the back focus adjustment ring (7) and the locking buckle ring (9), the interval (d2) between the lens barrel (15) and the focus ring (17), and the interval (d3) between the focus ring (17) and the aperture adjustment ring (19) are empirical values ​​when the back focus distance (S1), the front focus distance (S2) and the aperture size are adjusted to obtain a clear captured image.

4. The tool for camera lens calibration according to claim 1, characterized in that: The first flange (29) and / or the second flange (31) are formed in a semicircular shape.

5. The tool for camera lens calibration according to claim 1, characterized in that: The tool (25) for camera lens calibration has the same inner diameter in each section separated by the first flange and the second flange.

6. The tool for camera lens calibration according to claim 1, characterized in that: The camera lens is a lens of a camera used to photograph a chip test socket during the chip manufacturing process.

7. A method for calibrating a camera lens, the method utilizing the tool for calibrating a camera lens as claimed in any one of claims 1 to 6 to calibrate a camera lens, the method comprising: Connecting the lens barrel (15) of the camera lens (13) to the back focus adjustment ring (7) of the charge coupled device assembly (1); Partially inserting the back focus adjustment ring (7) into the semicircular groove (27) on one of the semi-cylindrical halves of the tool (25); Rotating the focus ring (17) for coarse adjustment so that the interval (d2) between the lens barrel (15) and the focus ring (17) is substantially equal to the width (T4) of the first flange (29); Rotating the aperture adjustment ring (19) so that the interval (d3) between the focus ring (17) and the aperture adjustment ring (19) is equal to the width (T6) of the second flange (31); Fine-adjusting the focus ring (17) until the interval (d2) between the lens barrel (15) and the focus ring (17) is equal to the width (T4) of the first flange (29); Pressing the camera lens (13) so that the back focus adjustment ring (7) is completely inserted into the semicircular groove (27), and at the same time the first flange (29) is inserted into the gap between the lens barrel (15) and the focus ring (17), and the second flange (31) is inserted into the gap between the focus ring (17) and the aperture adjustment ring (19); snapping the other semi-cylindrical half of the tool (25) onto the semi-cylindrical half and locking the two semi-cylindrical halves together; Rotating the back focus adjustment ring (7) relative to the main cylinder (3) of the charge coupler assembly (1) until the locking ring (9) abuts against the ends of the two semi-cylindrical halves; and The locking buckle ring (9) is locked by means of a locking screw passing through a locking hole (12) on the locking buckle ring (9).

8. The method for camera lens calibration according to claim 7, characterized in that: The method further comprises using a simulated shooting device to allow the calibrated camera lens to perform simulated shooting, wherein the simulated shooting device is used to simulate a real shooting environment of the camera lens.

9. The method for camera lens calibration according to claim 8, characterized in that: Whether there is dirt on the lens of the camera lens or whether the lighting source is aged is checked according to the image quality clarity during the simulated shooting.

Images