A system and method for aligning the optical center of a lens with the center of the photosensitive surface of an imaging sensor

Abstract

A system and method for aligning the optical center of a lens with the center of the photosensitive surface of an imaging sensor. The system includes: a device for adjusting the object to be measured, which is used to carry and fix the object to be measured, and adjust the object to be measured until the imaging of the straight detection line is not bent. The object to be measured includes two straight detection lines with a non-zero included angle, and the straight detection lines are parallel to the X direction or the Y direction; an imaging sensor adjustment device, which is used to fix the imaging sensor and adjust the imaging sensor until the imaging of the straight detection line passes through the center of the photosensitive surface; a lens adjustment device, which is used to fix the lens; wherein, the XY plane is parallel to the photosensitive surface. The present invention realizes the alignment of the optical center of the lens with the center of the photosensitive surface of the imaging sensor by detecting two straight detection lines, with simple and fast operation, and can significantly improve the assembly efficiency and imaging quality.

Description

Technical Field

[0001] The present invention relates to the field of imaging technology, and particularly to a system and method for aligning the optical center of a lens with the center of the photosensitive surface of an imaging sensor. Background Art

[0002] A lens module (such as an endoscope) is a core component for imaging functions, including a lens and an imaging sensor (such as a CMOS or a CCD, taking CMOS as an example hereinafter). Light passes through the lens and is photosensitive on the CMOS, and the optical signal is converted into an electrical signal, and finally output as image information. During the assembly process, it is particularly important to ensure that the optical center of the lens coincides with the center of the photosensitive surface for the edge consistency and image quality of imaging.

[0003] At present, it is very difficult to ensure that the two are completely concentric in a manually assembled lens module. The reason is that in order to ensure that there is no shadow at the edge during imaging, the size of the lens imaging surface is often larger than that of the photosensitive surface, and a slight eccentricity between the optical center of the lens and the center of the CMOS photosensitive surface cannot be distinguished by the naked eye in imaging. Unless a resolution test chart is used to test the resolution around the lens, and the eccentricity and the position of the eccentricity are judged by observing the consistency. However, this method is too complex and cumbersome in operation and is not conducive to the assembly efficiency. Summary of the Invention

[0004] The purpose of the present invention is to provide a system and method for aligning the optical center of a lens with the center of the photosensitive surface of an imaging sensor, which can improve the assembly efficiency and imaging quality.

[0005] The present invention provides a system for aligning the optical center of a lens with the center of the photosensitive surface of an imaging sensor, including:

[0006] A device for adjusting the object to be measured, which is used to carry and fix the object to be measured. The object to be measured includes two straight detection lines with a non-zero included angle, and the straight detection lines are parallel to the X direction or the Y direction. When the imaging of the straight detection line is bent, the device for adjusting the object to be measured adjusts the object to be measured until the imaging of the straight detection line is not bent;

[0007] A device for adjusting the imaging sensor, which is used to fix the imaging sensor. When the imaging of the straight detection line does not pass through the center of the photosensitive surface, the device for adjusting the imaging sensor adjusts the imaging sensor until the imaging of the straight detection line passes through the center of the photosensitive surface;

[0008] A device for adjusting the lens, which is used to fix the lens;

[0009] Wherein, the XY plane is parallel to the photosensitive surface.

[0010] Further, the device for adjusting the object under test includes a stage, a stage X-direction adjustment structure and a stage Y-direction adjustment structure connected to the stage. The stage is a turntable with rotation and fixation functions, which is used to carry and fix the object under test, and can rotate the linear detection line by a certain angle. The stage X-direction adjustment structure and the stage Y-direction adjustment structure are respectively used to drive the stage to drive the object under test to move along the X direction and the Y direction;

[0011] The device for adjusting the imaging sensor includes an imaging sensor fixing structure, an imaging sensor X-direction adjustment structure and an imaging sensor Y-direction adjustment structure connected to the imaging sensor fixing structure. The sensor fixing structure is used to fix the imaging sensor. The imaging sensor X-direction adjustment structure and the imaging sensor Y-direction adjustment structure are respectively used to drive the imaging sensor fixing structure to drive the imaging sensor to move along the X direction and the Y direction.

[0012] Further, the system further includes: a processing device electrically connected to the device for adjusting the object under test, the device for adjusting the imaging sensor and the device for adjusting the lens, which is used to judge whether the imaging of the linear detection line is bent and whether it passes through the center of the photosensitive surface.

[0013] Further, the system further includes: a display device electrically connected to the imaging sensor, which is used to display the imaging of the linear detection line, and judge whether the imaging of the linear detection line is bent and whether it is located at the center of the display area.

[0014] Further, when the imaging of the linear detection line is bent, the device for adjusting the object under test adjusts the object under test according to the first adjustment signal sent by the processing device; when the imaging of the linear detection line does not pass through the center of the photosensitive surface, the device for adjusting the imaging sensor adjusts the imaging sensor according to the second adjustment signal sent by the processing device.

[0015] Further, the system further includes: a processing device and a display device electrically connected to the imaging sensor. The processing device is used to judge whether the imaging of the linear detection line is bent and whether it passes through the center of the photosensitive surface. The display device is used to display the imaging of the linear detection line, and judge whether the imaging of the linear detection line is bent and whether it is located at the center of the display area; when the imaging of the linear detection line is bent, the operator adjusts the device for adjusting the object under test according to the first adjustment signal sent by the processing device. When the imaging of the linear detection line does not pass through the center of the photosensitive surface, the operator adjusts the device for adjusting the imaging sensor according to the second adjustment signal sent by the processing device.

[0016] Further, the first adjustment signal includes the adjustment direction and angle of the device for adjusting the object to be measured, and the second adjustment signal includes the adjustment direction and angle of the device for adjusting the imaging sensor.

[0017] The present invention also provides a method for aligning the optical center of a lens with the center of the photosensitive surface of an imaging sensor, including: placing the object to be measured, with the lens located between the object to be measured and the imaging sensor, and the object to be measured being parallel to the photosensitive surface, including a first detection line and a second detection line that form a non-zero angle and are straight lines; imaging the object to be measured, including: determining whether the images of the first detection line and the second detection line are curved, if the image of the first detection line is curved, adjusting the object to be measured until the image of the first detection line is no longer curved, if the image of the second detection line is curved, adjusting the object to be measured until the image of the second detection line is no longer curved; determining whether the images of the first detection line and the second detection line pass through the center of the photosensitive surface, if the image of the first detection line does not pass through the center of the photosensitive surface, adjusting the imaging sensor until the image of the first detection line passes through the center of the photosensitive surface, if the image of the second detection line does not pass through the center of the photosensitive surface, adjusting the imaging sensor until the image of the second detection line passes through the center of the photosensitive surface.

[0018] Further, the method further includes: establishing an XYZ three-axis coordinate system with the optical center of the lens as the origin, the XY plane being parallel to the photosensitive surface, and the first detection line and the second detection line being parallel to the X direction and the Y direction respectively.

[0019] Further, first image the first detection line, and adjust the object to be measured and the imaging sensor until the image of the first detection line is no longer curved and passes through the center of the photosensitive surface, then image the second detection line, and adjust the object to be measured and the imaging sensor until the image of the second detection line is no longer curved and passes through the center of the photosensitive surface.

[0020] Further, the object to be measured is an object to be measured with a linear feature, the object to be measured is in a straight rod shape, and its overall shape forms the linear feature, and the first detection line and the second detection line are formed by the linear feature before and after the object to be measured rotates by a certain angle;

[0021] Or, the object to be measured is an object to be measured with two linear features forming a non-zero angle, and the first detection line and the second detection line are formed by the two linear features forming a non-zero angle.

[0022] Further, the angle by which the object to be measured rotates is 90 degrees; or, the angle between the two linear features forming a non-zero angle is 90 degrees.

[0023] Further, it is determined whether the images of the first detection line and the second detection line are bent and whether they pass through the center of the photosensitive surface. By imaging the first detection line and the second detection line on a display device electrically connected to the imaging sensor, it is determined whether the images of the first detection line and the second detection line are bent and whether they pass through the center of the display area of the display device; or directly determined by a processing device electrically connected to the imaging sensor.

[0024] The lens optical center and imaging sensor photosensitive surface center alignment system and method provided by the present invention can achieve the alignment of the lens optical center and the imaging sensor photosensitive surface center through the detection of two straight detection lines, with simple and fast operation, and can significantly improve the assembly efficiency and imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of imaging distortion involved in an embodiment of the present invention.

[0026] Figure 2 It is a schematic layout diagram of an object to be measured, an imaging sensor, and a lens in the method for aligning the lens optical center and the imaging sensor photosensitive surface center according to an embodiment of the present invention.

[0027] Figure 3 is Figure 2 A schematic diagram of the image of the first detection line being bent in the method shown.

[0028] Figure 4 is Figure 3 A schematic diagram of the image of the first detection line not being bent but not passing through the center of the photosensitive surface in the method shown.

[0029] Figure 5 is Figure 3 A schematic diagram of the image of the first detection line not being bent and passing through the center of the photosensitive surface in the method shown.

[0030] Figure 6 is Figure 2 A schematic diagram of the image of the second detection line being bent in the method shown.

[0031] Figure 7 is Figure 6 A schematic diagram of the image of the second detection line not being bent but not passing through the center of the photosensitive surface in the method shown.

[0032] Figure 8 is Figure 6 A schematic diagram of the image of the second detection line not being bent and passing through the center of the photosensitive surface in the method shown.

[0033] Figure 9 It is a schematic diagram of the lens optical center and imaging sensor photosensitive surface center alignment system according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] The following will further describe in detail the specific implementation manners of the present invention in conjunction with the accompanying drawings and embodiments. The following embodiments are used to illustrate the present invention, but are not used to limit the scope of the present invention.

[0035] Lens distortion is caused by the inconsistent magnification of different fields of view of the lens, which does not directly affect the clarity of the image, but will cause image deformation. Among them, during the imaging process of the optical lens, it will cause barrel distortion (aberration) of the image, as Figure 1 shown (the same applies to other lenses, and in this embodiment, an endoscope lens is taken as an example). For the distortion of endoscope imaging, it can be seen that the imaging of a straight line that does not pass through the optical center is curved and deformed; while the imaging of a straight line passing through the optical center is still a straight line after imaging and does not deform. Based on this characteristic of lens distortion, this embodiment realizes the alignment of the optical center of the lens with the center of the photosensitive surface of the imaging sensor. The specific description is as follows.

[0036] In this embodiment, the method for aligning the optical center of the lens with the center of the photosensitive surface of the imaging sensor (hereinafter referred to as the photosensitive surface) includes: placing the object to be measured, with the lens located between the object to be measured and the imaging sensor, the object to be measured being parallel to the photosensitive surface and having two straight line detection lines with a non-zero included angle; imaging the object to be measured, including: determining whether the imaging of the two straight line detection lines is curved, and if it is curved, adjusting the object to be measured until the imaging of the straight line detection lines is not curved; determining whether the imaging of the two straight line detection lines passes through the center of the photosensitive surface, and if it does not pass through, adjusting the imaging sensor until the imaging of the straight line detection lines passes through the center of the photosensitive surface. After the imaging of the two detection lines is not curved and passes through the center of the photosensitive surface, the alignment of the optical center of the lens with the center of the photosensitive surface of the imaging sensor is achieved.

[0037] Specifically, the method for aligning the optical center of the lens with the center of the photosensitive surface of the imaging sensor in this embodiment includes the following steps S1 - step S5.

[0038] Step S1, as Figure 2 shown, taking the optical center of lens 2 as the coordinate origin, an XYZ three-axis coordinate system is established, where the XY plane is parallel to the photosensitive surface. Place the object 1 to be measured with a straight line feature in front of lens 2. In this embodiment, the object 1 to be measured is a straight ruler (or other straight rod-shaped object), and its overall shape forms a straight line feature. In other embodiments, the object 1 to be measured can be of other shapes as long as it has a straight line feature, such as a straight line engraved on a flat plate, a straight edge. The imaging sensor 3 is electrically connected to a display device (not shown), and the display device forms a display area 5 on the screen corresponding to the imaging sensor 3. The object 1 to be measured can be imaged in the display device and displayed in the display area 5. Corresponding to Figure 2 the three-axis coordinate system in Figures 3 to 8 the vertical direction corresponds to the X-axis direction, and the horizontal direction corresponds to the Y-axis direction.

[0039] Step S2: Align the linear feature of the object under test 1 parallel to the X-axis direction to form a first detection line; image the object under test 1 ( Figures 3 to 8 the label of the image of the object under test 1 in Figure 4 is 4), and determine whether the image 4 of the first detection line is curved. If the image 4 of the first detection line is not curved (such as Figure 3 ), then proceed to Step S3; if the image 4 of the first detection line is curved (such as Figure 4 ), then adjust the object under test 1 in the direction parallel to the Y-axis until the image 4 of the first detection line is not curved (such as

[0040] Figure 5 ). Figure 4 Figure 4 ), then adjust the imaging sensor 3 in the direction parallel to the Y-axis until the image 4 of the first detection line passes through the center of the photosensitive surface (is located at the center of the display area 5 in the direction parallel to the Y-axis), so as to achieve the alignment of the lens optical center and the center of the photosensitive surface of the imaging sensor in the direction parallel to the Y-axis.

[0041] In the above Steps S2 and S3, image the first detection line parallel to the X-axis direction, determine whether its image is curved and whether it passes through the center of the photosensitive surface, and correspondingly adjust the object under test 1 and the imaging sensor 3 in the Y-axis direction until the image of the first detection line is a straight line (without deformation) and is located at the center of the display area 5. At this time, the lens optical center and the center of the photosensitive surface of the imaging sensor are concentric in the Y-axis direction, that is, the alignment of the lens optical center and the center of the photosensitive surface of the imaging sensor in the Y-axis direction is achieved.

[0042] Step S4: Rotate the object under test 1 so that its linear feature is parallel to the Y-axis direction to form a second detection line; image the object under test 1 and determine whether the image 4 of the second detection line is curved. If the image 4 of the second detection line is not curved (such as Figure 7 ), then proceed to Step S5; if the image 4 of the second detection line is curved (such as Figure 6 ), then adjust the object under test 1 in the direction parallel to the X-axis until the image 4 of the second detection line is not curved (such as Figure 7 ).

[0043] Step S5: Determine whether the image 4 of the second detection line passes through the center of the photosensitive surface. If the image 4 of the second detection line passes through the center of the photosensitive surface, that is, the image 4 on the screen in the direction parallel to the X-axis is located at the center of the display area 5 (such asFigure 8 ), it indicates that in the direction parallel to the X-axis, the optical center of the lens is aligned with the center of the photosensitive surface of the imaging sensor; if the image 4 of the second detection line does not pass through the center of the photosensitive surface, that is, the image 4 on the screen in the direction parallel to the X-axis is not located at the center of the display area 5 (such as Figure 7 ), then adjust the imaging sensor 3 in the direction parallel to the X-axis until the image 4 of the second detection line passes through the center of the photosensitive surface (located at the center of the display area 5 in the direction parallel to the X-axis), so as to achieve the alignment of the optical center of the lens and the center of the photosensitive surface of the imaging sensor in the direction parallel to the X-axis.

[0044] In the above steps S4 and S5, for the image of the second detection line parallel to the Y-axis, judge whether its image is bent and whether it passes through the center of the photosensitive surface, and correspondingly adjust the measured object 1 and the imaging sensor 3 along the X-axis direction until the image of the second detection line is a straight line (without deformation) and is located at the center of the display area 5. At this time, the optical center of the lens and the center of the photosensitive surface of the imaging sensor are concentric in the X-axis direction, that is, the alignment of the optical center of the lens and the center of the photosensitive surface of the imaging sensor in the X-axis direction is achieved.

[0045] Through the above steps S1 to S5, the optical center of the lens and the center of the photosensitive surface of the imaging sensor are concentric in the XY plane, that is, the alignment of the optical center of the lens and the center of the photosensitive surface of the imaging sensor in the XY plane is achieved.

[0046] In this embodiment, the first detection line and the second detection line are formed by rotating a measured object 1 with a linear feature by a certain angle. Of course, in other embodiments, a measured object 1 itself may have two linear features at a certain angle (non-zero included angle) (such as two sides of an object), and the two linear features are used as the first detection line and the second detection line for detection. Two measured objects 1 with linear features can also be used, and the linear features of the two measured objects 1 are respectively used as the first detection line and the second detection line. In short, as long as the measured object contains a plane parallel to the photosensitive surface and has two linear detection lines with a non-zero included angle, the specific implementation method can be adjusted according to the actual situation.

[0047] In this embodiment, the included angle between the above first detection line and the second detection line is 90 degrees, and they are respectively parallel to the X-axis direction and the Y-axis direction. The imaging of this scheme is easy to observe, but the included angle is not limited to 90 degrees. When the first detection line and the second detection line form other non-zero included angles, the alignment of the optical center of the lens and the photosensitive surface center can be achieved through detection.

[0048] In this embodiment, first, the imaging of the first detection line of the object 1 to be measured is performed. After adjusting the object 1 to be measured and the imaging sensor 3 so that the imaging of the first detection line is not bent (not deformed) and passes through the center of the photosensitive surface, the imaging of the second detection line is then performed. The object 1 to be measured and the imaging sensor 3 are adjusted so that the imaging of the second detection line is not bent (not deformed) and passes through the center of the photosensitive surface. That is, the alignment of the optical center of the lens and the center of the photosensitive surface is achieved through two detections of the first detection line and the second detection line respectively. Of course, in other embodiments, it can also be achieved through one detection, that is, the first detection line and the second detection line are detected and correspondingly adjusted simultaneously. For example, if an object 1 to be measured itself has two linear features at a certain angle (non-zero included angle), it is possible to simultaneously detect whether the detection lines formed by these two linear features are bent and whether they pass through the center of the photosensitive surface. The two detections are not limited to the scheme of this embodiment. It is also possible to first detect whether the first detection line is bent, then detect whether the second detection line is bent, then detect whether the first detection line passes through the center of the photosensitive surface, and finally detect whether the second detection line passes through the center of the photosensitive surface. For example, in the case of using two objects to be measured.

[0049] In this embodiment, to determine whether the imaging of the detection line passes through the center of the photosensitive surface, it is obtained by imaging the detection line on the screen and using an intelligent device to assist in determining whether the imaging 4 of the detection line on the screen passes through the center of the display area 5, and the intelligent device is used to determine whether the imaging 4 of the detection line on the screen is bent. Of course, in other embodiments, it is not necessary to image on the screen. Instead, a processing device (such as an intelligent device like a computer) is electrically connected to the imaging sensor 3, and the processing device directly determines whether the imaging of the linear feature is bent and whether it passes through the center of the photosensitive surface.

[0050] Such as Figure 9As shown in the figure, this embodiment also provides a system for aligning the optical center of a lens with the center of the photosensitive surface of an imaging sensor to implement the above method. The system includes a device for adjusting the object to be measured, a device for adjusting the imaging sensor, a device for adjusting the lens, and a processing device and / or a display device. The device for adjusting the object to be measured is used to carry and fix the object to be measured, and the object to be measured includes two straight detection lines with a non-zero included angle. The straight detection lines are parallel to the X direction or the Y direction, and can control the object to be measured to move along the X direction or the Y direction. The device for adjusting the imaging sensor is used to fix the imaging sensor and control the imaging sensor to move along the X direction or the Y direction. The device for adjusting the lens is used to fix the lens and control the lens to move along the X direction or the Y direction. At least one of the device for adjusting the imaging sensor and the device for adjusting the lens can control the imaging sensor to move along the Z direction (in this embodiment, both can move along the Z direction) to assemble the lens and the imaging sensor together after the optical center of the lens is aligned with the center of the sensor, and the imaging quality can be improved by adjusting the distance between the lens and the imaging sensor. The processing device is used to connect to the imaging sensor to determine whether the imaging of the straight detection line is curved and whether it passes through the center of the photosensitive surface. The display device is used to connect to the imaging sensor to display the imaging of the straight detection line of the object to be measured. The Z direction is perpendicular to the XY plane, and the XY plane is parallel to the photosensitive surface, so the Z direction is the direction perpendicular to the photosensitive surface.

[0051] One of the processing device and the display device can be selected or both can be provided. The display device can image the straight detection line on the screen, and with the assistance of a smart device, it can be determined whether the imaging of the straight detection line on the screen passes through the center of the display area 5. The processing device (such as a smart device like a computer) can directly determine whether the imaging of the straight detection line is curved and whether it passes through the center of the photosensitive surface.

[0052] As Figure 9 As shown in the figure, in this embodiment, the device for adjusting the object to be measured includes a stage 11, a stage X-direction adjustment structure 12, and a stage Y-direction adjustment structure 13. The stage 11 is used to carry and fix the object to be measured 40, and can make the straight detection lines of the object to be measured 40 parallel to the X direction or the Y direction respectively. The stage X-direction adjustment structure 12 and the stage Y-direction adjustment structure 13 are connected to the stage 11 and can respectively drive the stage 11 to drive the object to be measured 40 to move along the X direction and the Y direction.

[0053] The imaging sensor adjustment device includes an imaging sensor fixing structure 21, an imaging sensor X-direction adjustment structure 22, an imaging sensor Y-direction adjustment structure (not shown), and an imaging sensor Z-direction adjustment structure 24. The imaging sensor fixing structure 21 is used to fix the imaging sensor (not shown). The imaging sensor X-direction adjustment structure 22, the imaging sensor Y-direction adjustment structure, and the imaging sensor Z-direction adjustment structure 24 are connected to the imaging sensor fixing structure 21 and can respectively drive the imaging sensor fixing structure 21 to drive the imaging sensor to move along the corresponding X-direction, Y-direction, or Z-direction.

[0054] The lens adjustment device includes a lens clamping structure 31, a lens X-direction adjustment structure 32, a lens Y-direction adjustment structure 33, and a lens Z-direction adjustment structure 34. The lens clamping structure 31 is used to clamp and fix the lens (not shown). The lens X-direction adjustment structure 32, the lens Y-direction adjustment structure 33, and the lens Z-direction adjustment structure 34 are connected to the lens clamping structure 31 and can respectively drive the lens clamping structure 31 to drive the lens to move along the corresponding X-direction, Y-direction, or Z-direction.

[0055] During operation, first place the object to be measured 40 on the stage 11 and make its straight detection line parallel to the X-direction (such as Figure 9 ). Detect whether the image is curved. If the image is curved, adjust the position of the object to be measured 40 in the Y-direction through the stage Y-direction adjustment structure 13 until the image is no longer curved. Otherwise, there is no need to adjust the object to be measured 40. Then detect whether the image passes through the center of the photosensitive surface. If the image passes through the center of the photosensitive surface, it indicates that in the X-direction, the optical center of the lens is aligned with the center of the photosensitive surface of the imaging sensor. Otherwise, adjust the position of the imaging sensor in the Y-direction through the imaging sensor Y-direction adjustment structure until the image passes through the center of the photosensitive surface to align the optical center of the lens with the center of the photosensitive surface of the imaging sensor. Then, the object to be measured 40 can be rotated manually or by other means to make its straight detection line parallel to the Y-direction, and a similar operation method as above can be used to align the optical center of the lens with the center of the photosensitive surface of the imaging sensor in the X-direction. Finally, the lens and the imaging sensor can be assembled together through the lens Z-direction adjustment structure 34 or / and the imaging sensor Z-direction adjustment structure 24.

[0056] In this embodiment, the device for adjusting the object under test, the device for adjusting the imaging sensor, and the device for adjusting the lens are all electrically connected to the processing device. The imaging sensor sends the imaging of the straight detection line to the processing device, and the processing device determines whether the imaging of the straight detection line is bent and whether it passes through the center of the photosensitive surface. When the imaging of the straight detection line is bent, the processing device sends a first adjustment signal to the device for adjusting the object under test, and the device for adjusting the object under test adjusts the object under test 40 according to the first adjustment signal. Specifically, when the straight detection line is parallel to the X direction and the imaging of the straight detection line is bent, the processing device sends a first adjustment signal to the Y-direction adjustment structure 13 of the stage to adjust the position of the object under test 40 in the Y direction until the imaging is no longer bent; when the straight detection line is parallel to the Y direction and the imaging of the straight detection line is bent, the processing device sends a first adjustment signal to the X-direction adjustment structure 12 of the stage to adjust the position of the object under test 40 in the X direction until the imaging is no longer bent. When the imaging of the straight detection line does not pass through the center of the photosensitive surface, the processing device sends a second adjustment signal to the device for adjusting the imaging sensor, and the device for adjusting the imaging sensor adjusts the position of the imaging sensor according to the second adjustment signal. Specifically, when the straight detection line is parallel to the X direction and the imaging of the straight detection line does not pass through the center of the photosensitive surface, the processing device sends a second adjustment signal to the Y-direction adjustment structure of the imaging sensor to adjust the position of the imaging sensor in the Y direction until the imaging passes through the center of the photosensitive surface; when the straight detection line is parallel to the Y direction and the imaging of the straight detection line does not pass through the center of the photosensitive surface, the processing device sends a second adjustment signal to the X-direction adjustment structure 22 of the imaging sensor to adjust the position of the imaging sensor in the X direction until the imaging passes through the center of the photosensitive surface. After the adjustment is completed, the processing device sends an assembly signal to the Z-direction adjustment structure 34 of the lens and / or the Z-direction adjustment structure 24 of the imaging sensor to complete the assembly of the lens and the imaging sensor.

[0057] In one embodiment, the stage 11 can be a turntable with rotation and fixation functions. Usually, the object under test 40 is placed on the fixed turntable. When it is necessary to adjust the position of the straight detection line, the turntable can receive the rotation signal from the processing device to achieve a certain angle of rotation.

[0058] In this embodiment, the first adjustment signal includes parameters such as the adjustment direction and angle of the device for adjusting the object under test. The device for adjusting the object under test adjusts according to the first adjustment signal, and the imaging of the straight detection line can be made no longer bent. The second adjustment signal includes parameters such as the adjustment direction and angle of the device for adjusting the imaging sensor. The device for adjusting the imaging sensor adjusts according to the second adjustment signal, and the imaging of the straight detection line can be made to pass through the center of the photosensitive surface.

[0059] In other embodiments, the imaging sensor is electrically connected to the processing device and the display device. The imaging sensor sends the imaging of the straight line detection line to the processing device, and the processing device determines whether the imaging of the straight line detection line is bent and whether it passes through the center of the photosensitive surface. When the imaging of the straight line detection line is bent, the processing device generates the first adjustment signal and sends it to the display device, and the operator adjusts the device to be measured according to the first adjustment signal. When the imaging of the straight line detection line passes through the center of the photosensitive surface, the processing device generates the second adjustment signal and sends it to the display device, and the operator adjusts the imaging sensor adjustment device according to the second adjustment signal. At this time, scales may be formed on each adjustment structure of the device to be measured adjustment device and the imaging sensor adjustment device, so as to facilitate the operation of the operator.

[0060] In this embodiment, the method and system for aligning the optical center of the lens with the center of the photosensitive surface of the imaging sensor realize the alignment of the optical center of the lens with the center of the photosensitive surface of the imaging sensor by detecting two straight line detection lines. This solution is simple and fast to operate, can significantly improve the assembly efficiency, and the center alignment is accurate, which can significantly improve the imaging quality of the lens module.

[0061] In this article, the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", "vertical", "horizontal", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of clearly expressing the technical solution and description, and therefore cannot be construed as a limitation to the present invention.

[0062] In this article, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, and in addition to the listed elements, it may also include other elements not expressly listed.

[0063] As described above, the above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A system for aligning the optical center of a lens with the center of the photosensitive surface of an imaging sensor, characterized in that, Including: A device for adjusting the object to be measured, which is used to carry and fix the object to be measured. The object to be measured includes two straight detection lines with a non-zero included angle, and the straight detection lines are parallel to the X direction or the Y direction. When the imaging of the straight detection line is bent, the object to be measured is adjusted by the device for adjusting the object to be measured until the imaging of the straight detection line is not bent; An imaging sensor adjustment device, which is used to fix the imaging sensor. When the imaging of the straight detection line does not pass through the center of the photosensitive surface, the imaging sensor is adjusted by the imaging sensor adjustment device until the imaging of the straight detection line passes through the center of the photosensitive surface; A lens adjustment device, which is used to fix the lens; Wherein, the XY plane is parallel to the photosensitive surface.

2. The system according to claim 1, wherein The device for adjusting the object to be measured includes a stage, a stage X-direction adjustment structure and a stage Y-direction adjustment structure connected to the stage. The stage is a turntable with rotation and fixation functions, which is used to carry and fix the object to be measured, and can rotate the straight detection line by a certain angle. The stage X-direction adjustment structure and the stage Y-direction adjustment structure are respectively used to drive the stage to drive the object to be measured to move along the X direction and the Y direction; The imaging sensor adjustment device includes an imaging sensor fixing structure, an imaging sensor X-direction adjustment structure and an imaging sensor Y-direction adjustment structure connected to the imaging sensor fixing structure. The sensor fixing structure is used to fix the imaging sensor, and the imaging sensor X-direction adjustment structure and the imaging sensor Y-direction adjustment structure are respectively used to drive the imaging sensor fixing structure to drive the imaging sensor to move along the X direction and the Y direction.

3. The system according to claim 1, wherein The system further includes: a processing device electrically connected to the device for adjusting the object to be measured, the imaging sensor adjustment device and the lens adjustment device, which is used to judge whether the imaging of the straight detection line is bent and whether it passes through the center of the photosensitive surface.

4. The system according to claim 1, characterized in that, The system further includes: a display device electrically connected to the imaging sensor, which is used to display the imaging of the straight detection line, and judge whether the imaging of the straight detection line is bent and whether it is located at the center of the display area.

5. The system according to claim 3, wherein When the imaging of the straight detection line is bent, the device for adjusting the object to be measured adjusts the object to be measured according to the first adjustment signal sent by the processing device; when the imaging of the straight detection line does not pass through the center of the photosensitive surface, the imaging sensor adjustment device adjusts the imaging sensor according to the second adjustment signal sent by the processing device.

6. The system according to claim 1, characterized in that, The system further includes a processing device and a display device electrically connected to the imaging sensor. The processing device is configured to determine whether the imaging of the straight detection line is curved and whether it passes through the center of the photosensitive surface. The display device is configured to display the imaging of the straight detection line and determine whether the imaging of the straight detection line is curved and whether it is located at the center of the display area. When the imaging of the straight detection line is curved, the operator adjusts the device for the object to be measured according to the first adjustment signal sent by the processing device. When the imaging of the straight detection line does not pass through the center of the photosensitive surface, the operator adjusts the imaging sensor adjustment device according to the second adjustment signal sent by the processing device.

7. The system according to claim 5 or 6, characterized in that, The first adjustment signal includes the adjustment direction and angle of the device for the object to be measured, and the second adjustment signal includes the adjustment direction and angle of the imaging sensor adjustment device.

8. A method for aligning the optical center of a lens with the center of the photosensitive surface of an imaging sensor, characterized in that, Comprising: Place the object to be measured, with the lens located between the object to be measured and the imaging sensor. The object to be measured is parallel to the photosensitive surface and includes a first detection line and a second detection line that are straight lines with a non-zero included angle. Image the object to be measured, including: determining whether the imaging of the first detection line and the second detection line is curved. If the imaging of the first detection line is curved, adjust the object to be measured until the imaging of the first detection line is not curved. If the imaging of the second detection line is curved, adjust the object to be measured until the imaging of the second detection line is not curved. Determine whether the imaging of the first detection line and the second detection line passes through the center of the photosensitive surface. If the imaging of the first detection line does not pass through the center of the photosensitive surface, adjust the imaging sensor until the imaging of the first detection line passes through the center of the photosensitive surface. If the imaging of the second detection line does not pass through the center of the photosensitive surface, adjust the imaging sensor until the imaging of the second detection line passes through the center of the photosensitive surface.

9. The method according to claim 8, wherein The method further includes: establishing an XYZ three-axis coordinate system with the optical center of the lens as the origin. The XY plane is parallel to the photosensitive surface, and the first detection line and the second detection line are respectively parallel to the X direction and the Y direction.

10. The method according to claim 9, characterized in that, First image the first detection line, and adjust the object to be measured and the imaging sensor until the imaging of the first detection line is not curved and passes through the center of the photosensitive surface. Then image the second detection line, and adjust the object to be measured and the imaging sensor until the imaging of the second detection line is not curved and passes through the center of the photosensitive surface.

11. The method according to claim 9, characterized in that, The object to be measured is an object to be measured with a straight feature. The object to be measured is in a straight rod shape, and its overall shape forms the straight feature. The first detection line and the second detection line are formed by the straight feature before and after the object to be measured rotates by a certain angle. Alternatively, the object to be measured is an object to be measured with two straight features having a non-zero included angle, and the first detection line and the second detection line are formed by the two straight features having a non-zero included angle.

12. The method according to claim 11, wherein The angle by which the object to be measured rotates is 90 degrees; or, the included angle between the two straight features having a non-zero included angle is 90 degrees.

13. The method according to any one of claims 8 to 12, characterized in that, Determine whether the images of the first detection line and the second detection line are curved and whether they pass through the center of the photosensitive surface. By imaging the first detection line and the second detection line on a display device electrically connected to the imaging sensor, determine whether the images of the first detection line and the second detection line are curved and whether they pass through the center of the display area of the display device; or directly determine through a processing device electrically connected to the imaging sensor.

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