Apparatus and method for determining the eccentric distance of a deflection cemented lens group

Abstract

The application discloses a device and method for measuring deflection cemented lens eccentric distance, which comprises a deflection cemented lens to be measured, a lens tube clamping assembly, an integrating sphere uniform light source, a camera and an auxiliary rotating table. The deflection cemented lens to be measured comprises a deflection prism and a small lens group which are cemented. The lens tube clamping assembly comprises a double-layer lens tube for fixing the deflection cemented lens to be measured. The integrating sphere uniform light source is used to provide uniform light which is converged into a light spot after passing through the deflection cemented lens to be measured. The auxiliary rotating table is used to adjust the camera or the lens tube clamping assembly so that the optical axis of the camera is perpendicular to the top plane of the deflection prism. The distance between the center of the light spot and the center of the small lens group is the eccentric distance of the deflection cemented lens to be measured. The application calculates the deviation between the light spot and the small lens group at the top by means of image recognition, so as to determine the cementing effect of the deflection cemented lens, and greatly improves the assembly efficiency and the yield of the product.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of manufacturing test of deflection cemented lens group, and particularly relates to a device and method for measuring eccentric distance of deflection cemented lens group. BACKGROUND

[0002] With the development of science and technology, endoscopes and rigid tube mirrors develop rapidly. Precise photosensitive components and intelligent image processing and recognition technology are also applied to the development of endoscopes. This also puts forward higher requirements for the mechanical size and optical performance of endoscope optical lenses.

[0003] The thinner the endoscope is, the higher the imaging effect of the internal optical lens of the rigid tube mirror is required. Among them, the objective lens optical group in the endoscope imaging, the bonding effect of the top deflection cemented lens group has a huge impact on the imaging quality.

[0004] The deflection cemented lens group is formed by cementing an angle prism and a small lens at the head, and is the most critical lens in the objective lens group of the endoscope. The internal cementing quality will directly affect the imaging effect of the endoscope. Among them, the eccentric distance of the deflection cemented lens group is a key parameter for judging the internal cementing quality.

[0005] The commonly used reflection type eccentric instrument and projection type eccentric instrument on the market can measure the eccentric distance of coaxial cemented lenses. However, the deflection cemented lens group has an included angle between the internal angle prism and the small lens at the head, so that the optical axis is not a straight line. Therefore, the ordinary eccentric instrument cannot measure the eccentric distance of the deflection cemented lens group.

[0006] The deflection cemented lens group can only be judged whether there is a bonding deviation or a bonding deviation after the internal lens group of the endoscope is completely assembled by imaging the resolution plate. This method is not only low in efficiency, but also introduces other deviations in the overall assembly due to many other lenses in the endoscope. If the final image quality is poor, it is also difficult to analyze the defect and trace the abnormality. SUMMARY

[0007] The purpose of the present application is to provide a device and method for measuring the eccentric distance of the deflection cemented lens group, to solve the problem of measuring the eccentric distance of the deflection cemented lens group, and to determine the quality of the deflection cemented lens group.

[0008] The technical scheme of the present application is as follows:

[0009] A device for measuring the eccentric distance of the deflection cemented lens group, the device comprising a deflection cemented lens group to be measured, a lens tube clamping assembly, an integrating sphere uniform light source, a camera and an auxiliary rotating table;

[0010] The deflection cemented lens group to be measured comprises a deflection prism and a small lens group cemented together;

[0011] The endoscope tube clamping assembly includes a double endoscope tube; wherein, the inner diameter of the outer endoscope tube is slightly larger than the outer diameter of the deflecting prism, the inner diameter of the inner endoscope tube is slightly smaller than the outer diameter of the deflecting prism, and the outer endoscope tube is longer than the inner endoscope tube. The height difference between the inner and outer endoscope tubes forms a step to fix the deflecting cemented endoscope assembly to be tested.

[0012] The integrating sphere uniform light source is connected to the double-layered lens tube to provide uniform light; the uniform light enters the inner lens tube and converges into a single spot after passing through the deflection cemented lens assembly under test.

[0013] The camera is positioned directly above the deflection cemented lens assembly to be tested.

[0014] The auxiliary rotary stage is connected to the camera or lens tube clamping assembly and is used to adjust the camera or lens tube clamping assembly so that the optical axis of the camera is perpendicular to the top plane of the deflecting prism.

[0015] The distance between the center of the light spot and the center of the small lens group is the off-center distance of the deflection cemented lens group to be tested.

[0016] Furthermore, the end of the lens tube clamping assembly also includes claws; the end of the double-layer lens tube that fixes the deflection cemented lens assembly to be tested has multiple slots and a claw-shaped structure that is compatible with the claws.

[0017] After the deflection-cemented lens assembly to be tested is placed in the double-layered lens tube, the clasps clamp the assembly to secure it.

[0018] Furthermore, the gripper is an electric gripper.

[0019] Furthermore, the lens tube clamping assembly also includes a first flange; the first flange is located at the light inlet of the double-layer lens tube;

[0020] The light outlet of the integrating sphere uniform light source is equipped with a second flange, and the first flange and the second flange are connected by bolts.

[0021] Furthermore, the endoscope tube clamping assembly also includes an auxiliary support structure; the auxiliary support structure is located in the upper middle part of the double-layer endoscope tube and provides auxiliary support force.

[0022] Furthermore, the auxiliary rotary table is connected to the auxiliary support structure to adjust the camera or lens tube clamping assembly so that the optical axis of the camera is perpendicular to the top plane of the deflecting prism.

[0023] Furthermore, the camera includes an image sensor and an autofocus lens.

[0024] A method for measuring the eccentricity of a deflecting cemented lens assembly using the apparatus described in any one of the above-mentioned methods includes the following steps:

[0025] The deflection-tested cemented lens assembly is placed in a double-layered lens tube;

[0026] The integral sphere uniform light source provides uniform light, which is converged into a light spot after passing through the deflection cemented lens group to be measured;

[0027] The auxiliary rotating table is adjusted to make the outer contour of the small lens group circular;

[0028] The distance between the center of the light spot and the center of the small lens group is calculated, that is, the eccentric distance of the deflection cemented lens group to be measured.

[0029] Further, the center of the light spot and the center of the small lens group are identified by image recognition.

[0030] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0031] The projection type eccentricity instrument and the reflection type eccentricity instrument on the market cannot measure the eccentric distance of the deflection cemented lens group in a non-coaxial manner. The present application provides an automatic device and method for measuring the eccentric distance of the deflection cemented lens group. The deviation between the light spot and the small lens group at the top is calculated by image recognition, so as to determine the cementing effect of the deflection cemented lens group. The present application will be beneficial to the detection of the deflection cemented lens group, and can confirm whether the deflection cemented lens group meets the optical performance and whether it can proceed to the next process. The present application will greatly improve the assembly efficiency and the yield of the product, and the image recognition method can also ensure the imaging consistency and stability of the deflection cemented lens group during subsequent assembly into a product. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 It is a device structure diagram for measuring the eccentric distance of the deflection cemented lens group of the present application;

[0033] Figure 2 It is a position schematic diagram of the deflection cemented lens group and the double-layer mirror tube of the present application;

[0034] Figure 3 It is a schematic diagram of image recognition of the center of the light spot and the physical center of the small lens group of the present application;

[0035] Figure 4 It is a flow chart of the method for measuring the eccentric distance of the deflection cemented lens group of the present application.

[0036] In the figure: 1-deflection cemented lens group, 11-small lens group, 12-deflection prism, 2-lens clamping assembly, 21-double-layer mirror tube, 211-outer layer mirror tube, 212-inner layer mirror tube, 22-electric chuck, 23-mirror tube flange plate, 24-assistant support structure, 3-integral sphere uniform light source, 4-assistant rotating table, 5-camera, 111-outer contour of small lens group, 112-center of small lens group outer contour, 6-light spot, 61-light spot contour, 62-center of light spot contour. DETAILED DESCRIPTION

[0037] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application. In addition, the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0038] The present application provides a device and method for measuring the eccentric distance of a deflection cemented lens group, specifically, a uniform light source is placed at the bottom of the deflection cemented lens group, and the uniform light will form a light spot at the upper part after passing through the deflection cemented lens group. The physical center deviation of the light spot center and the small lens group at the head of the deflection cemented lens group is calculated by image recognition, and the quality of the deflection cemented lens group is determined by the position difference between the two points.

[0039] The present application will be beneficial to the deflection cemented lens group, confirming whether it meets the optical performance and determining whether it can proceed to the next process. The present application will greatly improve the assembly efficiency and yield of the product, and the use of image recognition can also ensure the stability of the deflection cemented lens group.

[0040] The device for measuring the eccentric distance of the deflection cemented lens group of the present application, as shown in Figure 1 and Figure 2 , comprises a deflection cemented lens group 1 to be measured, a lens tube clamping assembly 2, an integrating sphere uniform light source 3, a camera 5 and an auxiliary rotating table 4.

[0041] The deflection cemented lens group 1 to be measured is formed by cementing a deflection prism 12 and a small lens group 11.

[0042] The lens clamping assembly 2 comprises a double-layer lens tube 21, an electric jaw 22, a lens tube flange 23 and an auxiliary support structure 24.

[0043] The double-layer lens tube 21 is a two-layer through cylinder, and the double-layer lens tube 21 is used to simulate the actual application scene of the deflection cemented lens group to be measured. The inner diameter of the outer lens tube 211 is slightly larger than the outer diameter of the deflection prism 12, and the inner diameter of the inner lens tube 212 is slightly smaller than the outer diameter of the deflection prism 12. The outer lens tube 211 is longer than the inner lens tube 212, and the height difference between the inner and outer lens tubes forms a step, thereby preliminarily positioning the deflection cemented lens group 1 to be measured.

[0044] The head of the double-layer mirror tube 21 is provided with a plurality of notches, in the form of a claw structure. The electrically-operated clamping jaw 22 is located beside the head of the double-layer mirror tube 21. When the deflection cemented lens group 1 is placed into the double-layer mirror tube 21, the electrically-operated clamping jaw 22 performs a clamping action. The double-layer mirror tube 21 deforms under the action of the electrically-operated clamping jaw 22 due to the notches in the head, indirectly fastening the deflection cemented lens group 1. The claw structure of the double-layer mirror tube 21 is to avoid the electrically-operated clamping jaw 22 directly clamping the deflection cemented lens group 1. The reason is that the electrically-operated clamping jaw 22 has a large size and a large torque, and directly clamping the lens can easily cause the lens to be clamped and cracked.

[0045] The auxiliary support structure 24 is located in the middle and upper part of the double-layer mirror tube 21, providing auxiliary support force to the double-layer mirror tube 21, ensuring the stability of the double-layer mirror tube 21 during testing.

[0046] The tail of the double-layer mirror tube 21 is a mirror tube flange plate 23. The mirror tube flange plate 23 and the flange plate of the light outlet of the integrating sphere uniform light source 3 are connected by bolts, fixing the position.

[0047] The integrating sphere uniform light source 3 provides uniform light for the device. The head of the integrating sphere uniform light source 3 is a light outlet flange plate, which is connected to the flange plate of the lens clamping assembly. The uniform light enters the endoscope tube and converges into a light spot after passing through the deflection cemented lens group 1.

[0048] The camera 5 is located directly above the deflection cemented lens group 1. The camera 5 includes a photosensitive element and an automatic zoom lens.

[0049] The auxiliary rotating table 4 is located below the integrating sphere uniform light source 3 and the lens clamping assembly 2, connected to them, and can rotate 360 degrees, used to ensure that the optical axis of the camera 5 is perpendicular to the top plane of the deflection prism 12.

[0050] The camera 5 can receive light passing through the deflection cemented lens group 1, and through the zoom of the camera 5's own lens, it is visible on the head lens. As shown in Figure 3 , the center of the circular light spot 6 is calculated by image recognition; similarly, the center of the small lens at the top of the deflection cemented lens group is calculated by image recognition. Thus, two points are obtained, and the eccentric distance between them is calculated. Specifically, the small lens group outer contour center 112 is obtained through the small lens group outer contour 111, and the light spot contour center 62 is obtained through the light spot contour 61.

[0051] The method for measuring the eccentric distance of the deflection cemented lens group realized by the device, as shown in Figure 4 , includes the following steps:

[0052] The deflection cemented lens group to be tested is placed in the double-layer mirror tube;

[0053] The electrically-operated clamping jaw clamps and fastens the deflection cemented lens group to be tested in the double-layer mirror tube;

[0054] The integrating sphere uniform light source provides uniform light, and the uniform light converges into a light spot after passing through the deflection cemented lens group to be measured;

[0055] The camera is focused to find the best imaging;

[0056] The auxiliary rotating table is adjusted to make the small lens group have a circular outer contour, i.e., the optical axis of the camera is perpendicular to the top plane of the deflection prism;

[0057] The image recognition light spot contour and the small lens group outer contour are calculated to calculate the distance between the light spot center and the small lens group center, i.e., the eccentric distance of the deflection cemented lens group to be measured.

[0058] In summary, the eccentricity instruments commonly used in the market cannot measure the eccentric distance of the cemented lens group of the non-coaxial type. The automatic recognition device and method for confirming the bonding effect of the deflection prism and the small lens are provided to calculate the eccentric distance of the deflection cemented lens group, thereby providing actual data for subsequent assembly and image performance confirmation. The automatic recognition device has a simple principle and very good actual measurement effect.

[0059] It should be noted that, according to the needs of implementation, each step / component described in the present application can be split into more steps / components, or two or more steps / components or part of the operation of the steps / components can be combined into a new step / component, to achieve the purpose of the present application.

[0060] Those skilled in the art will readily understand that the above is only a preferred embodiment of the present application, and is not intended to limit the present application, and any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. An apparatus for measuring the decentering distance of a deflection gluing mirror group, characterized in that, The device comprises a deflection cemented lens group to be measured, a lens tube clamping assembly, an integrating sphere uniform light source, a camera and an auxiliary rotating table; The deflection cemented lens group to be measured comprises a deflection prism and a small lens group cemented together, resulting in a non-straight optical axis; The lens tube clamping assembly comprises a double-layer lens tube; the inner diameter of the outer lens tube is slightly larger than the outer diameter of the deflection prism, the inner diameter of the inner lens tube is slightly smaller than the outer diameter of the deflection prism, and the outer lens tube is longer than the inner lens tube, so that a step is formed by the height difference between the inner and outer lens tubes to fix the deflection cemented lens group to be measured; The integrating sphere uniform light source is connected with the double-layer lens tube and is used to provide uniform light; the uniform light enters the inner lens tube and converges into a light spot after passing through the deflection cemented lens group to be measured; The camera is located directly above the deflection cemented lens group to be measured; The auxiliary rotating table is connected with the camera or the lens tube clamping assembly and is used to adjust the camera or the lens tube clamping assembly so that the optical axis of the camera is perpendicular to the top plane of the deflection prism; The distance between the center of the light spot and the center of the small lens group is the eccentric distance of the deflection cemented lens group to be measured.

2. The apparatus for determining the decentering distance of a deflection gluing mirror group according to claim 1, characterized in that The lens tube clamping assembly further comprises a clamping jaw; the double-layer lens tube fixed to one end of the deflection cemented lens group to be measured is provided with a plurality of notches and has a claw-shaped structure, which is matched with the clamping jaw; When the deflection cemented lens group to be measured is placed in the double-layer lens tube, the clamping jaw performs a clamping action to fasten the deflection cemented lens group to be measured.

3. The apparatus for determining the decentering distance of a deflection gluing mirror set according to claim 2, characterized in that The clamping jaw is an electric clamping jaw.

4. The apparatus for measuring the decentration of a deflection gluing mirror group according to claim 1, characterized in that, The lens tube clamping assembly further comprises a first flange plate; the first flange plate is located at the light inlet of the double-layer lens tube; The light outlet of the integrating sphere uniform light source is provided with a second flange plate, and the first flange plate and the second flange plate are butt-jointed by bolts.

5. The apparatus for measuring the decentering distance of a deflection gluing mirror set according to claim 1, wherein, The lens tube clamping assembly further comprises an auxiliary support structure; the auxiliary support structure is located at the middle upper part of the double-layer lens tube and provides an auxiliary support force.

6. The apparatus for determining the decentering distance of a deflection gluing mirror set according to claim 5, characterized in that The auxiliary rotating table is connected with the auxiliary support structure to adjust the camera or the lens tube clamping assembly so that the optical axis of the camera is perpendicular to the top plane of the deflection prism.

7. The apparatus for measuring the decentering distance of a deflection gluing mirror set according to claim 1, wherein, The camera comprises a photosensitive element and an automatic zoom lens.

8. A method for determining the eccentricity distance of a deflection gluing mirror group using the device for determining the eccentricity distance of a deflection gluing mirror group according to any one of claims 1 to 7, characterized in that The method comprises the following steps: The deflection cemented lens group to be measured is placed in the double-layer lens tube; The integrating sphere uniform light source provides uniform light, which converges into a light spot after passing through the deflection cemented lens group to be measured; The auxiliary rotating table is adjusted so that the outer contour of the small lens group is circular; The distance between the center of the light spot and the center of the small lens group is calculated, which is the eccentric distance of the deflection cemented lens group to be measured.

9. The method for determining the decentering distance of a deflection gluing mirror group according to claim 8, characterized in that The center of the light spot and the center of the small lens group are identified by image recognition.

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