Optical measurement system for five-dimensional motion change
By designing an optical measurement system that includes XY and Z direction measurement units and angle measurement units, and adopting a dual telecentric optical system, five-dimensional detection of products such as voice coil motors is realized. This solves the problem that existing technologies cannot simultaneously meet the requirement of five-dimensional detection, and improves measurement efficiency and accuracy.
Patent Information
- Application Number
- CN202423041031.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-10
- Publication Date
- 2025-10-28
- Estimated Expiration
- 2034-12-10
AI Technical Summary
Existing optical imaging systems can only perform planar (two-axis) product inspection, and cannot meet the five-dimensional inspection requirements for products such as voice coil motors, including XY-axis pose, Z-axis displacement, and XY-axis tilt.
Design an optical measurement system including an XY direction measurement unit and a Z direction and angle measurement unit. Employ a dual telecentric optical system to achieve five-dimensional parameter measurement through XY direction and Z direction and angle imaging optical components respectively. Utilize an XY direction laser and a Z direction and angle measurement laser to measure the XY direction pose and Z direction displacement and tilt respectively.
It enables simultaneous measurement of five-dimensional parameters during the movement of the object under test, improving measurement efficiency and accuracy, reducing the difficulty of subsequent calibration, and exhibiting low system distortion and high measurement stability.
Smart Images
Figure CN223485110U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of optical imaging technology, and in particular to an optical measurement system for five-dimensional motion changes. Background Technology
[0002] In manufacturing activities, product inspection is a crucial part of the production process. And in industrial inspection, optical inspection systems are among the most important inspection equipment.
[0003] However, current optical imaging systems can only perform planar (two-axis) product inspection, which is insufficient for some high-requirement product inspection processes. For example, when inspecting the quality of a voice coil motor, it is necessary to simultaneously detect the XY orientation, Z displacement, and XY tilt during the motor's movement. Existing imaging equipment cannot meet the detection requirements of five dimensions at the same time, so improvements are needed. Utility Model Content
[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:
[0005] An optical measurement system for five-dimensional motion changes is provided, comprising: an XY direction measurement unit, a Z direction and angle measurement unit.
[0006] The XY direction measurement unit includes an XY direction laser, an XY direction imaging optical component, and an XY direction photodetector. The XY direction photodetector is coaxially arranged with the XY direction imaging optical component and is located on the focal plane of the XY direction imaging optical component. The XY direction laser is located on one side of the XY direction imaging optical component to measure the pose change in the XY direction of the object during its movement. The XY direction imaging optical component includes a first XY direction lens, a second XY direction negative crescent lens, an XY direction beam splitter, an XY direction aperture, a fourth XY direction negative crescent lens, and a fifth XY direction positive crescent lens, arranged sequentially and coaxially.
[0007] The Z-direction and angle measurement unit includes a Z-direction and angle measurement laser, a Z-direction and angle imaging optical component, a Z-direction photodetector, and an angle photodetector. The Z-direction and angle measurement laser and the Z-direction and angle imaging optical component are symmetrically arranged on both sides of the XY-direction imaging optical component to measure the Z-direction displacement and XY-direction tilt during the movement of the object under test. The Z-direction and angle imaging optical component includes a Z-direction first biconvex lens, a Z-direction beam splitter, a Z-direction positive crescent third lens, a Z-direction aperture, a Z-direction negative crescent fourth lens, a Z-direction negative crescent fifth lens, a Z-direction positive crescent sixth lens, and an angle negative crescent lens disposed on the side of the second lens.
[0008] In a preferred embodiment of this utility model, the first lens in the XY direction is a biconvex lens or a meniscus lens.
[0009] In a preferred embodiment of this invention, the XY-direction beam splitter is an aspherical lens.
[0010] In a preferred embodiment of this invention, the parameters of the XY-direction first lens, the XY-direction negative crescent second lens, the XY-direction beam splitter, the XY-direction aperture, the XY-direction negative crescent fourth lens, and the XY-direction positive crescent fifth lens are as follows: .
[0011] In a preferred embodiment of this utility model, the Z-direction first biconvex lens, the Z-direction beam splitter, the Z-direction negative crescent third lens, the Z-direction aperture, the Z-direction positive crescent fourth lens, the Z-direction positive crescent fifth lens, and the Z-direction negative crescent sixth lens constitute a Z-direction imaging optical component, which is used to measure the change of Z-direction displacement during the movement of the object being measured. The Z-direction imaging optical component is coaxially arranged with the Z-direction photodetector.
[0012] In a preferred embodiment of the present invention, the second lens and the negative angle crescent lens form an angle focusing optical component for measuring the angle change during the movement of the object being measured. The Z-direction imaging optical group and the angle focusing optical component share a second lens.
[0013] In a preferred embodiment of this invention, the angle photodetector and the angle focusing optical component are coaxially arranged, or a reflector is arranged between the angle photodetector and the angle negative crescent lens.
[0014] In a preferred embodiment of this utility model, the Z-direction beam splitter is an aspherical lens.
[0015] In a preferred embodiment of this utility model, the parameters of the Z-direction first biconvex lens, the Z-direction beam splitter, the angle negative crescent lens, the Z-direction positive crescent third lens, the Z-direction aperture, the Z-direction negative crescent fourth lens, the Z-direction negative crescent fifth lens, and the Z-direction positive crescent sixth lens are as follows:
[0016] .
[0017] In a preferred embodiment of this utility model, the distance between the XY direction imaging optical component and the object under test is 110mm, and the distance between the Z direction and angle imaging optical component and the object under test is 127.017mm.
[0018] The beneficial effects of this invention are: it can simultaneously measure five dimensions of parameters during the movement of the object under test, including the XY direction pose, Z direction displacement, and XY and Z direction tilt angles, thus improving measurement efficiency. It also effectively improves the accuracy and stability of the measurement, with less system distortion, which greatly reduces the difficulty of subsequent calibration. Attached Figure Description
[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:
[0020] Figure 1 This is a schematic diagram of a preferred embodiment of an optical measurement system for five-dimensional motion changes according to the present invention.
[0021] Figure 2 This is a schematic diagram of the measurement process of a preferred embodiment of an optical measurement system for five-dimensional motion changes according to this utility model;
[0022] Figure 3 This is a schematic diagram of the structure of the XY direction imaging optical component of a preferred embodiment of an optical measurement system for five-dimensional motion changes according to this utility model;
[0023] Figure 4 This is a schematic diagram of the Z-direction and angle imaging optical components of a preferred embodiment of an optical measurement system for five-dimensional motion changes according to this utility model;
[0024] Figure 5 This is a preferred embodiment of an optical measurement system for five-dimensional motion changes according to this utility model, showing the XY direction point array diagram.
[0025] Figure 6 This is an XY direction MTF curve diagram of a preferred embodiment of an optical measurement system for five-dimensional motion changes according to this utility model;
[0026] Figure 7 This is a Z-direction point array diagram of a preferred embodiment of an optical measurement system for five-dimensional motion changes according to this utility model;
[0027] Figure 8 This is a Z-direction MTF curve diagram of a preferred embodiment of an optical measurement system for five-dimensional motion changes according to this utility model;
[0028] Figure 9 This is a Kohler illumination result diagram of a preferred embodiment of an optical measurement system for five-dimensional motion changes according to this utility model;
[0029] Figure 10 This is a cross-sectional view of the Kohler illumination result of a preferred embodiment of an optical measurement system for five-dimensional motion changes according to this utility model. Detailed Implementation
[0030] The technical solutions in the embodiments of this utility model will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0031] Please see Figure 1-10 The embodiments of this utility model include:
[0032] An optical measurement system for five-dimensional motion changes includes an XY direction measurement unit, a Z direction and angle measurement unit, and adopts a dual telecentric optical system to simultaneously detect parameters in five dimensions: XY direction pose, Z direction displacement, and XY and Z direction tilt. This improves measurement accuracy and reduces the difficulty of subsequent calibration.
[0033] Initially, the object to be measured is set to zero. During the movement of the object, the changes in the above five indicators (position / coordinate information) are measured in real time.
[0034] XY direction measurement unit: Vertically set directly above the object being measured, used to measure the pose changes in the XY direction during the movement of the object.
[0035] The XY direction measurement unit includes an XY direction laser 11, an XY direction imaging optical component 12, and an XY direction photodetector 13. The XY direction photodetector and the XY direction imaging optical component are arranged sequentially from top to bottom. The XY direction laser is located on one side of the XY direction imaging optical component, and the XY direction photodetector is located on the focal plane of the XY direction imaging optical component, so as to simultaneously obtain the changes in both XY dimensions.
[0036] The XY-direction imaging optical assembly 12 includes an XY-direction first lens 121, an XY-direction negative crescent second lens 122, an XY-direction beam splitter 123, an XY-direction aperture 124, an XY-direction negative crescent fourth lens 125, and an XY-direction positive crescent fifth lens 126 arranged sequentially and coaxially.
[0037] More preferably, the first lens in the XY direction is a biconvex lens or a meniscus lens.
[0038] Further preferably, the XY-direction beam splitter is an aspherical lens.
[0039] The parameters of the XY direction imaging optical components are shown in the table below. The first surface is the surface of the XY direction negative crescent first lens facing the object being measured, from right to left.
[0040]
[0041] For example, the thickness of the first lens in the XY direction (i.e., the distance between surfaces S1 and S2) is 5.70 mm, the distance between the first lens in the XY direction and the aperture and the second negative crescent lens in the XY direction (i.e., the distance between surfaces S2 and S3) is 1.92 mm, and so on; in addition, the thickness of the XY direction beam splitter is 16.00 mm, and the aperture has no thickness or is 0.5 mm. Therefore, the distance between the XY direction aperture S7 and the XY direction beam splitter S6 is 11.82 mm, the distance between the XY direction aperture S7 and the fourth negative crescent lens S8 in the XY direction is 14.78 mm, and the thickness of the fourth negative crescent lens in the XY direction is 5.99 mm.
[0042] The laser beam emitted from the XY direction laser is incident from the side of the beam splitter prism, passes through the XY direction imaging optics, and is uniformly projected onto the surface of the object under test. The reflected light from the object's surface is then imaged onto the XY direction photodetector by the XY direction imaging optics. As the object under test moves continuously within the measurement range, the laser continues to emit light, and the detector collects data every 2µs, allowing for 500 tests per second.
[0043] Z-direction and angle measurement unit: Located on the side of the XY-direction imaging optical unit, and forming a certain angle with the optical axis of the XY-direction imaging optical unit.
[0044] The Z-direction and angle measurement unit includes a Z-direction and angle measurement laser 21, a Z-direction and angle imaging optical component 22, a Z-direction photodetector 23, and an angle photodetector 24. The Z-direction and angle measurement laser and the Z-direction and angle imaging optical component are symmetrically arranged on both sides of the XY-direction imaging optical component.
[0045] Z-direction and angle imaging optical assembly 22 includes a Z-direction first biconvex lens 221, a Z-direction beam splitter 222, a Z-direction positive crescent third lens 223, a Z-direction aperture 224, a Z-direction negative crescent fourth lens 225, a Z-direction negative crescent fifth lens 226, a Z-direction positive crescent sixth lens 227, and an angle negative crescent lens 228 disposed on the side of the Z-direction second lens.
[0046] In a further preferred embodiment, the Z-direction first biconvex lens, the Z-direction beam splitter, the Z-direction negative crescent third lens, the Z-direction aperture, the Z-direction positive crescent fourth lens, the Z-direction positive crescent fifth lens, and the Z-direction negative crescent sixth lens constitute a Z-direction imaging optical component, which is used to measure the change of Z-direction displacement during the movement of the object being measured. The Z-direction imaging optical component is coaxially arranged with the Z-direction photodetector, and the Z-direction photodetector is located on the focal plane of the Z-direction imaging optical component.
[0047] In a further preferred embodiment, the second lens and the negative angle meniscus lens form an angle-focusing optical assembly, used to measure the angle change during the movement of the object being measured. The angle photodetector is located on the focal plane of the angle-focusing optical assembly. The Z-direction imaging optical group shares a second lens with the angle-focusing optical assembly.
[0048] More preferably, the angle photodetector can be located directly on the image plane of the angle focusing optical component, or a reflector can be set between the angle photodetector and the angle negative crescent lens, depending on the actual size and installation requirements.
[0049] Further preferably, the Z-axis beam splitter is an aspherical lens.
[0050] The parameters of the Z-direction and angle imaging optical components are shown below. The first surface is the surface of the first biconvex lens facing the object being measured, from right to left.
[0051]
[0052] The Z-axis aperture has no thickness or is calculated as 0.5mm.
[0053] The Z-direction and angle measurement unit works similarly to the XY-direction measurement unit. The Z-direction and angle measurement laser emits a collimated small-spot laser beam that illuminates the surface of the object being measured. The reflected light from the object's surface is then imaged onto the Z-direction photodetector and the angle photodetector by the Z-direction and angle imaging optical components. However, because there is an angle between the side surface and the displacement surface, compensation is required during subsequent data processing. Angle measurement is performed using the principle of parallel light focusing.
[0054] The beneficial effects of this utility model's optical measurement system for five-dimensional motion changes are:
[0055] 1. It can simultaneously measure five parameters during the motion of the object under test: XY direction pose, Z direction displacement, and XY and XY direction tilt angles, thus improving measurement efficiency;
[0056] 2. The XY laser forms Kohler illumination after passing through the XY imaging optical component, which generates a uniform illumination spot on the surface of the object being measured. This ensures that the illuminance distribution of the spot is not affected by the laser's output spot, thus solving the problem of changes in the measured value caused by changes in the laser spot energy distribution due to temperature rise. This improves the accuracy and stability of the measurement.
[0057] 3. The XY imaging optical system and the Z-direction imaging optical system adopt a dual telecentric optical path, which ensures that the centroid position of the light spot imaged on the photodetector remains unchanged during the movement of the object under test in the Z direction, thereby improving the measurement accuracy. In addition, the system distortion is small, which reduces the difficulty of subsequent calibration.
[0058] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made using the content of this utility model specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.
Claims
1. An optical measurement system for five-dimensional motion changes, characterized in that, include: XY direction measurement unit, Z direction and angle measurement unit The XY direction measurement unit includes an XY direction laser, an XY direction imaging optical component, and an XY direction photodetector. The XY direction photodetector is coaxially arranged with the XY direction imaging optical component and is located on the focal plane of the XY direction imaging optical component. The XY direction laser is located on one side of the XY direction imaging optical component to measure the pose change in the XY direction of the object during its movement. The XY direction imaging optical component includes a first XY direction lens, a second XY direction negative crescent lens, an XY direction beam splitter, an XY direction aperture, a fourth XY direction negative crescent lens, and a fifth XY direction positive crescent lens, arranged sequentially and coaxially. The Z-direction and angle measurement unit includes a Z-direction and angle measurement laser, a Z-direction and angle imaging optical component, a Z-direction photodetector, and an angle photodetector. The Z-direction and angle measurement laser and the Z-direction and angle imaging optical component are symmetrically arranged on both sides of the XY-direction imaging optical component to measure the Z-direction displacement and XY-direction tilt during the movement of the object under test. The Z-direction and angle imaging optical component includes a Z-direction first biconvex lens, a Z-direction beam splitter, a Z-direction positive crescent third lens, a Z-direction aperture, a Z-direction negative crescent fourth lens, a Z-direction negative crescent fifth lens, a Z-direction positive crescent sixth lens, and an angle negative crescent lens disposed on the side of the second lens.
2. The optical measurement system for five-dimensional motion changes according to claim 1, characterized in that, The first lens in the XY direction is a biconvex lens or a meniscus lens.
3. The optical measurement system for five-dimensional motion changes according to claim 1, characterized in that, The XY-direction beam splitter is an aspherical lens.
4. The optical measurement system for five-dimensional motion changes according to claim 1, characterized in that, The Z-direction first biconvex lens, the Z-direction beam splitter, the Z-direction negative crescent third lens, the Z-direction aperture, the Z-direction positive crescent fourth lens, the Z-direction positive crescent fifth lens, and the Z-direction negative crescent sixth lens constitute a Z-direction imaging optical component, which is used to measure the change of Z-direction displacement during the movement of the object being measured. The Z-direction imaging optical component is coaxially arranged with the Z-direction photodetector.
5. An optical measurement system for five-dimensional motion changes according to claim 1, characterized in that, The second lens and the negative angle crescent lens together form an angle focusing optical assembly, which is used to measure the angle change during the movement of the object being measured. The Z-direction imaging optical group and the angle focusing optical assembly share a second lens.
6. The optical measurement system for five-dimensional motion changes according to claim 1, characterized in that, The angle photodetector and the angle focusing optical assembly are set coaxially, or a reflector is set between the angle photodetector and the angle negative meniscus lens.
7. An optical measurement system for five-dimensional motion changes according to claim 1, characterized in that, The Z-axis beam splitter is an aspherical lens.
8. An optical measurement system for five-dimensional motion changes according to claim 1, characterized in that, The distance between the XY direction imaging optical component and the object being measured is 110 mm, and the distance between the Z direction and angle imaging optical component and the object being measured is 127.017 mm.