Device for measuring parameters of optical lens
By integrating optical lens parameter measurement devices with modules such as fiber optic modules, the problems of cumbersome operation and limited accuracy in optical lens measurement methods have been solved, enabling rapid and accurate multi-parameter measurement.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-24
- Publication Date
- 2026-03-06
AI Technical Summary
Existing optical lens measurement methods are cumbersome to operate and have limited measurement accuracy, making them unsuitable for large-scale production testing.
An optical lens parameter measurement device was designed, integrating an optical fiber module, a delay line module, a detection module, a light source module, a camera module, and an adjustment coaxial module. By combining low-coherence and high-coherence light, it achieves accurate measurement of multiple parameters.
It simplifies equipment installation and debugging, improves ranging speed, enables accurate measurement of multiple parameters, and reduces the complexity of the interferometer.
Smart Images
Figure CN223976830U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of lens parameter measurement technology, and in particular to a device for measuring optical lens parameters. Background Technology
[0002] In the design, manufacturing, and testing of optical lenses, accurate measurement of the lens's geometric parameters is crucial for ensuring optical performance. In particular, the lens's center deviation and focal length are two key parameters that directly affect the lens's image quality and the overall performance of the optical system. The center deviation of an optical lens refers to the degree of deviation between the lens's optical center and its geometric center, while the focal length determines the imaging distance and sharpness of the optical system.
[0003] Currently, traditional optical lens measurement methods typically rely on mechanical alignment and optical imaging techniques, such as using precision optical stages, interferometers, or image processing technologies. However, these methods generally suffer from problems such as cumbersome operation, limited measurement accuracy, or inability to adapt to large-scale production testing. Utility Model Content
[0004] To solve the above-mentioned technical problems, the purpose of this utility model is to provide a measuring device for optical lens parameters, which can reduce the complexity of interferometers and improve the speed of distance measurement, and realize the accurate measurement of multiple parameters.
[0005] The technical solution adopted by this utility model is:
[0006] An optical lens parameter measuring device includes an optical fiber module, a delay line module, a detection module, a light source module, a camera module, and an adjustment coaxial module. The first output terminal of the optical fiber module is connected to the input terminal of the adjustment coaxial module; the second output terminal of the optical fiber module is connected to the input terminal of the delay line module; the third output terminal of the optical fiber module is connected to the input terminal of the detection module; the first output terminal of the adjustment coaxial module is connected to the input terminal of the light source module; and the second output terminal of the adjustment coaxial module is connected to the input terminal of the camera module.
[0007] Furthermore, the fiber optic module includes a broadband light source, a narrowband light source, a first coupler, a second coupler, a wavelength division multiplexer, and an end-face mirror. The output of the broadband light source is connected to the input of the first coupler, the output of the narrowband light source is connected to the input of the second coupler, the first output of the first coupler is connected to the first input of the wavelength division multiplexer, the first output of the second coupler is connected to the second input of the wavelength division multiplexer, and the second output of the second coupler is connected to the input of the end-face mirror.
[0008] Furthermore, the delay line module includes a first collimator, a right-angle prism, and a first reflector, wherein the output of the wavelength division multiplexer is connected to the input of the first collimator, the output of the first collimator is connected to the input of the right-angle prism, and the output of the right-angle prism is connected to the input of the first reflector.
[0009] Furthermore, the detection module includes a first photodetector, a second photodetector, and a terminal device. The second output terminal of the first coupler is connected to the output terminal of the first photodetector, the third output terminal of the second coupler is connected to the input terminal of the second photodetector, the output terminal of the first photodetector is connected to the first input terminal of the terminal device, and the output terminal of the second photodetector is connected to the second input terminal of the terminal device.
[0010] Furthermore, the coaxial adjustment module includes a second collimator, a first beam splitter, a second beam splitter, and a second reflector. The third output terminal of the first coupler is connected to the input terminal of the second collimator; the output terminal of the second collimator is connected to the input terminal of the first beam splitter; the first output terminal of the first beam splitter is connected to the first input terminal of the light source module; the second output terminal of the first beam splitter is connected to the input terminal of the second beam splitter; the first output terminal of the second beam splitter is connected to the input terminal of the second reflector; the second output terminal of the second beam splitter is connected to the second input terminal of the light source module; and the third output terminal of the second beam splitter is connected to the input terminal of the camera module.
[0011] Furthermore, the light source module includes a first white light source, a second white light source, a first cross-shaped target ring, a second cross-shaped target ring, a sample lens, and a first convex lens. The output end of the first white light source is connected to the input end of the first cross-shaped target ring, the output end of the second white light source is connected to the input end of the second cross-shaped target ring, the output end of the first cross-shaped target ring is connected to the input end of the first convex lens, the output end of the second cross-shaped target ring is connected to the input end of the sample lens, the first convex lens is connected to the first beam splitter, and the sample lens is connected to the second beam splitter.
[0012] Furthermore, the light source module also includes a second convex lens, a linear stepper motor, and a rotary integrated frame, wherein the second convex lens is located between the sample lens and the second beam splitter, the rotary integrated frame is fixedly connected to the sample lens, and the linear stepper motor is electrically connected to the second convex lens.
[0013] Furthermore, the camera module includes a third convex lens and a CCD camera, wherein the third convex lens is connected to the second beam splitter, and the output end of the third convex lens is connected to the input end of the CCD camera.
[0014] The beneficial effects of this utility model are as follows: By integrating the measurement of multiple parameters such as radius of curvature, focal length, and center deviation into a single coaxial optical path, this utility model simplifies the structure, reduces the complexity of equipment installation and debugging, enables rapid distance measurement, facilitates coaxial adjustment of the optical path before measurement, reduces the complexity of the interferometer, increases the speed of distance measurement, and enables accurate measurement of multiple parameters. Attached Figure Description
[0015] Figure 1 This is a diagram of the device of this utility model;
[0016] Figure 2 This is a schematic diagram of the optical path for measuring the radius of curvature and center deviation according to this utility model;
[0017] Figure 3 This is a schematic diagram of the optical path for measuring the effective focal length and back focal length according to this utility model;
[0018] Reference numerals: 1. Fiber optic module; 2. Delay line module; 3. Detection module; 4. Light source module; 5. Camera module; 6. Adjustment coaxial module; 7. Broadband light source; 8. Narrowband light source; 9. First coupler; 10. Second coupler; 11. Wavelength division multiplexer; 12. End face mirror; 13. First collimator; 14. First mirror; 15. Right angle prism; 16. First photodetector; 17. Second photodetector; 18. Terminal equipment; 19. First convex lens; 20. First cross-shaped target ring; 21. First white light source; 22. Second white light source; 23. Second cross-shaped target ring; 24. Sample lens; 25. Third convex lens; 26. CCD camera; 27. Second collimator; 28. First beam splitter; 29. Second beam splitter; 30. Second mirror; 31. Rotary integrated frame; 32. Second convex lens; 33. Stepper motor. Detailed Implementation
[0019] like Figure 1As shown, this utility model provides a device for measuring optical lens parameters, including an optical fiber module 1, a delay line module 2, a detection module 3, a light source module 4, a camera module 5, and an adjustment coaxial module 6. The first output terminal of the optical fiber module 1 is connected to the input terminal of the adjustment coaxial module 6, the second output terminal of the optical fiber module 1 is connected to the input terminal of the delay line module 2, the third output terminal of the optical fiber module 1 is connected to the input terminal of the detection module 3, the first output terminal of the adjustment coaxial module 6 is connected to the input terminal of the light source module 4, and the second output terminal of the adjustment coaxial module 6 is connected to the input terminal of the camera module 5.
[0020] The fiber optic module 1 includes a broadband light source 7, a narrowband light source 8, a first coupler 9, a second coupler 10, a wavelength division multiplexer 11, and an end-face reflector 12. The output of the broadband light source 7 is connected to the input of the first coupler 9, the output of the narrowband light source 8 is connected to the input of the second coupler 10, the first output of the first coupler 9 is connected to the first input of the wavelength division multiplexer 11, the first output of the second coupler 10 is connected to the second input of the wavelength division multiplexer 11, and the second output of the second coupler 10 is connected to the input of the end-face reflector 12.
[0021] As a further preferred embodiment, the broadband light source 7 is a 1310nm light source used to emit broadband light with a center wavelength of 1310nm, the narrowband light source 8 is a 1550nm light source used to emit narrowband light with a center wavelength of 1550nm, the first coupler 9 is a 3×3 coupler used to split the incident light into three beams of equal intensity, the second coupler 10 is a 2×2 coupler used to split the incident light into two beams of equal intensity, the wavelength division multiplexer 11 is used to couple the 1310nm light and the 1550nm light, and the end face reflector 12 is used to reflect the beam.
[0022] The delay line module 2 includes a first collimator 13, a right-angle prism 15, and a first reflector 14. The output of the wavelength division multiplexer 11 is connected to the input of the first collimator 13, the output of the first collimator 13 is connected to the input of the right-angle prism 15, and the output of the right-angle prism 15 is connected to the input of the first reflector 14.
[0023] As a further preferred embodiment, the first collimator 13 is used to emit parallel light, the right-angle prism 15 is used for optical path scanning, and the first reflector 14 is used to reflect the light beam.
[0024] The detection module 3 includes a first photodetector 16, a second photodetector 17, and a terminal device 18. The second output terminal of the first coupler 9 is connected to the output terminal of the first photodetector 16, the third output terminal of the second coupler 10 is connected to the input terminal of the second photodetector 17, the output terminal of the first photodetector 16 is connected to the first input terminal of the terminal device 18, and the output terminal of the second photodetector 17 is connected to the second input terminal of the terminal device 18.
[0025] As a further preferred embodiment, the first photodetector 16 and the second photodetector 17 are used to receive optical signals, and the terminal device 18 can be a computer, mobile phone, etc., used for optical signal data processing and display.
[0026] The coaxial adjustment module 6 includes a second collimator 27, a first beam splitter 28, a second beam splitter 29, and a second reflector 30. The third output of the first coupler 9 is connected to the input of the second collimator 27, the output of the second collimator 27 is connected to the input of the first beam splitter 28, the first output of the first beam splitter 28 is connected to the first input of the light source module 4, the second output of the first beam splitter 28 is connected to the input of the second beam splitter 29, the first output of the second beam splitter 29 is connected to the input of the second reflector 30, the second output of the second beam splitter 29 is connected to the second input of the light source module 4, and the third output of the second beam splitter 29 is connected to the input of the camera module 5.
[0027] As a further preferred embodiment, the second collimator 27 is used to emit parallel light, the first beam splitter 28 and the second beam splitter 29 are used to split the beam, one beam is transmitted and the other is reflected, and the second reflector 30 is used to reflect the beam.
[0028] The light source module 4 includes a first white light source 21, a second white light source 22, a first cross-shaped target ring 20, a second cross-shaped target ring 23, a sample lens 24, and a first convex lens 19. The output end of the first white light source 21 is connected to the input end of the first cross-shaped target ring 20, the output end of the second white light source 22 is connected to the input end of the second cross-shaped target ring 23, the output end of the first cross-shaped target ring 20 is connected to the input end of the first convex lens 19, the output end of the second cross-shaped target ring 23 is connected to the input end of the sample lens 24, the first convex lens 19 is connected to the first beam splitter 28, and the sample lens 24 is connected to the second beam splitter 29.
[0029] As a further preferred embodiment, the first white light source 21 and the second white light source 22 are used to emit stray white light to measure the radius of curvature, center deviation, effective focal length and back focal length. The first cross target ring 20 and the second cross target ring 23 are used to convert stray light into cross light. The sample lens 24 is used to generate interference peak signal of the sample to be tested. The first convex lens 19 is used to convert cross light into parallel light.
[0030] The light source module 4 further includes a second convex lens 32, a linear stepper motor 33, and a rotating integrated frame 31. The second convex lens 32 is located between the sample lens 24 and the second beam splitter 29. The rotating integrated frame 31 is fixedly connected to the sample lens 24, and the linear stepper motor 33 is electrically connected to the second convex lens 32.
[0031] As a further preferred embodiment, the second convex lens 32 is used to focus parallel light onto the sample, the linear motor 33 is used to drive the second convex lens 32 to move back and forth linearly, and the rotating integrated frame 31 is used to make the sample rotate.
[0032] The camera module 5 includes a third convex lens 25 and a CCD camera 26. The third convex lens 25 is connected to the second beam splitter 29, and the output end of the third convex lens 25 is connected to the input end of the CCD camera 26.
[0033] As a further preferred embodiment, the third convex lens 25 is used to focus parallel light onto the camera, and the CCD camera 26 is used to receive the sample backlight image.
[0034] The specific embodiments of this utility model are as follows:
[0035] An optical lens parameter measuring device includes a broadband light source 7, a narrowband light source 8, a first coupler 9, a second coupler 10, a wavelength division multiplexer 11, an end face mirror 12, a first collimator 13, a right-angle prism 15, a first reflector 14, a first photodetector 16, a second photodetector 17, a terminal device 18, a second collimator 27, a first beam splitter prism 28, a second beam splitter prism 29, a second reflector 30, a first white light source 21, a second white light source 22, a first cross-shaped target ring 20, a second cross-shaped target ring 23, a sample lens 24, a first convex lens 19, a second convex lens 32, a linear stepper motor 33, a rotating integrated frame 31, a third convex lens 25, and a CCD camera 26, etc.
[0036] The working principle is as follows:
[0037] First, distance measurement is performed, and the interferometer is adjusted to achieve a coaxial state. Based on the Michelson interferometer structure, light emitted from the broadband light source 7 is split by the first coupler 9 via optical fiber. One beam enters the measurement optical path to extract the interference peak signal of the sample under test. Simultaneously, light emitted from the narrowband light source 8 is split by the second coupler 10. One beam is reflected back to the second coupler 10 by the end face mirror 12, while the other beam, along with the beam from the first coupler 9, enters the wavelength division multiplexer 11 and exits through the first collimator 13, striking the right-angle prism 15. The light, after being refracted by the prism and hitting the first reflecting mirror 14, returns along the same path. It forms an interference peak with the light returning from the measurement optical path at the first coupler 9, and forms a scale light with the light returning from the end face reflecting mirror 12 at the second coupler 10. The interference peak signal and the scale light are received by the first photodetector 16 and the second photodetector 17 and transmitted to the terminal device 18 for signal processing. The right-angle prism 15 is a rotating optical delay line, mainly used for the rapid optical path scanning of the measurement module to form multiple interference peaks, and for accurate distance measurement using the scale light system.
[0038] The light emitted from the first coupler 9 serves two purposes: ranging and coaxial adjustment of the entire measurement optical path. Specifically, the light emitted from the second collimator 27 passes sequentially through the first beam splitter 28 and the second beam splitter 29. In the second beam splitter 29, the light is split into two beams. One beam is transmitted through the second reflecting mirror 30 and returns along the same path. It is then reflected by the second beam splitter 29, passes through the third convex lens 25 and the CCD camera 26, and is reflected by the first beam splitter 28, passing through the first convex lens 19 and the first crosshair target ring 20. The other beam is reflected sequentially through the second convex lens 32, the sample lens 24, and the second crosshair target ring 23. Finally, the data from the terminal device 18 determines the coaxial adjustment status.
[0039] Furthermore, such as Figure 2 As shown, to measure the radius of curvature and center deviation of the lens, the first white light source 21 emits stray light, which is transformed into a cross beam by the first cross target ring 20. This cross beam then passes through the first convex lens 19 to form parallel light, which sequentially passes through the first beam splitter 28, the second beam splitter 29, and the second convex lens 32. A linear stepper motor 33 sequentially focuses the light onto the front surface and center of the sample lens 24. After reflection, the light returns through the second beam splitter 29, passing through the third convex lens 25 and focusing onto the CCD camera 26, forming two clearest cross images. The other path returns to the fiber optic ranging system, forming an interference peak. Simultaneously, the light from the rear surface of the second convex lens 32 also returns to the fiber optic ranging system, forming an interference peak. The distance between these two interference peaks is measured and marked as x. a and x b Then the radius of curvature R is:
[0040] R = |x a -x b |
[0041] In the above formula, R represents the radius of curvature, x a x b This indicates the distance between the two sets of interference peaks.
[0042] When the light beam hits the surface of the sample lens 24, the rotating integrated frame 31 drives the sample to rotate. At this time, the motion trajectory of the reflected cross image can be monitored in the CCD camera 26. We fit the four straight lines of the cross image to obtain the center and draw the trajectory diagram. We find that it is roughly circular. We fit it into a trajectory circle. The radius of the circle reflects the center deviation of the lens being measured.
[0043] Finally, as Figure 3 As shown, to measure the effective focal length and back focal length of the lens, the second convex lens 32 and the linear stepper motor 33 are first moved off-axis via parallel guide rails. Stray light emitted from the second white light source 22 is amplified into a cross beam by the second cross target ring 23, and then focused onto the CCD camera 26 by the sample lens 24, the second beam splitter prism 29, and the third convex lens 25. We know the original height of the cross target ring is y and the focal length of the third convex lens 25 is f. c If the height of the crosshair image is obtained as y', then the focal length f' of the sample lens 24 is:
[0044]
[0045] In the above formula, f' represents the 24-focal length of the sample lens.
[0046] The specific process for measuring the back focal length of a lens is as follows: Light from the fiber optic ranging system exits through the second collimator 27, passes sequentially through the first beam splitter 28 and the second beam splitter 29, and strikes the rear surface of the sample lens 24 and the second crosshair target ring 23, respectively. The reflected light and the reflected light from the optical delay line scan at the same optical path point generate interference peaks at the first coupler 9. Since the second crosshair target ring 23 is located at the focal point of the sample lens 24, the distance between the interference peak of the crosshair target ring and the interference peak on the rear surface of the sample lens 24 is the back focal length. The distance between the two interference peaks can be measured using a scale optical system to obtain the back focal length.
[0047] In summary, the present invention has the following advantages over the prior art:
[0048] 1) Integrate the measurement of multiple parameters such as radius of curvature, focal length, and center deviation into a single coaxial optical path.
[0049] 2) The fiber optic ranging system uses a combination of low-coherence and high-coherence optical systems to achieve rapid ranging.
[0050] 3) Another function of the fiber optic ranging system is to adjust the overall optical path coaxiality.
[0051] 4) Measurements using stray light are simple in terms of light source requirements and other conditions.
[0052] The above is a detailed description of the preferred embodiments of the present utility model. However, the present utility model is not limited to the described embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present utility model. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.
Claims
1. A device for measuring parameters of an optical lens, characterized in that: The application relates to a fiber module, a delay line module, a detection module, a light source module, a camera module and an adjusting coaxial module, wherein the first output end of the fiber module is connected with the input end of the adjusting coaxial module, the second output end of the fiber module is connected with the input end of the delay line module, the third output end of the fiber module is connected with the input end of the detection module, the first output end of the adjusting coaxial module is connected with the input end of the light source module, and the second output end of the adjusting coaxial module is connected with the input end of the camera module.
2. A device for measuring parameters of an optical lens according to claim 1, characterized in that: The fiber module comprises a broadband light source, a narrowband light source, a first coupler, a second coupler, a wavelength division multiplexer and an end face mirror, wherein the output end of the broadband light source is connected with the input end of the first coupler, the output end of the narrowband light source is connected with the input end of the second coupler, the first output end of the first coupler is connected with the first input end of the wavelength division multiplexer, the first output end of the second coupler is connected with the second input end of the wavelength division multiplexer, and the second output end of the second coupler is connected with the input end of the end face mirror.
3. A device for measuring parameters of an optical lens according to claim 2, characterized in that: The delay line module comprises a first collimator, a right-angle prism and a first mirror, wherein the output end of the wavelength division multiplexer is connected with the input end of the first collimator, the output end of the first collimator is connected with the input end of the right-angle prism, and the output end of the right-angle prism is connected with the input end of the first mirror.
4. A device for measuring parameters of an optical lens according to claim 3, characterized in that: The detection module comprises a first photodetector, a second photodetector and a terminal device, the second output end of the first coupler is connected with the output end of the first photodetector, the third output end of the second coupler is connected with the input end of the second photodetector, the output end of the first photodetector is connected with the first input end of the terminal device, and the output end of the second photodetector is connected with the second input end of the terminal device.
5. A device for measuring parameters of an optical lens according to claim 4, characterized in that: The adjusting coaxial module comprises a second collimator, a first light splitting prism, a second light splitting prism and a second mirror, wherein the third output end of the first coupler is connected with the input end of the second collimator, the output end of the second collimator is connected with the input end of the first light splitting prism, the first output end of the first light splitting prism is connected with the first input end of the light source module, the second output end of the first light splitting prism is connected with the input end of the second light splitting prism, the first output end of the second light splitting prism is connected with the input end of the second mirror, the second output end of the second light splitting prism is connected with the second input end of the light source module, and the third output end of the second light splitting prism is connected with the input end of the camera module.
6. A device for measuring parameters of an optical lens according to claim 5, characterized in that: The light source module comprises a first white light source, a second white light source, a first cross target ring, a second cross target ring, a sample lens and a first convex lens, wherein the output end of the first white light source is connected with the input end of the first cross target ring, the output end of the second white light source is connected with the input end of the second cross target ring, the output end of the first cross target ring is connected with the input end of the first convex lens, the output end of the second cross target ring is connected with the input end of the sample lens, the first convex lens is connected with the first beam-splitting prism, and the sample lens is connected with the second beam-splitting prism.
7. A device for measuring parameters of an optical lens according to claim 6, characterized in that: The light source module further comprises a second convex lens, a straight step motor and a rotating integrated frame, wherein the second convex lens is between the sample lens and the second beam-splitting prism, the rotating integrated frame is fixedly connected with the sample lens, and the straight step motor is electrically connected with the second convex lens.
8. A device for measuring parameters of an optical lens according to claim 7, characterized in that: The camera module comprises a third convex lens and a CCD camera, wherein the third convex lens is connected with the second beam-splitting prism, and the output end of the third convex lens is connected with the input end of the CCD camera.