Optical testing device and testing equipment
By using a focus component in the optical test device to focus the test optical signal and form a small spot, the problems of divergence of optical fiber and the influence of floating objects are solved, and the reception ability and testing accuracy of the photodetector are improved.
Patent Information
- Application Number
- CN202323497803.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-20
- Publication Date
- 2025-01-17
- Estimated Expiration
- 2033-12-20
AI Technical Summary
When testing the responsiveness of optical devices, existing photodetectors find it difficult to receive all light energy due to the divergent light output from the optical fiber, which affects the test accuracy, and the fiber mode field is small and the environmental floating object covers the measurement inaccurately.
An optical testing device is designed, including a test optical fiber, a focus assembly and a photodetector. The focus assembly focuses the test optical signal to form a small spot far smaller than the photosensitive surface of the photodetector to ensure that the photodetector can receive all signal and reduce the impact of floating objects on the beam.
It improves the accuracy and accuracy of the test, ensures that the photodetector can successfully receive all optical signals, reduces the impact of floating objects on the measurement, and improves the reliability of the responsiveness test.
Smart Images
Figure CN222364737U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of photoelectric detection, in particular to an optical testing device and testing equipment. Background Art
[0002] Responsivity is an important parameter of optical devices, which is used to describe the sensitivity of optical devices to optical signals. When testing the responsivity of optical devices, the intensity of the optical signal in the optical link without the optical device is first measured by a photodetector, and the measured value at this time is used as the initial value and reset to zero. The measured value after the optical device is connected to the optical link is the desired result.
[0003] During the test, the light needs to be output from the optical fiber and projected onto the photosensitive surface of the photodetector. However, the light emitted by the optical fiber is divergent light, which makes it difficult for the photodetector to receive all the light energy, affecting the accuracy of the test. In addition, the mode field diameter of the optical fiber is small. If there are floating objects in the environment and they are randomly covered on the fiber core, it will seriously affect the accuracy of the measurement. Utility Model Content
[0004] The technical problem to be solved by the embodiments of the utility model is to provide an optical testing device and a testing equipment to solve the problem of inaccurate measurement in the prior art.
[0005] The utility model discloses an optical testing device, comprising:
[0006] The optical fiber unit comprises a test optical fiber, wherein the test optical fiber is used to output a test optical signal; the test optical fiber is a single-channel optical fiber or a multi-channel optical fiber;
[0007] A focusing component is located at the light output side of the test optical fiber to focus the test optical signal; the focusing component is a lens or a lens array, and the lens is an aplanatic lens;
[0008] The photoelectric detector is located at the light-emitting side of the focusing assembly and can detect the test light signal.
[0009] Optionally, the end face of the output end of the test optical fiber is a plane or a bevel.
[0010] Optionally, the test light signal can be totally reflected on the inclined surface.
[0011] Optionally, the inclination angle of the slope is greater than or less than 47°.
[0012] Optionally, the test optical fiber can be coupled to the photosensitive surface of the photodetector through the focusing assembly.
[0013] Optionally, the diameter of the light spot formed by the test light signal projected onto the photosensitive surface is smaller than half of the diameter of the photosensitive surface.
[0014] The utility model also discloses a testing device, comprising the optical testing device as described above and a control device connected with the optical testing device.
[0015] Compared with the prior art, the optical test device provided by the embodiment of the utility model has the following beneficial effects: the test optical signal output by the test optical fiber will first be focused by the focusing component to form a light spot much smaller than the photosensitive surface of the photodetector, so that the light spot can be easily aligned with the photosensitive surface, realizing the coupling of the test optical fiber and the photodetector, ensuring that the photodetector can smoothly receive all the test optical signals, thereby improving the accuracy of the test. In addition, the focusing component makes the light beam more concentrated, thereby increasing the energy density output by the test optical fiber, effectively reducing the influence of floating objects on the scattering or absorption of the light beam, and further improving the accuracy of the test. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The technical solution of the utility model will be further described in detail below with reference to the accompanying drawings and embodiments, in which:
[0017] Figure 1 It is a structural schematic diagram of an embodiment of an optical testing device provided by an embodiment of the utility model;
[0018] Figure 2 yes Figure 1 A schematic diagram of a part of the structure when the focusing component 12 is a lens array in an application scenario;
[0019] Figure 3 It is a structural schematic diagram of another embodiment of the lens array provided by the utility model;
[0020] Figure 4 yes Figure 3 A schematic diagram of a part of the structure when the focusing component 12 is a lens array in an application scenario;
[0021] Figure 5 A schematic diagram of the structure of a test device provided in an embodiment of the utility model.
[0022] The reference numerals in the figures are:
[0023] 10. Optical test device; 11. Optical fiber unit; 111. Test optical fiber; 12. Focusing assembly; 13. Photodetector; 131. Photosensitive surface; 20. Test equipment; 21. Control device. DETAILED DESCRIPTION
[0024] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. Now, in conjunction with the accompanying drawings, a preferred embodiment of the present utility model is described in detail.
[0025] In the responsivity test of conventional optical components (such as photodetectors), the direct method is usually used for zeroing. The direct method refers to directly coupling and aligning the light-incoming jumper or optical fiber with the photodetector, and measuring the photocurrent as the initial value. However, there are some problems that need to be solved in this zeroing process.
[0026] The present utility model provides an optical testing device, such as Figure 1 As shown, the optical test device 10 includes an optical fiber unit 11, a focusing assembly 12, and a photodetector 13. The optical fiber unit 11 includes a test optical fiber 111, and the test optical fiber 111 is used to output a test optical signal. The test optical fiber 111 can be a single-mode optical fiber or a multi-mode optical fiber, and can be a single-channel optical fiber or a multi-channel optical fiber. The specific type can be selected according to actual test requirements. In another implementation scenario, the test optical fiber 111 can be a plurality of optical fibers of different types. During actual testing, one of the optical signals can be selected as required, so that one optical test device 10 can be used to meet a variety of different test requirements, effectively reducing the test cost. In addition, different types of optical fiber tests can be achieved by simply switching the test optical fiber 111 of the input optical signal, which effectively improves the test efficiency.
[0027] The focusing component 12 is located at the light-emitting side of the test optical fiber 111, and is used to receive the test optical signal output by the test optical fiber 111, and focus the test optical signal before emitting it. The focusing component 12 can be a lens or a lens array, and one of the main functions of the lens is to focus the light to a specific focus. The lens array can have a larger optical receiving surface than a single lens, so that the distance limit from the light-emitting side of the test optical fiber 111 is wider.
[0028] exist Figure 1 In the illustrated scenario, the output end of the test optical fiber 111 is a plane, so that the test optical signal can be transmitted through the output end of the plane and injected into the focusing component 12. By setting the plane, the flatness of the end face of the test optical fiber 111 can be ensured, thereby reducing the divergence of the light beam. This can increase the coupling efficiency of the optical fiber and reduce the alignment difficulties caused by the small mode field diameter of the optical fiber and the divergence of the light beam.
[0029] The lens can be an aplanatic lens, which corrects spherical distortion and improves the focusing quality of light through its aspherical curvature when focusing light. The radius of curvature of a spherical lens is small in the edge area, resulting in a larger refraction angle of the edge light, thereby generating spherical distortion. The aplanatic lens introduces aspherical curvature on the lens surface to make the refraction of light inside the lens more uniform, thereby improving the focusing effect.
[0030] The lens may also be any one of a spherical lens, a cylindrical lens, a gradient index lens, a biconvex lens, a biconcave lens, a plano-convex lens, and a plano-concave lens.
[0031] The photodetector 13 is located on the light-emitting side of the focusing component 12, and is used to detect the test light signal after focusing. Since the test light signal emitted by the focusing component 12 is concentrated, the light spot emitted to the photosensitive surface 131 of the photodetector 13 is small, so it can be easily coupled with the photosensitive surface 131 of the photodetector 13. In order to improve the coupling success between the light spot and the photosensitive surface 131, the diameter of the light spot is less than half the diameter of the photosensitive surface 131. The small diameter light spot is easier to align with the center of the photosensitive surface 131 because the smaller light spot diameter reduces the alignment error range. This can improve the coupling success between the light spot and the photosensitive surface 131 and improve the accuracy and reliability of the test.
[0032] See also Figure 2 , Figure 2 yes Figure 1 A partial structural diagram of an optical test device when the focusing component 12 is a lens array in an application scenario. When the test optical fiber 111 is a single optical fiber, the focusing component 12 is a lens. When the number of test optical fibers 111 is multiple, the focusing component 12 is a lens array, and each lens corresponds to a test optical fiber 111. Correspondingly, the number of photodetectors 13 is also multiple to correspond to each lens. Figure 2 In the scene shown, the test optical signal is transmitted from the planar output end of each test optical fiber 111 , and is focused by each lens and then emitted to each photodetector 13 .
[0033] In addition, adding a focusing assembly 12 to the output end of the test optical fiber 111 for focusing can solve the problem of small optical fiber mode field diameter and floating objects in the environment. The focusing effect of the focusing assembly 12 can focus the light beam from the small mode field diameter of the test optical fiber 111 to a smaller point, so that even if there are floating objects covering the test optical fiber 111, their impact will be reduced.
[0034] The focusing function of the focusing assembly 12 can make the light beam more concentrated, thereby increasing the energy density of the optical fiber output. In this way, even if there are some floating objects covering the optical fiber, their scattering or absorption of the light beam will be weakened. Therefore, the use of the focusing assembly 12 can reduce the influence of floating objects in the environment on the initial measurement value.
[0035] In one implementation scenario, when the focusing component 12 is an aplanatic lens, the light spot can be reduced to less than 5 μm. The diameter of the photosensitive surface 131 of a general photodetector 13 is 16 μm, and the diameter of the light spot is much smaller than the diameter of the photosensitive surface 131. In this way, the light spot can be easily aligned and coupled with the photosensitive surface 131, and the photodetector can receive all the light energy.
[0036] See also Figure 3 , Figure 3 It is a structural schematic diagram of another embodiment of the lens array provided by the utility model. The output end face of the test optical fiber 111 is an inclined surface, so that when the light hits the inclined surface, it will be reflected. In order to ensure the reliability of the test, the inclination angle of the inclined surface can be adjusted to ensure that the light can be fully reflected on the inclined surface. For example, when the inclination angle of the inclined surface is less than 47°, it can be ensured that the light can be fully reflected on the inclined surface.
[0037] The light is reflected at the inclined surface, and the propagation direction of the light can be changed, making it more suitable for coupling with other optical elements (such as focusing assembly 12). In this way, the path and focus position of the light can be better controlled. The inclined surface can be used to adjust the position and layout of the optical elements to meet the space limitations of the system or optimize the optical path design.
[0038] By setting the inclined surface, the flatness of the end face of the test optical fiber 111 can be ensured, thereby reducing the divergence of the light beam. This can increase the coupling efficiency of the optical fiber and reduce the difficulty of alignment caused by the small optical fiber mode field diameter and the divergence of the light beam. In addition, total reflection can also reduce the sensitivity of the optical fiber end face, reducing its impact on the fluctuations and vibrations of the surrounding environment.
[0039] See also Figure 4 , Figure 4 The present invention provides Figure 3 A partial structural diagram of the focusing component 12 when it is a lens array in the application scenario.
[0040] It can be seen from the above description that in this embodiment, the test optical signal output by the test optical fiber will first be focused by the focusing component to form a light spot that is much smaller than the photosensitive surface of the photodetector, so that the light spot can be easily aligned with the photosensitive surface to achieve the coupling of the test optical fiber and the photodetector, ensuring that the photodetector can smoothly receive all the test optical signals, thereby improving the accuracy of the test. In addition, the focusing component makes the light beam more concentrated, thereby increasing the energy density output by the test optical fiber, effectively reducing the influence of floating objects on the scattering or absorption of the light beam, and further improving the accuracy of the test.
[0041] See also Figure 5 , Figure 5 The test device 20 includes a control device 21 and an optical test device 10, wherein the control device 21 is used to control the optical test device 10 to detect the photodetector 13, receive the electrical signal output by the photodetector 13, and obtain the responsivity based on the electrical signal.
[0042] Specifically, without adding the optical device to be tested to the optical link, the light source is driven to emit a test light signal, which is transmitted through the test optical fiber 111. When it reaches the end face, since the end face of the test optical fiber 111 is a bevel, the test light signal is totally reflected on the bevel and emitted to the focusing component 12. The focusing component 12 focuses the test light signal and transmits the focused test light signal to the photodetector 13. Since the test light signal is focused, a very small light spot can be formed on the photosensitive surface 131 of the photodetector 13. The light spot is much smaller than the size of the photosensitive surface 131, so it can be easily aligned on the photosensitive surface 131, thereby achieving that the test optical fiber 111 can be easily coupled and aligned with the photosensitive surface 131. The photodetector 13 can accurately receive all the test light signals, and the value measured at this time is used as the initial value and is set to zero.
[0043] Then, the optical device to be tested is added to the optical link, and the light source is driven to emit a test optical signal. The test optical signal will pass through the optical device, and then be transmitted through the test optical fiber 111, and then be focused by the focusing component 12 and emitted to the photodetector 13. The photodetector 13 then outputs a test value according to the optical signal received at this time. Since the measured value is set to zero before, the test value at this time is the difference between the initial value and the subsequent value. The responsiveness of the optical device can be obtained based on the test value.
[0044] Since the test light signal will first be focused by the focusing component to form a light spot that is much smaller than the photosensitive surface of the photodetector, it is easy to align the light spot with the photosensitive surface to achieve the coupling of the test optical fiber and the photodetector, ensuring that the photodetector can successfully receive all the test light signals, thereby ensuring the accuracy of the test responsiveness.
[0045] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present utility model rather than to limit it. For those skilled in the art, the technical solutions described in the above embodiments can be modified, or some of the technical features therein can be replaced by equivalents; and all these modifications and replacements should fall within the scope of protection of the claims attached to the present utility model.
Claims
1. An optical testing device, characterized in that: include: An optical fiber unit, comprising a test optical fiber, wherein the test optical fiber is used to output a test optical signal; The test optical fiber is a single-channel optical fiber or a multi-channel optical fiber; A focusing component, located at the light output side of the test optical fiber, to focus the test optical signal; The focusing component is a lens or a lens array, and the lens is an aplanatic lens; The photoelectric detector is located at the light-emitting side of the focusing assembly and can detect the test light signal.
2. The optical testing device according to claim 1, characterized in that: The end face of the output end of the test optical fiber is a plane or an inclined plane.
3. The optical testing device according to claim 2, characterized in that: The test light signal can be totally reflected on the inclined surface.
4. The optical testing device according to claim 3, characterized in that: The inclination angle of the inclined surface is less than 47°.
5. The optical testing device according to claim 1, characterized in that: The testing optical fiber can be coupled to the photosensitive surface of the photodetector through the focusing assembly.
6. The optical testing device according to claim 5, characterized in that: The diameter of the light spot formed by the test light signal projected onto the photosensitive surface is smaller than half of the diameter of the photosensitive surface.
7. A testing device, characterized in that: The optical testing device comprises the optical testing device according to any one of claims 1 to 6 and a control device connected to the optical testing device.