Multifunctional device capable of testing optical performance of super lens

Abstract

The invention relates to a multifunctional device capable of testing the optical performance of a super lens, which belongs to the technical field of testing devices and comprises a first light source module, a diaphragm module, a sample operating table, a microscopic light path system and a computer control and display system, the first light source module is composed of a single-mode laser light source and an optical fiber collimator. The diaphragm module comprises a fixed aperture diaphragm and a sample aperture diaphragm, the sample aperture diaphragm is subjected to three-dimensional adjustment through the sample operation table, and the sample aperture diaphragm can switch different apertures so as to adapt to lenses with different designs. And the method has good universality.

Description

Technical Field

[0001] The present invention belongs to the field of testing devices, and particularly relates to a multifunctional device capable of realizing the optical performance testing of a metasurface lens. Background Art

[0002] In recent years, fields such as smart phones, AR / VR, and robots have been developing rapidly. Near-infrared optical systems play an increasingly important role in these intelligent fields. With the continuous progress of technology, the application prospects of near-infrared optical systems will be even broader. As one of the key components, the metasurface lens plays a crucial role in the performance of near-infrared optical systems. In traditional designs based on refractive lenses, it is difficult to make the size of the lens small, which cannot meet the development trend of miniaturization and lightweight. The metasurface lens can use semiconductor lithography technology on silicon or glass wafers to achieve large-scale sub-wavelength-scale device design, greatly reducing the size of the lens and improving various parameters of the lens. To ensure that the performance and quality of the metasurface lens meet the requirements, comprehensive performance evaluation and testing are needed. After the semiconductor etching process of the metasurface lens is completed, in addition to appearance inspection, optical performance testing needs to be carried out. Among them, transmittance, focal length, modulation transfer function, field of view angle, distortion, and relative illuminance are important optical performance parameters.

[0003] Currently, the functions of the devices for detecting the optical performance of metasurface lenses on the market are relatively single, mainly using multiple detection devices to evaluate different optical performances. The metasurface lens detection system of Fuxiang Optics, which combines microscopic imaging technology, off-axis digital holography technology, and far-field imaging technology, can measure the focal length, phase distribution, and modulation transfer function. However, its preparation cost is high, the functions are relatively few, and the flexibility is low. Therefore, proposing a multifunctional device and method with low preparation cost, rich functions, and capable of freely adjusting optical path components to realize the optical performance testing of metasurface lenses will be of great help to the measurement and analysis of near-infrared metasurface lenses and has broad application prospects in optical performance detection. Summary of the Invention

[0004] The present application provides a multifunctional device capable of realizing the optical performance testing of a metasurface lens to at least solve the above technical problems existing in the prior art.

[0005] An embodiment of the present application provides a multifunctional device capable of realizing the optical performance testing of a metasurface lens, including a first light source module, a diaphragm module, a sample operation table, a microscopic optical path system, and a computer control and display system;

[0006] The first light source module is composed of a single-mode laser light source and a fiber collimator;

[0007] The diaphragm module includes a fixed-aperture diaphragm and a sample-aperture diaphragm. The sample-aperture diaphragm is adjusted three-dimensionally through the sample operating table, and the sample-aperture diaphragm can switch different apertures to adapt to lenses of different designs.

[0008] In an implementable embodiment, the sample operating table includes an optical carrier table and a sample displacement table. The optical carrier table is used for placing a sample; the optical carrier table is adjusted three-dimensionally along with the sample displacement table.

[0009] In an implementable embodiment, the sample operating table further includes a diaphragm displacement table, and the diaphragm displacement table is used for three-dimensional adjustment of the diaphragm module to make the diaphragm module coaxial with the sample.

[0010] In an implementable embodiment, the microscopic optical path system includes a microscopic objective lens, a tube lens, and a area array camera. The tube lens and the microscopic objective lens are detachably connected; one end of the tube lens is connected to the microscopic objective lens, and the other end of the tube lens is connected to the area array camera.

[0011] In an implementable embodiment, an optical performance detection component is further included. The optical performance detection component includes a power meter, and the power meter is arranged behind the optical carrier table.

[0012] In an implementable embodiment, the first light source module is replaced with a second light source module, and the second light source module includes an area array light source and a test chart.

[0013] In an implementable embodiment, a beam splitting prism is arranged behind the fixed-aperture diaphragm.

[0014] In an implementable embodiment, a beam splitting prism is arranged in front of the microscopic objective lens.

[0015] In an implementable embodiment, a beam splitting prism is arranged behind the tube lens. Description of the Drawings

[0016] Figure 1 is a schematic structural diagram of the multifunctional device in an embodiment of the present application;

[0017] Figure 2 is a schematic structural diagram of the multifunctional device that can quickly measure different samples in an embodiment of the present application;

[0018] Figure 3 is a schematic structural diagram of the multifunctional device that simultaneously measures the back focal length and transmittance in an embodiment of the present application;

[0019] Figure 4 is a schematic structural diagram of the multifunctional device when the first light source module is replaced with the second light source module in an embodiment of the present application;

[0020] Figure 5It is a schematic structural diagram of a multifunctional device for measuring imaging quality at different wavelengths in an embodiment of the present application;

[0021] Explanation of reference numerals:

[0022] 1. First light source module; 2. Fixed aperture diaphragm; 3. Sample aperture diaphragm; 4. Optical carrier table; 5. Sample displacement stage; 6. Diaphragm displacement stage; 7. Microscope objective; 8. Tube lens; 9. Area array camera; 10. PC computer; 11. Beam splitting prism; 12. Area array light source; 13. Test chart. Specific embodiments

[0023] The present invention will be further described in detail below with reference to the accompanying drawings.

[0024] In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0025] The present application discloses a multifunctional device capable of realizing the optical performance test of a superlens, including a first light source module 1, a diaphragm module, a moving component, a sample operation table, a microscopic optical path system, and a computer control and display system. The computer control and display system is the control center of the entire detection device, connected to the sample operation table and the microscopic optical path system, and is used to control the Z-axis movement of the sample operation table, the image analysis and processing of the microscopic optical path system, and the result display and output.

[0026] Refer to Figure 1 , the first light source module 1 is composed of a single-mode laser light source and an optical fiber collimator. The diaphragm module includes a fixed aperture diaphragm 2 and a sample aperture diaphragm 3. The sample aperture diaphragm 3 is three-dimensionally adjusted through the sample operation table, and the sample aperture diaphragm 3 can switch different apertures to adapt to lenses of different designs. The sample operation table includes an optical carrier table 4, a sample carrier table 5, and a diaphragm displacement stage 6. The optical carrier table 4 is used to place the sample, and the optical carrier table 4 is three-dimensionally adjusted along with the sample displacement stage 5. The sample displacement stage 5 controls the movement of the Z-axis through a motor. The diaphragm displacement stage 6 is used for the three-dimensional adjustment of the diaphragm module to make the diaphragm module coaxial with the sample. That is, the sample aperture diaphragm 3 is three-dimensionally adjusted through the diaphragm displacement stage 6.

[0027] The microscopic optical path system includes a microscopic objective lens 7, a tube lens 8, and a area array camera 9. The tube lens 8 and the microscopic objective lens 7 are detachably connected, and different models of microscopic objective lenses 7 are replaced according to the maximum image height of the product to be detected. One end of the tube lens 8 is connected to the microscopic objective lens 7, and the other end of the tube lens 8 is connected to the area array camera 9. The PC computer 10 obtains the sample surface and focal spot information in real time according to the defocus curve software and outputs the back focal data.

[0028] In some embodiments, it further includes an optical performance detection component. The optical performance detection component includes a power meter, and the power meter is located behind the optical carrier platform 4.

[0029] Continue to refer to Figure 1 , there are multiple sample placement slots on the optical carrier platform 4, and batch testing can be performed. Move the sample in the optical carrier platform 4 to the optical path center, place a power meter at the position of the sample behind it, record the current power P2, and record the power P1 after removing the sample. The transmittance P can be obtained according to the following formula:

[0030] P = P2 / P1 * 100% (1)

[0031] In addition, a beam splitting prism 11 is provided in this device, and the beam splitting prism 11 has different setting methods, which are specifically as follows.

[0032] As Figure 2 shown, adding a beam splitting prism 11 behind the aperture stop 2 can measure different samples simultaneously, improving the detection efficiency and the utilization rate of the light source. As Figure 3 shown, place the beam splitting prism 11 in front of the microscopic objective lens 7. The laser light source is split into two beams of light by the beam splitting prism 11 after passing through the meta-lens. One beam of light passes through the microscopic optical path system to complete the back focal test. The other beam of light is received by the power meter to test the transmittance, realizing the simultaneous test of the back focal and the transmittance, effectively shortening the measurement time.

[0033] In order to detect the MTF, field of view angle, and distortion, the first light source module 1 is replaced with a second light source module.

[0034] In some embodiments, the second light source module includes an area array light source 12 and a test chart 13. The test chart 13 includes a checkerboard test chart, a field of view angle test chart, and a distortion test chart. The checkerboard test chart is used to obtain the modulation transfer function value, and the field of view angle test chart is used to obtain the field of view angle and distortion value.

[0035] As Figure 4 shown, the area array light source 12 images and focuses the test chart 13 into the microscopic optical path system through the meta-lens. The test chart 13 includes a checkerboard test chart, a field of view angle test chart, and a distortion test chart. Switching different test charts can obtain the corresponding image information, and the modulation transfer function, field of view angle, and distortion are obtained after being processed and analyzed by the PC computer 10. The field of view angle and distortion can be obtained according to the following formula:

[0036] Field of View H = 2 * arctan(H / 2s) * 100% (2)

[0037] Field of View V = 2 * arctan(V / 2s) * 100% (3)

[0038] Field of View D = 2 * arctan(D / 2s) * 100% (4)

[0039] D TV = Δh / 2h * 100% (5)

[0040] Wherein, H is the object space width in the horizontal direction, V is the object space height in the vertical direction, D is the object space length in the diagonal direction, Δh is the difference between the actual object height and the theoretical object height, and h is the theoretical object height.

[0041] During the MTF measurement process, the microscopic optical path system images the checkerboard test card, captures the clear edges of the tilted checkerboard, then calculates the spatial frequency response (SFR) for its central field of view and edge field of view, differentiates the SFR curve to obtain the line spread function (LSF), and finally performs a Fourier transform (FFT) on it to obtain the MTF values at various frequencies.

[0042] After completing the MTF test, switch to the field of view test card, image the test card, read the field of view sizes in the horizontal, vertical, and diagonal directions from the image, and then calculate its field of view angle based on the distance from the test card to the metalens. After completing the above tests, switch to the distortion test card to perform the distortion test on the metalens.

[0043] In some embodiments, the area array light source 12 directly passes through the metalens and is focused into the microscopic optical path system, and the relative illuminance is obtained through processing and analysis by the PC computer 10.

[0044] As Figure 5 shown, place the beam splitting prism behind the tube lens 8. The imaging information focused by the metalens is divided into two parts, which are then received by area array cameras 9 of different wavelength bands at this time. Through processing by the PC computer 10, the imaging information at two wavelengths can be obtained, and parameters such as MTF at different wavelengths can be compared simultaneously.

[0045] In addition to measuring near-infrared metalenses, this detection device can also be used to detect the optical properties of mid-infrared and visible light metalenses, and only need to replace the first light source module 1, the second light source module, and the area array camera 9 with detectors and light sources corresponding to the working wavelength band of the metalens to be measured.

[0046] The above are only specific embodiments of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present disclosure can easily think of changes or substitutions, which should all be covered within the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.

Claims

1. A multifunctional device capable of realizing the optical performance test of a metalens, characterized in that: It includes a first light source module (1), a diaphragm module, a sample operation table, a microscopic optical path system, and a computer control and display system; The first light source module (1) is composed of a single-mode laser light source and an optical fiber collimator; The diaphragm module includes a fixed-aperture diaphragm (2) and a sample-aperture diaphragm (3). The sample-aperture diaphragm (3) is adjusted three-dimensionally through the sample operation table, and the sample-aperture diaphragm (3) can switch different apertures to adapt to lenses of different designs.

2. The multifunctional device according to claim 1, wherein: The sample operation table includes an optical carrier table (4) and a sample displacement table (5). The optical carrier table (4) is used to place the sample; the optical carrier table (4) is adjusted three-dimensionally along with the sample displacement table (5).

3. The multifunctional device according to claim 2, wherein: The sample operation table further includes a diaphragm displacement table (6), and the diaphragm displacement table (6) is used for three-dimensional adjustment of the diaphragm module to make the diaphragm module coaxial with the sample.

4. A multifunctional device according to claim 1, wherein: The microscopic optical path system includes a microscopic objective lens (7), a tube lens (8), and a area array camera (9). The tube lens (8) and the microscopic objective lens (7) are detachably connected; one end of the tube lens (8) is connected to the microscopic objective lens (7), and the other end of the tube lens (8) is connected to the area array camera (9).

5. A multifunctional device according to claim 1, characterized in that: It further includes an optical performance detection component. The optical performance detection component includes a power meter, and the power meter is arranged behind the optical carrier table (4).

6. The multifunctional device according to claim 1, characterized in that: The first light source module (1) is replaced by a second light source module, and the second light source module includes an area array light source (12) and a test chart (13).

7. A multifunctional device according to claim 1, wherein: A beam splitting prism (11) is arranged behind the fixed-aperture diaphragm (2).

8. A multifunctional device according to claim 4, characterized in that: A beam splitting prism (11) is arranged in front of the microscopic objective lens (7).

9. The multifunctional device according to claim 4, characterized in that: A beam splitting prism (11) is arranged behind the tube lens (8).

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