A glass slit

Abstract

The utility model discloses a kind of glass slits, which are divided into light-transmitting area (2) and non-light-transmitting area (1). The width of the light-transmitting area (2) is 15 or 30, and the light-transmitting area (2) is coated with an anti-reflection film with a transmittance of more than 96%. The non-light-transmitting area (1) is coated with an absorbing film with an absorption rate of more than 96%. The preparation method of the glass slit involves substrate processing, gluing, film coating, and peeling, etc. The light-transmitting area (2) of the glass slit has a transmittance of more than 96%, ensuring the luminous flux of the optical system. The non-light-transmitting area (1) uses an absorbing film, avoiding stray light introduced by multiple reflections of traditional chrome plating on optical lenses. The preparation method avoids the large size error of traditional laser cutting and the burr phenomenon of the slit, improving the production qualification rate of the slit and reducing the cost.

Description

Technical Field

[0001] This utility model relates to the field of micro-nano optical design and manufacturing technology, and in particular to a glass slit. Background Technology

[0002] Hyperspectral imaging technology, as a key means of Earth remote sensing and target detection, can simultaneously acquire geometric, radiometric, and spectral information of targets. It plays an increasingly important role in fields such as ecological environment monitoring, natural resource surveys, disaster monitoring, agriculture, forestry, animal husbandry and fisheries, and urban planning.

[0003] An imaging spectrometer employing pushbroom remote sensing imaging consists of three parts: a front-mounted telescope objective, a spectral dispersive system, and a detector. The entrance slit of the imaging spectrometer connects the telescope and the spectrometer, and its main functions include: ① controlling the width of the incident beam; the entrance slit ensures that the radiation from the light source can be effectively focused onto monochromatic elements such as gratings by limiting the width of the incident beam; ② affecting spectral resolution and luminous flux; the geometric parameters of the entrance slit directly affect the spectral resolution and luminous flux of the spectrometer; ③ adapting the slit width to the spectral dispersive requirements of different wavelengths; a smaller slit width can improve spectral resolution but reduce luminous flux, while a larger slit width can improve luminous flux but reduce spectral resolution.

[0004] Chinese utility model patent CN201488810U discloses an optically transparent slit, comprising an optically transparent substrate, which includes a light-transmitting region (2) and an opaque region (1). One or both sides of the opaque region (1) are coated with a metal film. The width of the light-transmitting region (2) is no greater than 0.5 mm. The thickness of the metal film is 2–5 micrometers. The light-transmitting region (2) of this optically transparent slit is closed, without any slits, making maintenance more convenient, providing better sealing, expanding its application range, and extending its service life. The light-transmitting region (2) of this optically transparent slit has high edge quality, resulting in good imaging quality on the array detector and improving the image quality of the spectrometer. The light-transmitting area (2) of this application is only an optically transparent substrate, and the opaque area (1) is simply coated with a metal film on one or both sides. Although this application has the disadvantages of having a light-transmitting area, the transparent substrate has low reflection and transmittance, and the metal film area has reflection that introduces stray light. It cannot meet the requirements of a high signal-to-noise ratio and low stray optical system.

[0005] Chinese utility model patent CN209485535U discloses a slit element, including a light-transmitting substrate with a thin-film light-shielding layer on the substrate, and holes formed in the light-shielding layer. In this utility model, the substrate of the slit element does not require holes, which not only simplifies processing and reduces cost, but also prevents dust accumulation. The smooth substrate surface is also easy to clean, thus greatly improving the practicality and reliability of the slit element. However, this application uses a thin-film light-shielding layer on the light-transmitting substrate, which has the disadvantages of low reflectivity and low transmittance in the light-transmitting area, failing to meet the requirements of high signal-to-noise ratio optical systems.

[0006] Other conventional slit machining methods include wire cutting and laser cutting. The cutting speed directly affects the straightness of the vertical edge of the slit and defects around the slit. The connection between the starting and ending points of the cut requires post-cutting deburring and polishing, making it relatively inefficient, and wire cutting also produces some oil stains. Laser machining is more efficient than wire cutting, but because lasers cut materials at high temperatures, they tend to leave residue around the slit. This residue is black, difficult to clean, and often has a wavy texture. Laser machining can also alter the properties of materials due to the high temperature, which can affect some special materials. Summary of the Invention

[0007] In order to solve the above-mentioned problems in the existing technology, this utility model provides a glass slit that can effectively improve the large dimensional error and burr phenomenon of traditional laser cutting, improve the pass rate of slit production and reduce costs.

[0008] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0009] The purpose of this utility model is to provide a glass slit, including a light-transmitting area and an opaque area. The technical feature is that the light-transmitting area is coated with an anti-reflective film, which is composed of several layers of silica film with a thickness of 77nm~110nm and titanium dioxide film with a thickness of 10nm, stacked sequentially. The silica film is close to the substrate of the light-transmitting area. The opaque area is coated with an absorption film, which is composed of a 200nm thick silver film, several layers of silica film with a thickness of 91nm~115nm, and titanium dioxide film with a thickness of 5nm~22nm, stacked sequentially. The silver film is close to the substrate of the opaque area, and the silica film is close to the silver film.

[0010] Compared with the prior art, the present invention has the following technical effects:

[0011] This invention relates to a glass slit, comprising an antireflective coating layer consisting of several layers of silica film with a thickness of 77nm~110nm and titanium dioxide film with a thickness of 10nm, stacked sequentially, with the silica film layer close to the substrate of the light-transmitting area; and an absorption film consisting of a 200nm thick silver film layer and several layers of silica film with a thickness of 91nm~115nm and titanium dioxide film with a thickness of 5nm~22nm, stacked sequentially, with the silver film layer close to the substrate of the opaque area and the silica film layer close to the silver film layer. The antireflective coating of this application can increase the light flux of the system, and the absorption film of this application can absorb stray light.

[0012] The method for preparing a glass slit of this invention involves substrate processing, adhesive coating, film deposition, and peeling. This glass slit avoids the large dimensional errors and burr phenomenon of traditional laser cutting, thereby improving the slit production yield and reducing costs. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the glass slit structure in this embodiment;

[0014] Figure 2 This is the absorption rate curve of the opaque region of the glass slit in this embodiment;

[0015] Figure 3 This is the transmittance curve of the opaque area of ​​the glass slit in this embodiment;

[0016] Figure 4 This is the reflectance curve of the opaque area of ​​the glass slit in this embodiment;

[0017] Figure 5 This is the transmittance curve of the light-transmitting area of ​​the glass slit in this embodiment;

[0018] Figure 6 This is a flowchart of the glass slit fabrication process in this embodiment;

[0019] Figure 7 This refers to the size of the light-transmitting area of ​​the glass slit prepared by the method in this embodiment. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below in conjunction with specific embodiments and accompanying drawings. 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 scope of protection of this utility model.

[0021] like Figure 1The glass slit of this invention, as shown, includes a light-transmitting region 2 and an opaque region 1. The light-transmitting region 2 is coated with an anti-reflective film, which is composed of several layers of silica film with a thickness of 77nm~110nm and titanium dioxide film with a thickness of 10nm, stacked sequentially. The silica film is close to the substrate of the light-transmitting region. The opaque region 1 is coated with an absorption film, which is composed of a 200nm thick silver film, several layers of silica film with a thickness of 91nm~115nm, and titanium dioxide film with a thickness of 5nm~22nm, stacked sequentially. The total thickness of the absorption film is less than 1. The silver film is close to the substrate of the opaque region, and the silica film is close to the silver film. The anti-reflective film has an average transmittance of greater than 96% in the 400nm~2500nm wavelength range.

[0022] The width of the light-transmitting area can be set to 5μm~60μm, the transmittance is greater than 96%, and the average absorption rate is greater than 96% in the 400nm~2500nm wavelength range.

[0023] Furthermore, the substrate material for the glass slit can be quartz glass, which can be selected from, but is not limited to, JGS1, JGS2, JGS3, ULE, K9, etc.

[0024] Furthermore, the incident light working angle of the light-transmitting area 2 and the opaque area 1 of the glass slit is -28° to +28°.

[0025] No film peeling or damage was observed in the glass slit after a thermal vacuum test at -150℃ to 70℃.

[0026] like Figure 6 The method for preparing a glass slit includes the following steps: substrate processing, followed by sequential antireflection coating, resist coating, ultraviolet lithography, development, absorption coating, and stripping operations on the substrate, as detailed below:

[0027] The base processing flow consists of blank processing, rough grinding / fine grinding, polishing, and centering edge grinding.

[0028] The antireflection coating is deposited using magnetron sputtering at a temperature of approximately 70°C. The coating power ranges from 300W to 400W, and the coating gas is argon. The coating target material is the same as the film material.

[0029] The photoresist was applied by spraying, and the photoresist was a negative photoresist with a coating thickness greater than 3μm.

[0030] Ultraviolet lithography is performed using a mask contact lithography method, which lithographically prints the light-transmitting area. The lithography power is 15mW / cm²~20 mW / cm², and the lithography time is 5s~15s.

[0031] Ultraviolet lithography is performed using a mask contact lithography method. The photoresist is SU8 series. The light-transmitting area is lithographically lithographically lithographically 15mW / cm²~20 mW / cm², and the lithography time is 5s~15s.

[0032] Developing was performed using SU8 series developer for 20-40 seconds.

[0033] The absorption film is deposited using magnetron sputtering at a temperature of approximately 70°C. The deposition power ranges from 300W to 400W. Argon is used as the deposition gas, and the target material is the same as the film material.

[0034] Acetone and alcohol are used for peeling.

[0035] Table 1 shows the detailed coating data of titanium dioxide (TiO2) and silicon dioxide (SiO2) as film materials in this invention, and the preparation of the thin film in the light-transmitting region 2.

[0036] Table 1. Thin film data for light-transmitting zone 2

[0037] membrane Material Thickness (nm) 1 TiO2 10 2 SiO2 77 3 TiO2 10 4 SiO2 110 197

[0038] Table 2 shows the detailed coating data of silver (Ag), titanium (Ti) and silicon dioxide (SiO2) as film materials in this invention, and the preparation of thin films in the opaque region 1.

[0039] Table 2. Thin film data for opaque region 1

[0040] membrane Material Thickness (nm) 1 SiO2 99 2 Ti 5 3 SiO2 115 4 Ti 7 5 SiO2 115 6 Ti 11 7 SiO2 113 8 Ti 22 9 SiO2 91 10 Ag 200 778

[0041] like Figure 2 As shown, in this embodiment, the average absorption rate of the opaque region 1 of the glass slit is 98.1%; Figure 3 As shown, the transmittance of the opaque area 1 of this utility model is 0%; Figure 4 As shown, the average reflectance of the opaque area 1 of this utility model is 1.9%. Figure 5 The light-transmitting area 2 of this utility model has an average transmittance of 98.1%.

[0042] like Figure 7 As shown, the size of the light-transmitting region 2 of the glass slit prepared by the method of this embodiment is 14.51 μm.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate this utility model patent and are not intended to limit the technical solutions described in this utility model patent. Therefore, although this specification has described this utility model in detail with reference to the above embodiments, those skilled in the art should understand that modifications can still be made to this utility model; and all technical solutions and improvements that do not depart from the scope of this utility model should be covered within the scope of the claims of this utility model.

Claims

1. A glass slit, comprising a light-transmitting area (2) and an opaque area (1), characterized in that, The light-transmitting area (2) is coated with an anti-reflection film, which is composed of several layers of silicon dioxide film with a thickness of 77nm~110nm and titanium dioxide film with a thickness of 10nm stacked sequentially. The silicon dioxide film is close to the substrate of the light-transmitting area (2). The opaque area (1) is coated with an absorption film, which is composed of a 200nm thick silver film and several layers of silicon dioxide film with a thickness of 91nm~115nm and titanium dioxide film with a thickness of 5nm~22nm stacked sequentially. The silver film is close to the substrate of the opaque area (1), and the silicon dioxide film is close to the silver film.

2. The glass slit as described in claim 1, characterized in that: The width of the light-transmitting area (2) can be set to 5μm-60μm, with a transmittance greater than 96% and an absorption rate greater than 96%.

3. The glass slit as described in claim 1, characterized in that: The substrate material for the glass slit can be quartz glass.

4. The glass slit as described in claim 1, characterized in that: The total thickness of the absorption membrane is less than 1 μm.

5. The glass slit as described in claim 1, characterized in that, The antireflective membrane and the absorption membrane are suitable for the spectral range of 400nm to 2500nm.

6. The glass slit as described in claim 1, characterized in that, The incident light working angle of the glass slit is -28° to +28°.

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