A reflective film with a high range of high incidence angles and reflectivity

Abstract

The utility model relates to a kind of reflective film of high incidence angle range and reflectivity, including substrate, the reflective surface of the substrate is sequentially provided with aluminium oxide film layer, pure aluminium film layer, silicon dioxide film layer, trititanium pentoxide film layer, silicon dioxide film layer, trititanium pentoxide film layer and silicon dioxide film layer along its direction of departure sequence.The utility model can expand design incidence angle range, also can improve the reflectivity of light in the incidence angle range.

Description

Technical Field

[0001] This invention belongs to the field of reflective medium technology, and specifically relates to a reflective film with a high incident angle range and high reflectivity. Background Technology

[0002] A reflective coating is a functional thin film that enhances surface reflectivity through optical design. It utilizes the principle of multi-beam interference or the high extinction coefficient of metallic materials to reflect light energy. The coating materials typically include metals such as aluminum, silver, gold, and copper, as well as alternating structures of high and low refractive index media. Reflective coatings are widely used in systems such as optical mirrors, lasers, and space telescopes to reduce light loss and improve equipment performance.

[0003] Currently, existing reflective films are designed with a relatively small incident angle range, typically ±15°. If the incident light exceeds this range, the reflectivity will decrease drastically. Furthermore, if the reflective film is highly reflective at small angles, its reflectivity will decrease at larger angles; conversely, if it is highly reflective at large angles, its reflectivity will decrease at small angles. Conventional reflective films have a narrow high-reflectivity bandwidth; therefore, when the incident angle changes, the reflectivity curve shifts relative to the angle, resulting in a decrease in reflectivity.

[0004] Therefore, a reflective film with a high incident angle range and reflectivity is provided, which can improve the incident angle range and also improve the reflectivity of light within the incident angle range. Utility Model Content

[0005] This invention provides a reflective film with a high incident angle range and high reflectivity, which can solve the above problems.

[0006] The technical solution adopted in this utility model is as follows:

[0007] A reflective film with a high incident angle range and reflectivity includes a substrate, wherein an aluminum oxide film layer, a pure aluminum film layer, a silicon dioxide film layer, a titanium pentoxide film layer, a silicon dioxide film layer, a titanium pentoxide film layer, and a silicon dioxide film layer are sequentially disposed on the reflective surface of the substrate along the direction of distance away.

[0008] Furthermore, from the direction away from the substrate, the thickness of the aluminum oxide film is 50±2nm, the thickness of the pure aluminum film is 100±2nm, the thickness of the silicon dioxide film is 83±2nm, the thickness of the titanium pentoxide film is 54±2nm, the thickness of the silicon dioxide film is 178±2nm, the thickness of the titanium pentoxide film is 100±2nm, and the thickness of the silicon dioxide film is 105±2nm.

[0009] Furthermore, from the direction away from the substrate, the thickness of the aluminum oxide film is 50 nm, the thickness of the pure aluminum film is 100 nm, the thickness of the silicon dioxide film is 83 nm, the thickness of the titanium pentoxide film is 54 nm, the thickness of the silicon dioxide film is 178 nm, the thickness of the titanium pentoxide film is 100 nm, and the thickness of the silicon dioxide film is 105 nm.

[0010] Furthermore, the substrate is a PC substrate.

[0011] Compared with the prior art, the beneficial effects of this utility model are:

[0012] 1. By reasonably setting different coating media on the substrate, the design incident angle can be increased to 0°~70°. Within this design incident angle range, the average reflectivity of most visible light (working wavelength 400nm~700nm) can be maintained at greater than 92%, which greatly improves the design incident angle and reflectivity.

[0013] 2. The reflective film provided by this utility model has a simple structure, requires fewer processing equipment, is easy to process and produce, helps to reduce production costs, and is suitable for mass production. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0015] Figures 2 to 7 The reflectivity test results are shown in the figure, which are obtained when visible light with wavelengths of 400nm to 700nm is irradiated onto the reflective film of this utility model at incident angles of 6°, 15°, 30°, 45°, 60° and 70°.

[0016] Figure 8 The experimental results for each film layer and its corresponding sensitivity coefficient value are shown in the figure (the larger the film layer number, the farther away it is from the substrate);

[0017] In the figure: 1. Substrate; 2. Aluminum oxide film; 3. Pure aluminum film; 4. Silica film; 5. Titanium pentoxide film. Detailed Implementation

[0018] To better understand the technical content of this utility model, specific embodiments are provided below, and the utility model will be further described in conjunction with the accompanying drawings.

[0019] See Figure 1 This utility model provides a reflective film with a high incident angle range and reflectivity, including a substrate 1. On the reflective surface of the substrate 1, an aluminum oxide film layer 2, a pure aluminum film layer 3, a silicon dioxide film layer 4, a titanium pentoxide film layer 5, a silicon dioxide film layer 4, and a titanium pentoxide film layer 5 are sequentially arranged along the direction away from the substrate.

[0020] Preferably, along the direction away from the substrate 1, the thickness of the aluminum oxide film 2 is 50±2nm, the thickness of the pure aluminum film 3 is 100±2nm, the thickness of the silicon dioxide film 4 is 83±2nm, the thickness of the titanium pentoxide film 5 is 54±2nm, the thickness of the silicon dioxide film 4 is 178±2nm, the thickness of the titanium pentoxide film 5 is 100±2nm, and the thickness of the silicon dioxide film 4 is 105±2nm.

[0021] Preferably, along the direction away from the substrate 1, the thickness of the aluminum oxide film 2 is 50 nm, the thickness of the pure aluminum film 3 is 100 nm, the thickness of the silicon dioxide film 4 is 83 nm, the thickness of the titanium pentoxide film 5 is 54 nm, the thickness of the silicon dioxide film 4 is 178 nm, the thickness of the titanium pentoxide film 5 is 100 nm, and the thickness of the silicon dioxide film 4 is 105 nm.

[0022] Preferably, substrate 1 is a PC substrate.

[0023] The basic principle of this utility model:

[0024] To ensure the reflective film provides high reflectivity for common visible light in the 400nm–700nm range at ultra-wide incident angles (0°–70°), this design first deposits aluminum oxide and pure aluminum as a base layer on substrate 1, followed by alternating layers of titanium pentoxide and silicon dioxide. The reflectivity at different incident angles is improved by controlling the thickness of different layers, thus maintaining high reflectivity across an ultra-wide incident angle range. The ultra-wide incident angle reflective film uses a PC substrate. The film material is evaporated and deposited onto the PC substrate surface using PVD deposition. Seven layers are sequentially deposited onto the surface of PC substrate 1, from closest to furthest from the PC substrate 1: aluminum oxide, pure aluminum film, silicon dioxide, titanium pentoxide, silicon dioxide, titanium pentoxide, and silicon dioxide.

[0025] Membrane structure and thickness design specifications:

[0026] 1) The first layer, the undercoat, is made of aluminum oxide (ANO). ANO has excellent bonding properties with PC material. The main reflective film layer is an aluminum layer, and the reflective enhancement layer is an alternating layer of titanium pentoxide (high refractive index) and silicon dioxide (low refractive index). The selected materials have a refractive index of 2.41-2.45 for titanium pentoxide, 1.43-1.47 for silicon dioxide, and 1.65-1.69 for aluminum oxide.

[0027] 2) PC substrate processing:

[0028] Before plating, the PC substrate is cleaned using an ultrasonic cleaner, and then baked at 100±5℃ for 5 hours. Ultrasonic cleaning removes dirt and foreign matter from the substrate surface, while baking removes residual moisture and gas (residual moisture and gas can cause aluminum oxidation and reduce reflectivity).

[0029] 3) Selection of coating equipment and setting of relevant parameters:

[0030] Coating equipment: Electron beam evaporation equipment;

[0031] Vacuum degree confirmation: Before the film material evaporates, the equipment cavity is evacuated until the vacuum degree is 7×10. -4 Pa, a high vacuum environment can produce thin films with good density, high purity and uniform coating;

[0032] Confirmation of cavity environment temperature: The vacuum chamber environment temperature is 90℃. The high temperature of 90℃ will not affect the deformation of PC substrate 1, and at the same time can improve the adhesion between substrate 1 and film layer.

[0033] Evaporation rate parameters:

[0034] The first layer is an aluminum oxide film, with a deposition rate of 0.5 nm / s.

[0035] The second pure aluminum film layer 3 has a deposition rate of 3.6 nm / s.

[0036] The third silicon dioxide film layer 4 has a deposition rate of 0.8 nm / s.

[0037] The fourth titanium pentoxide film layer 5 has a deposition rate of 0.5 nm / s.

[0038] The fifth silicon dioxide film layer 4 has a deposition rate of 0.8 nm / s.

[0039] The sixth titanium pentoxide film layer 5 has a deposition rate of 0.5 nm / s.

[0040] The 7th silicon dioxide film layer 4 has a deposition rate of 0.8 nm / s.

[0041] See Figures 2 to 7 ,

[0042] The average reflectivity remains high, greater than 92%, within the operating wavelength range of 400nm to 700nm; specifically:

[0043] The average reflectance is 92.32% at 6°; 92.22% at 15°; 92.12% at 30°; 92.08% at 45°; 92.01% at 60°; and 92.50% at 70°.

[0044] See Figure 8 ,

[0045] This diagram illustrates the film layer sensitivity of the high-reflectivity optical film of this invention. The horizontal axis represents different film layers, and the vertical axis represents the sensitivity coefficient of that film layer. A higher sensitivity coefficient indicates greater sensitivity to thickness errors. The diagram shows that the sensitivity coefficients of the seven film layers are all below 10⁻⁶, indicating extremely low sensitivity. This demonstrates good tolerance for thickness errors that may occur during production, thus contributing to production stability.

[0046] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A reflective film with a high incident angle range and high reflectivity, characterized in that: The substrate includes a substrate on which an aluminum oxide film, a pure aluminum film, a silicon dioxide film, a titanium pentoxide film, a silicon dioxide film, a titanium pentoxide film, and a silicon dioxide film are sequentially disposed on the reflective surface of the substrate in the direction of distance away from it. Along the direction away from the substrate, the thickness of the aluminum oxide film is 50±2nm, the thickness of the pure aluminum film is 100±2nm, the thickness of the silicon dioxide film is 83±2nm, the thickness of the titanium pentoxide film is 54±2nm, the thickness of the silicon dioxide film is 178±2nm, the thickness of the titanium pentoxide film is 100±2nm, and the thickness of the silicon dioxide film is 105±2nm.

2. The reflective film with high incident angle range and reflectivity according to claim 1, characterized in that: From the direction away from the substrate, the thickness of the aluminum oxide film is 50 nm, the thickness of the pure aluminum film is 100 nm, the thickness of the silicon dioxide film is 83 nm, the thickness of the titanium pentoxide film is 54 nm, the thickness of the silicon dioxide film is 178 nm, the thickness of the titanium pentoxide film is 100 nm, and the thickness of the silicon dioxide film is 105 nm.

3. The reflective film with high incident angle range and reflectivity according to claim 1, characterized in that: The substrate is a PC substrate.

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