阅读说明：本技术 菲涅尔屏幕 (fresnel screen ) 是由 王霖 胡飞 于 2018-05-31 设计创作，主要内容包括：本发明的目的是提供一种菲涅尔屏幕,其包括：基底；微结构,其形成在所述基底的第一表面上；和反射层,其形成在所述微结构上,其中,所述反射层的反射率在10％～35％的范围内,优选为在20～25％的范围内。该菲涅尔屏幕能够提高良品率并降低成本,同时能够保证屏幕具有较佳的视觉效果。(it is an object of the present invention to provide a fresnel screen comprising: a substrate; a microstructure formed on a first surface of the substrate; and a reflective layer formed on the microstructure, wherein the reflective layer has a reflectance within a range of 10% to 35%, preferably within a range of 20 to 25%. This fei nieer screen can improve yields and reduce cost, can guarantee simultaneously that the screen has the visual effect of preferred.)

1. A fresnel screen, comprising:

A substrate;

A microstructure formed on a first surface of the substrate; and

A reflective layer formed on the microstructure,

Wherein the reflectivity of the reflecting layer is within the range of 10-35%, preferably within the range of 20-25%.

2. a fresnel screen according to claim 1, wherein the first surface is a viewer facing surface of the substrate.

3. A fresnel screen according to claim 1, wherein the first surface is a viewer-facing surface of the substrate, and the fresnel screen further comprises a surface diffusing structure formed on the viewer-facing surface of the substrate.

4. A fresnel screen according to claim 1, wherein the reflective layer is formed only in the regions of the microstructures that are illuminated by the projected light.

5. a Fresnel screen according to any one of claims 1 to 4, wherein the surface of the reflective layer has a roughness in the range 1 to 50 microns.

6. A Fresnel screen according to any one of claims 1 to 4, wherein the reflective layer has a thickness in the range 10 to 30 microns.

7. The Fresnel screen according to any one of claims 1 to 4, wherein the reflective layer comprises a reflective material which is a metallic reflective material such as aluminum flakes, aluminum powder, silver powder, or the like, a diffusing material which is an organic pigment or an inorganic pigment, and an absorbing material which is epoxy-based, acrylic-based, or silicone-based organic resin particles, or an inorganic scattering material.

8. A Fresnel screen according to any one of claims 1 to 4, wherein the scattering angle of the reflective layer is between 10 and 45 degrees.

9. A Fresnel screen according to claim 2 or 4, wherein said substrate is a black substrate, a grey substrate or a transparent substrate and said microstructures are black microstructures, grey microstructures or transparent microstructures, wherein the black substrate or grey substrate is formed by doping a black absorbing material in the material forming said substrate and the black microstructures or grey microstructures are formed by doping a black absorbing material in the material forming said microstructures.

10. a fresnel screen according to claim 3, wherein the substrate is a grey substrate or a transparent substrate and the microstructures are grey microstructures or transparent microstructures, wherein a grey substrate is formed by doping the material forming the substrate with a black absorbing material and wherein a grey microstructure is formed by doping the material forming the microstructures with a black absorbing material.

11. A Fresnel screen according to claim 2 or claim 4, wherein a layer of black absorbing material is adhered or sprayed to the surface of the substrate opposite to the surface on which the microstructures are formed.

12. A fresnel screen according to claim 3, wherein the roughness of the surface diffusing structure is in the range of 0.5-50 microns.

13. A Fresnel screen according to any one of claims 1 to 4 wherein the reflective layer is of uniform thickness and is 1/10 to 1/5 of the pitch of the microstructures.

Technical Field

The present invention relates to a fresnel screen.

Background

When ultra-short focus projection is used, a conventional white screen for performing ultra-short focus projection is easily interfered by ambient light. For example, in an environment where lights in a living room are bright, the contrast of a screen is low, and colors cannot be displayed well.

In order to improve the contrast of the screen, it is necessary to reduce the reflection of the screen to the ambient light and to maintain the optical gain of the screen as constant as possible. The wire grid screen in the prior art improves the contrast of a projection screen by forming a light absorbing layer on one side and a reflecting layer on the other side in a wire grid microstructure on the surface of the screen.

However, the wire grid screen with the wire grid microstructure cannot achieve good collimation characteristics of the light of the projector, and the white lambertian scattering coating applied on the surface of the screen reduces the gain of the screen, so that the effect of improving the contrast ratio is very limited.

Although the screen adopting the fresnel reflection structure also exists in the prior art, the structure is easy to generate a 'ghost' phenomenon caused by reflection on the ceiling, and the viewing experience of a user is influenced.

Disclosure of Invention

In order to solve the above problems, the present invention provides a fresnel light-resistant screen, which has a simple structure and a good light-resistant property to ambient light, is particularly suitable for the production and application of large-sized fresnel screens, can improve the yield and reduce the cost, and can ensure that the screen has a good visual effect.

In a first aspect the present invention provides a fresnel screen comprising: a substrate; a microstructure formed on a first surface of the substrate; and a reflective layer formed on the microstructure, wherein the reflective layer has a reflectance within a range of 10% to 35%, preferably within a range of 20 to 25%.

The Fresnel screen with the structure can avoid the ghost phenomenon generated in the prior art, and has the characteristics of high gain, high contrast and high uniformity.

Drawings

Fig. 1 is a front view of a fresnel reflection structure in the shape of a ring.

Fig. 2 is a schematic view illustrating the roughness of the surface of the reflective layer.

Fig. 3 is a sectional view of the configuration of the fresnel screen of embodiment 1 in the present invention.

fig. 4 illustrates the principle of the fresnel screen having the structure shown in fig. 3 for collimating projector light.

Fig. 5 illustrates the relationship between the radius of the microstructure in a fresnel screen and the angle of incidence α and the angle of emergent rays β.

Fig. 6 is a sectional view of the configuration of the fresnel screen of embodiment 2 in the present invention.

Fig. 7 illustrates a modified example structure of the fresnel screen shown in fig. 8.

Fig. 8 is a diagram illustrating the principle of the fresnel screen having the structure shown in fig. 6 for collimating projector light.

Fig. 9 is a sectional view of the configuration of the fresnel screen of embodiment 3 in the present invention.

Fig. 10a-d illustrate a process of forming a fresnel screen in example 3.

fig. 11a-e show how the microstructure is combined with the substrate.

Fig. 12a shows a structure in which a black absorbing material layer is pasted on the back surface of a substrate.

Fig. 12b shows a structure in which a black absorbing material layer is sprayed on the back of the substrate.

Detailed Description

Hereinafter, specific embodiments according to the present invention will be described in detail with reference to the accompanying drawings. It is emphasized that all dimensions in the figures are merely schematic and not necessarily to scale, thus not limiting. For example, it should be understood that the dimensions, ratios, etc. of the microstructure, reflective film, etc. components shown in the drawings are not shown to scale, but are merely for convenience of illustration and are not intended to limit the specific scope of the present invention.

Figure 1 shows a fresnel reflection structure in the form of a ring. In fig. 1, the horizontal direction is the left-right direction of the screen, and the vertical direction is the up-down direction of the screen. As shown in fig. 1, the microstructure is composed of a plurality of concentric rings.

In the Fresnel screen, a reflecting film is formed on the surface of the microstructure shown in figure 1, the reflecting film is formed by mixing reflecting materials, diffusion materials, absorption materials and auxiliary raw materials such as bonding glue, the reflectivity of the reflecting film is 10% -35%, the scattering angle is +/-10 degrees to +/-45 degrees, the thickness of the reflecting layer is 1/10-1/5 of the distance between the microstructures, and the reflecting layer is relatively uniformly attached to the surface of the microstructure. Wherein the microstructure pitch refers to the distance between adjacent geometric shapes repeatedly formed in the microstructure in a cross-sectional view. For example, taking fig. 3, which is a cross-sectional view illustrating embodiment 1 of the present invention, the distance d between the repeating portions in two adjacent geometries for forming microstructures in the figure is the microstructure pitch.

First, in the present invention, in order to improve the contrast of ambient light, the reflectance of the reflective film is set to be in the range of 10% to 35%, preferably in the range of 20% to 25%. However, reducing the reflectivity of the coating reduces both the reflection of projector light and ambient light, i.e., reduces the gain of diffuse reflection. Specifically, when the viewing angle of the diffuse reflection is ± 60 degrees, if the reflectance is 100%, the screen effect of a gain of 1.0 can be achieved, and when the reflectance of the screen is reduced to 25%, the gain of the diffuse reflection is up to 0.25. Therefore, in order to make the microstructure of the invention still generate about 1.0 gain, the reflecting layer of the invention can realize a scattering angle of +/-10 to +/-45 degrees, thereby improving the screen gain by compressing a visual angle. For a viewer watching television, the scattering angle of +/-20-30 degrees can meet the watching requirement of a common family. Therefore, the microstructure in the invention improves the gain of the reflecting layer with the reflectivity within the range of 10% -35% to the level larger than 1.0 by adding the diffusion material, on the other hand, most of the ambient light comes from the ceiling, but the scattering angle of the reflecting layer in the invention is smaller, and the large-angle ambient incident light can be reflected to the direction of the floor by the reflecting layer on the surface of the microstructure, and can not enter the visual field of audiences by diffuse reflection, so the invention can improve the contrast of the screen against the ambient light, and effectively reduces the reflection of the Fresnel screen to the ambient light while ensuring the light gain within the scattering angle range of the Fresnel screen.

In order to realize a reflective layer having the above-mentioned reflectance range of 10% to 35% and a scattering angle of ± 10 degrees to ± 45 degrees, the reflective layer includes a reflective material, an absorbing material, and a diffusing material as follows:

Reflective material: aluminum sheet, aluminum powder, silver powder and other metal reflective materials;

Black absorbing material: organic pigments (azo, etc.) and inorganic pigments (e.g., carbon black, graphite, metal oxide, etc.);

diffusion material: epoxy, acrylic, or silicone organic resin particles, or other inorganic scattering materials.

because the reflecting layer contains a mixture of aluminum sheets and aluminum powder in a certain proportion, a certain diffusion effect is formed on incident light. The reflecting layer makes the scattering angle of the incident light within the range of +/-10 to +/-45 degrees.

In addition, the reflecting layer may further include an auxiliary material and a solvent, the auxiliary material and the solvent including: the mixture of the leveling agent, the wetting agent, the defoaming agent and the like in a certain ratio is used for increasing the coating effect; the said product contains a mixture of anhydrous acetone, anhydrous xylene, anhydrous cyclohexanone, anhydrous butanone, ethyl acetate and anhydrous butyl acetate.

In addition, as shown in fig. 2, the surface of the reflective layer has rugged topography, that is, the surface of the reflective layer has a certain surface roughness, and further the surface roughness may be in the range of 1 to 50 micrometers. The surface can not generate dazzling light caused by mirror reflection of the Fresnel screen, and therefore the phenomenon of 'ghost' of the ceiling of the Fresnel screen is eliminated.

In the present invention, a rough surface can be obtained on the surface of the reflective layer by, for example:

Doping a certain proportion of large-size scattering particles or absorbing particles in a material for forming a reflecting layer, then spraying the material on the surface of the microstructure, and forming a rough surface after a solvent of the material is volatilized; or

Firstly, the material for forming the reflecting layer is sprayed on the microstructure, and then surface roughening treatment such as chemical corrosion, sand blasting and the like is carried out.

In order to maintain the alignment characteristics of the microstructure without changing the tilt angle of the microstructure, it is necessary that the reflective layer is uniformly coated in thickness on the surface of the microstructure. The thickness of the reflecting layer is within the range of 10-30 microns, and generally does not exceed 1/5 of the microstructure spacing. For example, the reflective layer can be coated on the surface of the microstructure by spraying, screen printing, etc., and the thickness of the reflective layer can be precisely controlled.

Hereinafter, a specific configuration of a fresnel screen having a reflection film formed on a surface of a fresnel reflection structure is explained by three specific embodiments. It will be understood by those skilled in the art, however, that this particular embodiment is merely illustrative of the principles of the fresnel screen of the present invention and is not intended to limit the invention.

in addition, the three embodiments described below can have the relevant features in the fresnel screen, for example, the reflectivity of the reflective film is 10% to 35%, and the scattering angle is ± 10 to 45 degrees, and thus, details are not repeated when the embodiments are specifically described below.