阅读说明：本技术 一种超大视角汽车后视镜贴膜及扩大后视镜视角的方法 (Ultra-large visual angle automobile rearview mirror film and method for expanding visual angle of rearview mirror ) 是由 许峰 陈昱杰 郑鹏磊 申溯 于 2019-10-23 设计创作，主要内容包括：本发明涉及汽车零部件领域,针对现有技术中存在的后视镜视野不足问题,公开了一种超大视角汽车后视镜贴膜及扩大后视镜视角的方法,包括面A和面B,所述面A为平面,面B为菲涅尔反射面,即在薄膜上压印出菲涅尔面形,再镀上反射膜层；后视镜膜粘贴在单一曲率汽车后视镜上后,能够得到多曲率后视镜的大视场效果。本发明通过将菲涅尔面形用于反射,将其贴在已有的单一曲率汽车后视镜上,能够用低成本实现多曲率后视镜的效果,并且可以根据特殊需求对菲涅尔面形进行改变,相比于已有的扩大反射镜视野方法拥有价格低、适用范围广等优势。(The invention relates to the field of automobile parts, and discloses an automobile rearview mirror film with an ultra-large visual angle and a method for expanding the visual angle of a rearview mirror, aiming at the problem of insufficient visual field of the rearview mirror in the prior art, wherein the automobile rearview mirror film comprises a surface A and a surface B, the surface A is a plane, the surface B is a Fresnel reflection surface, namely, a Fresnel surface shape is impressed on a film, and then a reflection film layer is plated; after the rearview mirror film is pasted on the automobile rearview mirror with single curvature, the large view field effect of the rearview mirror with multiple curvatures can be obtained. According to the invention, the Fresnel surface is used for reflection and is attached to the existing single-curvature automobile rearview mirror, so that the effect of the multi-curvature rearview mirror can be realized at low cost, the Fresnel surface can be changed according to special requirements, and compared with the existing method for expanding the field of view of the reflecting mirror, the method has the advantages of low price, wide application range and the like.)

1. The automobile rearview mirror film with the ultra-large visual angle is characterized in that the film is made of transparent optical materials, the film comprises a surface A and a surface B, the surface A is a plane, the surface B is a Fresnel reflection surface, and at least one reflection film layer is plated on the outer surface of the Fresnel reflection surface; one side of the surface B is stuck with the automobile rearview mirror.

2. The super large visual angle automobile rearview mirror film as claimed in claim 1, wherein the stripe interval and depth on the fresnel reflection surface of said surface B determine the reflection visual angle.

3. The ultra-large viewing angle automobile rearview mirror film as claimed in claim 2, wherein the stripe interval and depth of the Fresnel reflection surface of the surface B are both less than 100 microns.

4. The extra-large visual angle automobile rearview mirror film as claimed in claim 1, wherein the equivalent reflection curvature R of light on said face B is in the range of 200mm-1800 mm.

5. The film of claim 1, wherein the plane B is a single center or a plurality of planes are arranged by taking the plane B as a center.

6. The automobile rearview mirror film with ultra-large visual angle of claim 1, wherein said automobile rearview mirror film is directly mounted on a single curvature reflector of an automobile, so that the original single curvature reflector can achieve the effect of a multi-curvature reflector.

7. An ultra-large visual angle automobile rearview mirror, characterized in that, it comprises the ultra-large visual angle automobile rearview mirror film of one of claims 1 to 6.

8. A method for widening the viewing angle of a rearview mirror, wherein the ultra-large viewing angle automobile rearview mirror film according to any one of claims 1 to 6 is attached to the surface of an automobile mirror.

Technical Field

The invention relates to the field of automobile parts, in particular to an automobile rearview mirror film with an ultra-large visual angle and a method for expanding the visual angle of a rearview mirror.

Background

Automobile rearview mirrors are located on the left side and the right side of an automobile, and automobile drivers are used for observing the conditions of the two sides and the rear of the automobile and are indispensable devices for ensuring driving safety. However, since a general automobile rearview mirror is a plane mirror or a spherical mirror, the defects of small visual field and blind area generally exist.

In order to eliminate the hidden trouble caused by insufficient view of the rearview mirror, automobile manufacturers have improved the structure of the rearview mirror, and for the reflector, the larger the curvature, the smaller the view field, so that the rearview mirror with multiple curvatures is applied. Multi-curvature mirrors that have appeared on the market are generally divided into double-curvature mirrors, for which three quarters close to the vehicle body are flat mirrors and the other quarter are small-curvature mirrors, and triple-curvature mirrors divide the reflecting surface into three parts, and the parts close to the vehicle body can also be seen by the driver when different curvatures are used. The multi-curvature rearview mirror has the advantages that the relation between the visual field of a driver and the scene distortion is balanced, but the sudden change of the curvature of the mirror surface splicing part can cause the deviation of the judgment of the driver on the distance, meanwhile, the multi-curvature rearview mirror is high in production cost, and a small number of middle and low-grade cars are used. The other solution is to stick a convex mirror with smaller curvature on the outer side of the single-curvature automobile rearview mirror to enlarge the visual field range of the driver, but the blind area is eliminated with lower cost, but the rear visual field picture is cracked, and the image of the small convex mirror is smaller, so that the attention of the driver is dispersed. More novel automobile rearview mirrors are proposed at the same time, for example, patent application No. CN201910243042.0 discloses that a combined lens rearview mirror with a mechanical structure is proposed, although a large field of view is obtained, the problem of edge image discontinuity caused by mirror surface splicing is generated, meanwhile, the use of the mechanical structure increases the manufacturing cost of the rearview mirror, and the whole rearview mirror structure needs to be replaced, so that the applicability of further popularization is poor.

Disclosure of Invention

Aiming at the problem of insufficient field of vision of the rearview mirror in the prior art, the invention provides the reflecting film directly used for the automobile rearview mirror.

In order to achieve the purpose, the technical scheme of the invention is as follows:

the film for the automobile rearview mirror with the ultra-large visual angle is made of a transparent optical material, and comprises a surface A and a surface B, wherein the surface A is a plane, the surface B is a Fresnel reflection surface, and at least one reflection film layer is plated on the outer surface of the Fresnel reflection surface; when the film is used, one side of the surface B is adhered to the automobile rearview mirror.

The working principle is as follows:

the Fresnel reflection surface has an equivalent curvature of R and the parallel light has a value of theta₁Incident on the surface A, the transparent optical material has a refractive index n₁The base angle of the sawtooth structure of the Fresnel reflection surface is theta₂The angle theta of the light reflected by the Fresnel reflecting surface₃＝arcsin(n₁sin(2θ₂+arcsin(sinθ₁/n₁) In which air has a refractive index of 1, when n is₁When the number of the refraction surfaces is not 1, namely when the transparent optical material is used as the protective surface, a refraction surface is also added, and because the surface shape of the Fresnel reflection surface can be equivalent to the collapse of the convex mirror, when the base angle of the sawtooth structure of the Fresnel reflection surface is increased along with the increase of the radius, theta is increased₃And the reflection angle is larger when the radius of the Fresnel surface shape is larger, and the reflection angle is not linear. Therefore, light rays are reflected by the inner surface of the Fresnel surface after penetrating through the plane A, the curvature radius of different view field angles of light emergent from the plane A is different, the Fresnel reflection film is pasted on the automobile rearview mirror with single curvature, the large view field effect of the automobile rearview mirror with multiple curvatures can be obtained, the Fresnel reflection surface coated with the reflection film is directly attached to the reflection surface of the original automobile rearview mirror to form a new reflection surface, and the single curvature reflection mirror can be directly changed into the multiple curvature reflection mirror under the condition that the structure of the original rearview mirror is not changed.

Preferably, the equivalent reflection curvature R of a ray on said face B ranges from 200mm to 1800 mm.

The film material is preferably transparent optical resin, and the material of the reflecting film is silver, chromium or the like.

Preferably, the fresnel reflection surface is designed to have two curvatures, and the equivalent curvatures of the inner circle and the outer circle are respectively 1800mm for R1 and 200mm for R2.

The light rays are refracted for the first time through the optical resin, then are reflected on the Fresnel reflection surface, and then the light rays are imaged after passing through the optical resin again. Compared with the Fresnel reflection surface type which is directly exposed in the air, the design can protect the Fresnel reflection surface type from the external influence. The reflecting field angle can be expanded without increasing the film thickness by replacing the traditional plane or large-curvature spherical reflecting surface with the Fresnel reflecting surface, the stripe interval and the depth on the Fresnel reflecting surface of the surface B determine the reflecting field angle, namely the field of view of the reflecting mirror after the reflecting film is attached is mainly related to the surface shape of the Fresnel surface, and the design of the Fresnel surface shape can be completed by LightTools software and the simulation of the reflecting field angle is carried out.

Preferably, the stripe interval and the depth of the Fresnel reflection surface of the surface B are both smaller than 100 micrometers and smaller than the limit which can be distinguished by naked eyes, the imaging quality is not influenced, the stripe interval of the Fresnel reflection surface shape is gradually increased from the center to the periphery, the reflection surface selects one part of an annular Fresnel surface shape, and the center of the Fresnel reflection surface coincides with the center of the reflector window.

Preferably, the surface B may be designed for a single fresnel reflection center or a plurality of fresnel reflection centers, and may be designed in an overall surface shape with different fresnel surface shapes according to different needs.

Preferably, the automobile rearview mirror film is directly installed on a single curvature reflector of an automobile, so that the original single curvature reflector realizes the effect of a multi-curvature reflector, the reflection curvature of the automobile rearview mirror film can be equivalent to the curvature of a spherical reflector, and the change of the film thickness caused by the change of the equivalent curvature can not be caused by the adoption of a Fresnel structure.

Based on the above scheme still provide an ultra large visual angle automobile rearview mirror, including above-mentioned ultra large visual angle automobile rearview mirror pad pasting.

Based on the scheme, the method for expanding the visual angle of the rearview mirror is also provided, and the automobile rearview mirror film with the ultra-large visual angle is attached to the surface of an automobile reflector. The attachment mode comprises double-sided adhesive tape, electrostatic adsorption, magnetic attraction and the like.

The reflector based on the ultra-large visual angle automobile rearview mirror film comprises a substrate and an ultra-large visual angle reflection film attached to the surface of the substrate.

The mode belt can directly change any plane into a reflecting surface with a large view field, and can be used for occasions needing large view field display, such as a large view field reflector, a road corner reflector and the like. The processing difficulty of the reflector is reduced, the substrate plane does not need to be coated, and the processing cost is greatly reduced.

Through the technical scheme, the automobile rearview mirror film with the ultra-large visual angle, provided by the invention, has the advantages that the Fresnel surface shape is used for reflection, the Fresnel surface shape is pasted on the existing automobile rearview mirror with the single curvature, the effect of the multi-curvature rearview mirror can be realized at low cost, the Fresnel surface shape can be changed according to special requirements, and the Fresnel surface shape is low in price and wide in application range compared with the existing method for expanding the visual field of the reflector.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below.

FIG. 1 is an axial structural view of a film for a rear view mirror of an automobile;

FIG. 2 is a radial cross-sectional view of an automotive rearview mirror film;

FIG. 3 is a schematic diagram of surface shape data of a Fresnel reflection surface;

FIG. 4 is a schematic diagram of a horizontal view comparison of a rearview mirror of an automobile;

FIG. 5 is a schematic view of a vertical field of view comparison of an automotive rearview mirror;

FIG. 6 is a schematic view of light reflected from the film of the rearview mirror;

FIG. 7 is a schematic axial view of a multi-center multi-curvature Fresnel reflection film;

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.