Optical film and method of manufacturing the same, backlight module, and display apparatus

Patent metadata

Field	Value
Publication number	US-2021003874-A1
Application number	US-202016917518-A
Country	US
Kind code	A1
Filing date	Jun 30, 2020
Priority date	Jul 4, 2019
Publication date	Jan 7, 2021
Grant date	—

Abstract

An optical film includes a light-transmissive substrate and a first annular lens group. The light-transmissive substrate has a first surface and a second surface opposite to each other. The first annular lens group is disposed on the second surface, and the first annular lens group is configured to allow light to pass through. The reflectivity of the first annular lens group decreases along a direction away from a central axis of the first annular lens group, and an extending direction of the central axis is the same as a thickness direction of the light-transmissive substrate.

First claim

What is claimed is:

1 . An optical film, comprising:
a light-transmissive substrate having a first surface and a second surface opposite to each other; and a first annular lens group disposed on the second surface, the first annular lens group being configured to allow light to pass through, wherein reflectivity of the first annular lens group decreases along a direction away from a central axis of the first annular lens group, and an extending direction of the central axis is the same as a thickness direction of the light-transmissive substrate.

2 . The optical film according to claim 1 , wherein the first annular lens group includes a plurality of first annular lenses, the plurality of first annular lenses are substantially concentric about the central axis and arranged radially adjacent to one another,
a distance between an inner surface of each first annular lens and the central axis in a radial direction of the first annular lens decreases along a direction that is parallel to the central axial and points toward the second surface; angles each between the second surface and a tangent plane of an inner surface of a corresponding first annular lens in the plurality of first annular lenses are acute angles and decrease in the direction away from the central axis.

3 . The optical film according to claim 2 , wherein the angles each between the second surface and the tangent plane of the inner surface of the corresponding first annular lens in the plurality of first annular lenses are different from each other, or
some of the angles each between the second surface and the tangent plane of the inner surface of the corresponding first annular lens in the plurality of first annular lenses are the same.

4 . The optical film according to claim 2 , wherein each of intersecting lines of the inner surface of the first annular lens and a plane passing through the central axis includes at least one of at least one straight line segment or at least one curved line segment;
the at least one straight line segment includes a straight line segment that is continuously inclined with respect to the second surface, or straight line segments that are connected in a stepped shape and intermittently inclined with respect to the second surface; and the at least one curved line segment includes a curved line segment that is continuously inclined with respect to the second surface or curved line segments that are connected in another stepped shape and intermittently inclined with respect to the second surface.

5 . The optical film according to claim 1 , wherein the first surface has a light coverage region and a non-light coverage region surrounding the light coverage region;
an orthographic projection of the first annular lens group on the first surface covers both the light coverage region and the non-light coverage region.

6 . The optical film according to claim 5 , further comprising a second annular lens group disposed on the first surface, wherein
the second annular lens group is located in the non-light coverage region and configured to reflect light, and the second annular lens group includes a plurality of second annular lenses arranged radially adjacent to one another.

7 . The optical film according to claim 6 , wherein refractive index of the first annular lens group is greater than refractive index of air; and/or,
refractive index of the second annular lens group is greater than the refractive index of air.

8 . The optical film according to claim 6 , wherein a distance between an outer surface of each second annular lens and its central axis in a radial direction of the second annular lens increases along the direction that is parallel to the central axis of the second annular lens and points toward the first surface.

9 . The optical film according to claim 8 , wherein angles each between the first surface and a tangent plane of an outer surface of a corresponding second annular lens in the plurality of second annular lenses are the same; or,
the angles between the first surface and the tangent plane of the outer surface of the corresponding second annular lens in the plurality of second annular lenses are different from each other.

10 . The optical film according to claim 8 , wherein each of intersecting lines of the outer surface of the second annular lens and a plane passing through the central axis of the second annular lens includes at least one of at least one straight line segment or at least one curved line segment;
the at least one straight line segment includes a straight line segment that is continuously inclined with respect to the first surface or straight line segments that are connected in a stepped shape and intermittently inclined with respect to the first surface; and the at least one curved line segment includes a curved line segment that is continuously inclined with respect to the first surface or curved line segments that are connected in another stepped shape and intermittently inclined with respect to the first surface.

11 . A backlight module, comprising:
the optical film according to claim 1 ; and a light-emitting device disposed at a side of the first surface of the light-transmissive substrate, wherein an orthographic projection of the light-emitting device on the first surface is within an orthographic projection of the first annular lens group on the first surface.

12 . The backlight module according to claim 11 , wherein the first surface has a light coverage region and a non-light coverage region surrounding the light coverage region; and the orthographic projection of the light-emitting device on the first surface is located in the light coverage region;
the orthographic projection of the first annular lens group on the first surface covers both the light coverage region and the non-light coverage region.

13 . The backlight module according to claim 11 , further comprising:
a reflective plate disposed at a side of the light-emitting device away from the first surface; and/or, a brightness enhancement film disposed at a side of the first annular lens group away from the light-transmissive substrate.

14 . The backlight module according to claim 11 , wherein the light-emitting device includes a mini light-emitting diode (Mini LED).

15 . A display apparatus, comprising:
a display panel; and the backlight module according to claim 11 , the backlight module being configured to provide backlight for the display panel.

16 . A method of manufacturing the optical film according to claim 1 , the method comprising:
forming the first annular lens group on the second surface of the light-transmissive substrate, wherein the reflectivity of the first annular lens group decreases along the direction away from the central axis, and the extending direction of the central axis is the same as the thickness direction of the light-transmissive substrate.

17 . The method according to claim 16 , wherein forming the first annular lens group on the second surface of the light-transmissive substrate includes:
forming the first annular lens group on the second surface through an etching process; or forming the first annular lens group on the second surface through an imprinting process.

18 . The method according to claim 17 , wherein forming the first annular lens group on the second surface through the imprinting process, includes:
forming a curable light-transmissive resin layer on the second surface; performing imprinting on the curable light-transmissive resin layer to form first annular

Assignees

• Beijing Boe Display Tech Co
• Boe Technology Group Co Ltd

Inventors

• Chen Ying
• Liu Shanshan
• Jia Lili
• Wang Bochang
• Li Donglei
• Liu Hui
• Yu Honghao

Classifications

• G02B19/0061

  the light source comprising a LED · CPC title

• G02B19/0028

  refractive and reflective surfaces, e.g. non-imaging catadioptric systems · CPC title

• G02B17/0868

  for light condensing, e.g. for use with a light emitter (details of lighting devices in general F21V) · CPC title

• G02B17/086

  wherein the system is made of a single block of optical material, e.g. solid catadioptric systems · CPC title

• G02F1/133607 Primary

  the light controlling member including light directing or refracting elements, e.g. prisms or lenses · CPC title