Light guide plate, display apparatus, and game machine

Patent metadata

Field	Value
Publication number	US-10802197-B2
Application number	US-201716340238-A
Country	US
Kind code	B2
Filing date	Sep 15, 2017
Priority date	Nov 18, 2016
Publication date	Oct 13, 2020
Grant date	Oct 13, 2020

Abstract

A light guide plate is transparent to visible light and is formed into a plate shape. The light guide plate includes a plurality of prisms 21 provided in a first region 22 on one surface 2b of the light guide plate, each of the plurality of prisms 21 including a reflection surface 21a that reflects the visible light, which is emitted from the light source 3 and enters the light guide plate 2 through an incoming surface 2a, toward the other surface 2c of the light guide plate 2. Then, for each of a plurality of first partial regions (22-1 to 22-n) in the first region 22, at least one of a direction of the reflection surface 21a of each prism 21 arranged in the first partial region and a ratio of a total of areas of the reflection surfaces 21a of each prism 21 to the first partial region is set according to an amount of light traveling from the first partial region toward a predetermined viewpoint such that brightness of the first region 22 changes spatially irregularly as seen from the predetermined viewpoint.

First claim

The invention claimed is:

1. A light guide plate that is transparent to visible light and is formed into a plate shape,
the light guide plate comprising:
an incoming surface opposed to a light source that emits the visible light; and
a plurality of prisms provided in a first region on one of surfaces of the light guide plate, each of the plurality of prisms including a reflection surface that reflects the visible light, which is emitted from the light source and enters the light guide plate through the incoming surface, toward the other surface of the light guide plate,
wherein an amount of light traveling from each of a plurality of first partial regions in the first region toward a predetermined viewpoint is randomly set such that brightness of the first region changes spatially irregularly as seen from the predetermined viewpoint, and
for each of a plurality of first partial regions in the first region, at least one of a direction of the reflection surface of each prism arranged in the first partial region and a ratio of a total of areas of the reflection surface to the first partial region is set according to an amount of light traveling from the first partial region toward the predetermined viewpoint.

2. The light guide plate according to claim 1 , wherein for each of the plurality of first partial regions, an angle along the one surface of the reflection surface with respect to a direction in which the reflection surface of each prism arranged in the first partial region and the light source directly face each other is set so as to become the direction according to the amount of light traveling from the first partial region toward the predetermined viewpoint.

3. The light guide plate according to claim 1 , wherein for each of the plurality of first partial regions, an inclination angle of the reflection surface of each prism arranged in the first partial region with respect to the one surface is set so as to become the direction according to the amount of light traveling from the first partial region toward the predetermined viewpoint.

4. The light guide plate according to claim 1 , wherein for each of the plurality of first partial regions, a number of prisms arranged in the first partial region is set to the ratio according to the amount of light traveling from the first partial region toward the predetermined viewpoint.

5. The light guide plate according to claim 1 , wherein for each of the plurality of first partial regions, a size of the reflection surface of each prism arranged in the first partial region is set to the ratio according to the amount of light traveling from the first partial region toward the predetermined viewpoint.

6. The light guide plate according to claim 1 , further comprising a plurality of prisms provided in a second region different from the first region on the one surface of the light guide plate, each of the plurality of prisms including a reflection surface that reflects the visible light, which is emitted from the light source and enters the light guide plate through the incoming surface, toward the other surface of the light guide plate,
wherein for each of a plurality of second partial regions in the second region, at least one of a direction of the reflection surface of each prism arranged in the second partial region and a ratio of a total of areas of the reflection surface to the second partial region is set according to the amount of light traveling from the second partial region toward the predetermined viewpoint such that brightness of the second region changes in a gradation manner along at least one of directions as seen from the predetermined viewpoint.

7. The light guide plate according to claim 6 , wherein for each of the plurality of first partial regions, the direction of the reflection surface of each prism arranged in the first partial region is set according to the amount of light traveling from the first partial region toward the predetermined viewpoint, and
for each of the plurality of second partial regions, the ratio of the second partial region is set according to the amount of light traveling from the second partial region toward the predetermined viewpoint.

8. A display apparatus comprising:
a light source configured to emit visible light;
a light guide plate that is transparent to the visible light and is formed into a plate shape; and
a controller configured to control turning on and off of the light source,
wherein the light guide plate includes:
an incoming surface opposed to the light source; and
a plurality of prisms provided in a first region on one of surfaces of the light guide plate, each of the plurality of prisms including a reflection surface that reflects the visible light, which is emitted from the light source and enters the light guide plate through the incoming surface, toward the other surface of the light guide plate,
an amount of light traveling from each of a plurality of first partial regions in the first region toward a predetermined viewpoint is randomly set such that brightness of the first region changes spatially irregularly as seen from the predetermined viewpoint, and
for each of a plurality of first partial regions in the first region, at least one of a direction of the reflection surface of each prism arranged in the first partial region and a ratio of a total of areas of the reflection surface to the first partial region is set according to an amount of light traveling from the first partial region toward the predetermined viewpoint.

9. The display apparatus according to claim 8 , wherein the light source includes a plurality of light emitting elements arrayed along a longitudinal direction of the incoming surface, and
the controller changes the light emitting element to be lit among the plurality of light emitting elements with lapse of time.

10. The display apparatus according to claim 9 , wherein for each of the plurality of first partial regions, an angle along the one surface of the reflection surface of each prism arranged in the first partial region with respect to a predetermined direction along the one surface is set so as to become the direction according to the amount of light traveling from the first partial region toward the predetermined viewpoint.

11. A game machine comprising:
a game machine body; and
a display apparatus provided on a surface of the game machine body on a side opposed to a player,
wherein the display apparatus includes:
a light source configured to emit visible light;
a light guide plate that is transparent to the visible light and is formed into a plate shape; and
a controller configured to control turning on and off of the light source,
the light guide plate includes:
an incoming surface opposed to the light source; and
a plurality of prisms provided in a first region on one of surfaces of the light guide plate, each of the plurality of prisms including a reflection surface that reflects the visible light, which is emitted from the light source and enters the light guide plate through the incoming surface, toward the other surface of the light guide plate,
an amount of light traveling from each of a plurality of first partial regions in the first region toward a predetermined viewpoint is randomly set such that brightness of the first region changes spatially irregularly as seen from the predetermined viewpoint, and
for each of a plurality of first partial regions in the first region, at least one of a direction of the reflection surface of each prism arranged in the first partial region and a ratio of a total of areas of the reflection surface to the first partial region is set according to an amount of light traveling from the first partial

Assignees

• Omron Tateisi Electronics Co

Inventors

• Takagi Yoshihiko

Classifications

• G02B6/0058 Primary

  varying in density, size, shape or depth along the light guide · CPC title

• A63F7/027

  electric · CPC title

• G09F13/20

  with luminescent surfaces or parts (luminescent compositions C09K11/00; light sources using luminescence F21K2/00) · CPC title

• G02B6/0061

  to provide homogeneous light output intensity · CPC title

• G02B6/0036 Primary

  2-D arrangement of prisms, protrusions, indentations or roughened surfaces · CPC title