# US 7,609,336 B2 · Liquid crystal display device

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 7,609,336 B2
- Document ID: US7609336B2
- Status: Granted
- Kind: B2
- Application number: 11/934,960
- Filed: 2007-11-05
- Published: 2008-05-08
- Granted: 2009-10-27
- Earliest claimed: 2006-11-06
- Assignees: Sumitomo Chemical Company, Limited
- Inventors: Akiyoshi Kanemitsu; Motohiro Yamahara; Hiroyuki Kumasawa
- Web page: https://patentgrep.com/patent/US7609336B2

## CPC

- G02F 1/133606: {including a specially adapted diffusing, scattering or light controlling members}
- G02B 5/0242: {by means of dispersed particles}
- G02B 5/0278: {used in transmission}
- G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS

## Abstract

The present invention provides a liquid crystal display device capable of achieving natural and high-quality color display without reddish color shift, not only when viewed in the normal direction but also when viewed obliquely. A liquid crystal display device 1 of the present invention includes a light diffuser plate 3, a light source 2 disposed on the back side of the light diffuser plate 3, and a liquid crystal panel 30 disposed on the front side of the light diffuser plate 3, wherein the light diffuser plate 3 is constituted by dispersing light diffusing particles in a transparent material, and the absolute value of a difference Δn in the refractive index between the transparent material and the light diffusing particles and a 50% cumulative particle diameter D50 (μm) of the light diffusing particles satisfy a relation 0.01≦Δn×D50≦0.25 or 0.61≦Δn×D50≦0.75.

## Claims

### Claim 1

A liquid crystal display device comprising a light diffuser plate, a light source disposed on the back side of the light diffuser plate, and a liquid crystal panel disposed on the front side of the light diffuser plate, wherein
the liquid crystal panel has a liquid crystal cell constituted by interposing a liquid crystal between a pair of transparent electrodes that are disposed at a distance from each other, and the liquid crystal molecules are aligned in a direction substantially perpendicular to the transparent electrodes when no voltage is applied across the pair of transparent electrodes,
the light diffuser plate is constituted by dispersing light diffusing particles in a transparent material, and
an absolute value of a difference Δn in a refractive index between the transparent material and the light diffusing particles and a 50% cumulative particle diameter D50 (μm) of the light diffusing particles satisfy a relation 0.01≦Δn×D50≦0.25.

### Claim 2

A liquid crystal display device comprising a light diffuser plate, a light source disposed on the back side of the light diffuser plate, and a liquid crystal panel disposed on the front side of the light diffuser plate, wherein
the liquid crystal panel has a liquid crystal cell constituted by interposing a liquid crystal between a pair of transparent electrodes that are disposed at a distance from each other, and the liquid crystal molecules are aligned in a direction substantially perpendicular to the transparent electrodes when no voltage is applied across the pair of transparent electrodes,
the light diffuser plate is constituted by dispersing light diffusing particles in a transparent material, and
an absolute value of a difference Δn in a refractive index between the transparent material and the light diffusing particles and a 50% cumulative particle diameter D50 (μm) of the light diffusing particles satisfy a relation 0.61≦Δn×D50≦0.75.