Backlight device

• US 20040042234A1
• Filed: 08/28/2003
• Published: 03/04/2004
• Est. Priority Date: 08/30/2002
• Status: Abandoned Application

• Current Assignee: Toko KK
• Original Assignee: Toko KK
• Inventors: Otake, Tetsushi
• Application Number:
  US10/649,607
• Publication Number:
  US 20040042234A1
• Time in Patent Office: Days
• US Class Current: 362/561
• CPC Class Codes: G02B 6/005 provided by one optical element, or plurality thereof, placed on the light output side of the light guide
• CPC Class Codes: G02B 6/0068 Arrangements of plural sources, e.g. multi-colour light sources
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side
• CPC Class Codes: G02F 1/133622 Colour sequential illumination
• CPC Class Codes: G02F 2202/046 fluorescent
• CPC Class Codes: H05B 45/20 Controlling the colour of the light

Abstract

A backlight device obtains white light by mixing and synthesizing the three primary colors, the white light appearing as bright to the human eye as conventional white light; in addition, the backlight device is highly economical, in that it reduces power consumption by reducing the effective power input to the light-emitting diodes, and lengthens the lives of the light-emitting diodes.

In a backlight device comprising self-luminous-sources in the colors of red, green, and blue, the device mixing and synthesizing the three primary colors from the self-luminous sources into white light, in order to light a liquid crystal display device using a light-conducting plate and/or a light-scattering plate, the self-luminous-sources of the three primary colors are illuminated sequentially at different timings for each color, so that the light-generating timings partially overlap, achieving time-division light-emission.

Claims

1. A backlight device for lighting a liquid crystal display device, comprising:

self-luminous sources in primary colors of red, green, and blue, the three primary colors from the self-luminous sources being mixed and synthesized into white light; and

a light-conducting plate and/or a light-scattering plate;

the self-luminous sources of the three primary colors being illuminated sequentially at different timings for each color and so that the light-generating timings partially overlap, thereby achieving time-division light-emission.

2. The backlight device according to claim 1, wherein light-emitting diodes are used as the self-luminous sources of the three primary colors.

3. The backlight device according to claim 1, wherein a fluorescent body for generating light by light-absorption is provided to the light-conducting plate and/or the light-scattering plate.

4. The backlight device according to claim 3, wherein the phosphor comprises a light-accumulating fluorescent body or long-residual light phosphor.