To provide a technique for obtaining a desired brightness profile and better color uniformity extending over a light-emitting area of an illumination device using a multi-color light-emitting diode (LED), especially, an illumination device such as a backlight for an LCD.
A backlight uses an array of red, green, and blue LEDs in a mixing chamber. The mixing chamber has reflecting surfaces and a top opening for illuminating LCD layers. The desired brightness profile and better color uniformity are obtained by using techniques including steps of: arranging the LEDs in certain sequences and patterns; providing a specular ring at the base of each LED; attenuating the brightness of the LEDs at the edges; and using widely separated diffusers in the mixing chamber. The arrangement, selection, and control of the multicolored LEDs may be adjusted to achieve any desired white point specified by the display manufacturer.
KUPPENS SIMON
SCHRAMA CHARLES
MARTYNOV YOURII
PFEFFER NICOLA
KONIJN HUUB
| JP2004342587A | 2004-12-02 | |||
| JP2003330424A | 2003-11-19 | |||
| JP2000133006A | 2000-05-12 | |||
| JPS56123572A | 1981-09-28 | |||
| JP2002231037A | 2002-08-16 | |||
| JP2003178615A | 2003-06-27 |
Fumiaki Otsuka
Toshio Imajo
Takaki Nishijima