Patent ID: 7789527
Filing Date: 2010-09-07
Classification: G02F,G09G

Abstract:
1. A backlight device for illuminating with a white light, the backlight device comprising: a transmissive color liquid crystal display panel from a back side of the backlight device, the transmissive color liquid crystal display panel including a color filter employing a red light color filter, a green light color filter, and a blue light color filter; a light source including a plurality of red light emitting diodes for radiating red light, each red light emitting diode having a peak wavelength λpr such that 625 nm ≦λpr ≦685 nm, a plurality of green light emitting diodes for radiating green light, each green light emitting diode having a peak wavelength λpg such that 505 nm≦λpg≦540 nm, and a plurality of blue light emitting diodes for radiating blue light, each blue light emitting diode having a peak wavelength λpb such that 420 nm≦λpb≦465 nm; a mixing means for color mixing the red light, the green light and the blue light, radiated from the light source, to generate white light; wherein a light emission intensity of the red light, the green light and the blue light, radiated from the red light emitting diode, the green light emitting diode and the blue light emitting diode, respectively, is adjusted so that a half value width hwr of a spectrum of the red light, a half value width hwg of a spectrum of the green light and a half value width hwb of a spectrum of the blue light are such that 20 nm ≦hwr≦25 nm, 30 nm≦hwg≦40 nm and 25 nm ≦hwb ≦30 nm, respectively, wherein the half value width hwb of the spectrum of the blue light is, on average, about 5 nm wider than the half value width hwr of the spectrum of the red light, and wherein a ratio of peak intensity of the red light, the green light, and the blue light is about 0.9:0.6:1.