BACKLIGHT DEVICE FOR LCD DISPLAYS

摘要

A backlight unit of an LCD is provided to spread infrared energy over a wide band, thereby performing a stable operation without affecting the infrared remote control when illuminating the LCD. A backlight unit(1) of an LCD comprises a light emitting source including a cold cathode fluorescent tube or a hot cathode fluorescent tube, which is lighted by a high-frequency power source. Brightness of the light emitting sources is adjusted by PWM(Pulse Width Modulation)-controlling the high-frequency power source. High-frequency energy from the high-frequency power source is spread over a wide band along a frequency axis so that PWM-modulated infrared energy generated from the backlight unit is not concentrated at a specific frequency but is spread over the wide band.