Patent ID: 8395578

Claim:
A backlight unit comprising: a light source including LEDs of three or more colors, the LEDs being assigned to a plurality of light-emitting regions; a chromaticity sensor for detecting a chromaticity of white light generated by the LEDs; a light-source driver section for driving the LEDs; and a backlight controller section for adjusting white light generated by the LEDs to have a predetermined chromaticity based on a detected chromaticity value by the chromaticity sensor; and a black signal supplier section for supplying a black inserting signal for causing an LCD panel to display black in a black signal period, the black inserting signal being sent to the backlight controller section; wherein the backlight controller section controls to drive the LEDs to emit lights sequentially in respective predetermined scanning light-emitting periods in a single frame and in respective additional light-emitting periods in the same frame responsive to write scanning of an image signal to the LCD panel, the additional light-emitting periods being outside a corresponding one of the scanning light-emitting periods; light emission of the LEDs in each of the additional light-emitting periods is performed in synchronization with supply of a black inserting signal from the black signal supplier section to the LCD panel; the additional light-emitting period is defined based on the black signal period, and the scanning light-emitting period is provided for scan type lighting; light emission of the LEDs in the respective additional light-emitting periods in the frame is performed in a time period from a time immediately after a turn on to a time the emitted white light is converged to the predetermined chromaticity; and the time period is shortened by the light emission of the LEDs in the respective additional light emitting periods.