BACK-LIGHT UNIT HAVING A PLURALITY OF LUMINOUS ELEMENT AND CONTROL METHOD THEREOF

摘要

A backlight unit having a plurality of light emitting devices and a method for controlling the same are provided to improve a contrast ratio by adjusting the brightness of the backlight unit with use of an average brightness value of an image and a representative brightness value of each block. A light emitting device unit(110) includes a plurality of light emitting devices. A first calculating unit(120) calculates an average brightness value of an input image. A second calculating unit(130) divides the input image into a plurality of blocks and calculates a representative brightness value of each block. A brightness adjustment value calculating unit(140) determines a reference level value by using the average brightness value, determines a brightness adjustment factor of each block by using the representative brightness value of each block, and adds the reference level value to the brightness adjustment factor to calculate a brightness adjustment value of each block of the input image. A control unit(150) applies the brightness adjustment value of each block to control an output brightness of a light emitting device of the plurality of light emitting devices in a position corresponding to each block.