| 摘要 |
A back light unit and an apparatus for driving the back light unit are provided to improve contrast by detecting the number of black data signals for one frame and controlling light transmissivity according to the detected number of black data signals. A back light unit includes a lamp assembly(32), a light guide plate(40), a reflector, at least one or more diffusers(42,48), at least one or more prism sheets(44,46), and a transmissivity control sheet(60). The lamp assembly generates light and irradiates the light to an LCD(Liquid Crystal Display) panel. The light guide plate guides the light emitted from the lamp assembly to the LCD panel. The reflector is located under the light guide plate and reflects light projected from the light guide plate. The diffuser diffuses light that passes through the light guide plate. The prism sheet transmits light that passes through the diffuser to the vertical direction of the LCD panel. The transmissivity control sheet is located between the diffuser and the LCD panel and controls light transmissivity in proportion to black data to be displayed on the LCD panel. |
