Patent ID: 7566143

Claim:
A backlight apparatus for illuminating a color display panel from the back side, comprising: a light source section including a composite light source configured to mix light fluxes of different colors from a plurality of monochromatic light sources and irradiate the mixed light upon said color display panel and having a plurality of optical regions grouped for each arbitrary number of said monochromatic light sources; a light detecting light introducing plate in the form of an optically transparent elongated plate disposed so as to traverse the optical regions of said light source section and having at least one light pickup portion provided thereon corresponding to each of the optical regions; a plurality of light amount sensors for the individual colors provided at least on one of the opposite end faces of said light detecting light introducing plate in the longitudinal direction; and control means for successively detecting the light in the individual optical regions using said color light sensors for the individual colors and controlling the light amount balance of the light of the colors emitted from the monochromatic light sources grouped for the individual optical regions based on detection outputs of said light amount sensors for the colors.