A light emitting device provided with a plurality of types of light sources having different light emitting colors and with a light emission control means for allowing light to emit, during a specified period of monitoring a light emitting intensity, from at least one light source out of the plurality...http://www.google.com.au/patents/US7510300?utm_source=gb-gplus-sharePatent US7510300 - Light emitting device and display apparatus and read apparatus using the light emitting device
