Patent ID: 9148615
Filing Date: 2015-09-29
Classification: G03B,H04N

Abstract:
1. A video display device that modulates, based on video signals, the intensity of the light emitted from LED light sources of predetermined colors and projects the light onto a screen, the video display device comprising: a light source driving section that drives said LED light sources to emit light; a detection section that detects maximum signal levels for the respective colors from said video signals for an amount of n screens (n is an integer equal to or larger than one); a calculation section that calculates amplification factors for the respective colors based on said maximum signal levels detected by said detection section; an amplification section that amplifies signal levels of said video signals based on the amplification factors for the respective colors calculated by said calculation section in a power saving mode for reducing power consumption; and a control section that controls drive current values of said LED light sources supplied to said light source driving section so as to cancel amplification amounts of the brightnesses of said respective LED light sources, the amplification amounts corresponding to amplification amounts of the signal levels of said video signals amplified by said amplification section, wherein said plurality of video display devices include one master device and slave devices, and in said power saving mode, said slave devices transmit the amplification factors for the respective colors to said master device, and said master device extracts the smallest amplification factors for the respective colors from the amplification factors of all the video display devices constituting said multi-screen display device and transmits the smallest amplification factors to said slave devices.