Patent ID: 6912017

Claim:
A display device for displaying an image according to input image data that is digital data, said display device comprising: a light source for producing light; light-transmitting filters for separating the light from said light source into at least four kinds of light including white light, said light-transmitting filters including a white-transmitting filter for transmitting white light and non-white transmitting filters; a light valve for projecting each kind of light from said light-transmitting filters onto a screen; said white light-transmitting filter being used to display information corresponding to lower-order bits of said digital data; a signal converter portion to control said white light-transmitting filter using a control signal corresponding to said lower-order bits, said signal converter portion including input terminals for receiving non-white light signals and a brightness signal calculating unit for calculating the brightness of the non-white light signals; said non-white light-transmitting filters being used to display information corresponding to said higher-order bits of said digital data; a drive device directly coupled to said signal converter portion for creating control signals for controlling the light transmitting filters and light valve; and an integrated value of a transmissivity in a visible range of said white-transmitting filter is smaller than the combined integrated values of transmissivities in a visible range of said non-white transmitting filters; wherein brightness created by a first gray level represented via said white light-transmitting filter is ½ m (m is the number of lower-order bits) the brightness created by a first gray level represented via said non-white light-transmitting filters.