Patent attributes
Aspects of the invention provide a projector capable of comparatively easily achieving a contrast ratio higher than the original contrast ratio of the liquid-crystal light valve by a simple mechanism. The illumination light modulated by liquid-crystal light valves, i.e., image light, can be combined together in a cross dichroic prism, and then light intensity of suitable pixels is reduced by a proper amount by a liquid-crystal light valve, and then sent to a projection lens. The image light entering the projection lens can be projected to a projection surface. Because the light intensity of the image light formed by the liquid-crystal light valves is appropriately attenuated at suitable pixel areas by the liquid-crystal light valve, image light projection with a contrast ratio exceeding by far the contrast ratio achievable by the liquid-crystal light valves alone is possible due to cumulative light-intensity adjustment.