ILLUMINATION DEVICE AND PROJECTION TYPE DISPLAY DEVICE USING THIS ILLUMINATION DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an illumination device for a projection type display device which does not have a significant effect on the uniformity of illumination even if the luminous flux for illumination to a light valve is partially shut off. SOLUTION: This device has beam-condensing means (1 and 2) which condense the light beams from a luminous body and forms a beam-condensing image, a light mixing element 3 which has an incident end face 31 near the position of the formed beam-condensing image, decreases the unevenness of the brightness of the beam- condensing image of the luminous body and forms an even surface of the light source on the exit end face 32 and a transmission optical system which is arranged with first and second lens groups (45 and 46) successively from the light mixing element 3 to the surface 5 to be illuminated of the light valve, puts the incident end face 31 of the light mixing element and a virtual face of a position where a diaphragm 6 near the final face of the lens means nearest the surface to be illuminated constituting the second lens group into a first optical conjugate relation and the exit end face of the light mixing element 3 and the surface 5 to be illuminated into a second conjugate relation by the first and second lens groups and emits the luminous flux for illumination in a non-telecentric state from the exit end face of the light to the side of the surface 5 to be illuminated.