Color synthesizing optical apparatus and projection type display apparatus

A projection type display apparatus comprising:

• a light source supplying light beams;
• a polarization separating/color separating optical system effecting polarization separation and color separation with respect to light beams emitted from said light source;
• a plurality of reflection type light valves modulating incident light beams based on image signals and letting the modulated light beams exit;
• a color synthesizing/analyzing optical system including polarization beam splitters corresponding to said plurality of reflection type light valves, and color-synthesizing and analyzing the light beams having exited said plurality of reflection type light valves;
• quarter wave plates disposed corresponding to said plurality of reflection type light valves in light paths extending from exit surfaces of said reflection type light valves to incident surfaces of said polarization beam splitters;
• and
• a projection optical system projecting images generated on said plurality of reflection type light valves;
• wherein a first light valve group is constructed of at least a first said reflection type light valve that lets a first light beam exit, which is not reflected or is reflected an even number of times in a light path until the first light beam exits said color synthesizing/analyzing optical system after having exited said first reflection type light valves;
• a second light valve group is constructed of at least a second said reflection type light valve that lets a second light beam exit, which is reflected an odd number of times in a light path until the second light beam exits said color synthesizing/analyzing optical system after having exited said second reflection type light valve;
• in a state where said first light valve group and said second light valve group are being energized to effect image-displaying, in one group of said first light valve group and said second light valve group, a phase advance axis of a corresponding quarter wave plate is disposed substantially in parallel to a predetermined axis within a surface of said reflection type light valve of said one group, which axis corresponds to a predetermined axis within the projection image field plane of that light valve;
• and
• in the other group of said first light valve group and said second light valve group in the same state, a phase advance axis of the corresponding quarter wave plate is disposed substantially perpendicularly to a predetermined axis within a surface of said reflection type light valve of said other group, which axis corresponds to a predetermined axis within the projection image field plane of that light valve.