in accordance with the preferred embodiment of invented projector 10 only optical combiner 44 is equipped with such an invented frame 78 it also is possible within the spirit and scope of the invention to mount optical splitter 42 in such an invented frame with the positional and orientational advantages attending thereto with first second third fourth and fifth frame members 80 82 84 86 88 fully assembled with the proper positioning and orientation determined at the time of assembly by conventional calibration methods a unitary optical combiner subassembly is produced that is readily mountable within projector 10 without any required repositioning or realignment or recalibration of the light valves relative to the prismatic cube such mounting may be made to frame 12 of projector 10 as by the use of a post or other suitable mounting means extending through structure 90 formed within first and second frame members 80 82 in the preferred embodiment of the invention structure 90 as may be seen best perhaps from fig7 includes four apertured tabs of which only three such tabs 92 94 96 are depicted located at corresponding corners thereof by any suitable mounting means not shown such as molded plastic posts that form a part of a molded outsert insert or clamshell assembly of the projector 39 s chassis also not shown in fig6 or 8 for the sake of clarity is means for controlling light valves 58.