METHOD FOR MANUFACTURING CROSS DICHROIC PRISM

摘要

PROBLEM TO BE SOLVED: To prevent the light returning from the exit face side to a cross dichroic prism from exiting again from the exit face. SOLUTION: A first right angle face of a first right-angle prism is laminated with a first right-angle face having no dichroic film of a third right-angle prism to constitute a first right-angle prism pair in such a manner that the part of the first right-angle face where a first dichroic film is not formed of the first right-angle prism protrudes. Then a first right-angle face of a second right-angle prism is laminated with a first right-angle face having no dichroic film of a fourth right-angle prism to constitute a second right-angle prism pair in such a manner that the part of the first right-angle face where a first dichroic film is not formed of the second right-angle prism protrudes. The first right-angle prism pair is laminated with the second right-angle prism part by using the protruding part of the first right-angle face of the first right-angle prism and the protruding part of the first right-angle face of the second right-angle prism as the reference.