To decrease the number of components of an optical prism unit and to improve the heat radiation of an optical prism unit.

A liquid crystal projector is equipped with a U-shaped panel fixation member 27 having panel fixation frame parts 27a for fixing liquid crystal panels 22, 23, and 24 opposite to three surfaces of light incidence of a dichroic prism 21 where a phase difference plate 30 and a polarizing plate 29 are stuck; and the liquid crystal panels 22, 23, and 24 on which transparent glass substrates 28 having high heat conductivity are stuck are fixed to the respective panel fixation frame parts 27a with adhesives with high heat conductivity while registration adjustments are made.