A liquid crystal panel unit is attached to a light incident surface of a prism composite. The liquid crystal panel unit includes a panel frame plate holding a liquid crystal panel, and a fixation frame plate glued and fixed to the light incident surface. The panel frame plate is fastened to the fixation frame plate by screws through an intermediate frame plate. By using wedges, the position of the panel frame plate with respect to the light incident surface is adjusted. This allows the liquid crystal panel to be reliably positioned and fixed so that the deviation amount in pixel matching is minimized and the focus adjustment can be accomplished correctly.