| 摘要 |
PROBLEM TO BE SOLVED: To realize miniaturization and lighting in weight and to maintain the dimensional accuracy of the fixed member of an optical part with respect to a picture projection device using a liquid crystal element. SOLUTION: A projection lens 34 is fixed on a reference surface provided with a positioning dowel 54 and a machine screw hole on the vertical surface side of an optical base 50, and an illumination system color separation unit, transmission type liquid crystal panels arranged in three directions and a cross dichroic prism are fixed on reference surfaces 57, 60 and 63 provided with positioning dowels 58, 61 and 64 and machine screw holes 59, 62 and 65 on the horizontal surface side of the optical base 50, respectively. The optical base 50 is constituted by inserting a metallic bottom board provided with a vertical surface part 51V and a horizontal surface part 51H in a molded resin part 52 so that a metal exposed part 68 is formed on one part of the optical base 50, whereby heat radiation is improved, the dimensional accuracy of the part is maintained and the miniaturization and the lighting in weight are realized.
|
