| 摘要 |
<p>PURPOSE:To attain miniaturization, high luminance and high contrast by being composed of a single light source, two dichroic mirrors, projecting system composed of three reflection type liquid crystal elements and projecting lens, and a writing system having a semiconductor laser as a main part. CONSTITUTION:White projected light irradiated from a xenon arc lamp is narrowed down by a lens system 13 and reflected to a dichroic mirror 121 side by a mirror 141 provided on a central part in a projecting lens 16 by an off-axis optical system. Out of the reflected white light, only a blue light component is reflected by the dichroic mirror 121, reflected by a mirror 142 and made incident on a liquid crystal element 151. Out of red and green light components to permeate through the dichroic mirror 121, only the green light component is reflected by a dichroic mirror 122, reflected by a mirror 143 and made incident on a liquid crystal element 152. The red one permeates through the dichroic mirrors 121 and 122 and is made incident on a liquid element 153. Thus, the miniaturization, the high luminance and the high contrast can be attained.</p> |
