| 摘要 |
<p>PURPOSE:To obtain highly accurate image quality by shortening a projecting distance. CONSTITUTION:The focal distance (f) of the whole lens group constituted of 1st-3rd lens groups 14, 15 and 16 is made shorter than a back focus (b.f.) formed between each image forming part 10, 11 or 12 and the 1st lens group, and an image formed by the each image forming part is read out by readout light, and then, made incident on a three-color synthesizing optical system 13 so as to be synthesized. And the optical image synthesized in such a way is image- formed by the 1st lens group, and the luminous flux emitted from the 1st lens group is made incident so that the luminous flux may be converged on the 3rd lens group by the 2nd lens group. Besides, the optical image formed by the 1st lens group is enlarged and projected on a screen 17 which is adjacently arranged by the 3rd lens group.</p> |
