| 摘要 |
An oblique projection optical system enlarges an image formed on a display device surface, and obliquely projects the enlarged image on a screen surface. The oblique projection optical system has, in the order from a reduction side: a refraction optical portion having a positive optical power, a concave reflection surface having a positive optical power, and a convex reflection surface having a negative optical power. The refraction optical portion includes a rotationally symmetric coaxial refraction group. An intermediate image of the image formed on the display device surface is formed between the refraction optical portion and the concave reflection surface. An aperture stop image is formed between the concave reflection surface and the convex reflection surface. The concave reflection surface and the convex reflection surface fulfill prescribed conditional formulae.
|
