| 摘要 |
<P>PROBLEM TO BE SOLVED: To more surely prevent stray light from impinging on an image forming element. <P>SOLUTION: In a light tunnel 30, an incidence opening on which light impinges, an internal space in which the light impinging from the incidence opening travels while being repeatedly reflected, and an exit opening 11 from which the light traveling in the internal space is emitted are formed by a plurality of tabular members 12, and a thickness of the tabular members 12 at the exit opening 11 is smaller than that at the incidence opening. <P>COPYRIGHT: (C)2012,JPO&INPIT |
