| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a reflective iris for adjusting the F-number of an elliptical lamp, and an optical device for effectively adjusting the F-number of an elliptical lamp. <P>SOLUTION: The reflective iris comprises a spherical convex mirror part and an optical opening passing through the spherical convex mirror part. In the reflective iris, the spherical convex mirror part performs retro-reflection at a part of a high light cone angle of a focused optical beam to return through an elliptical lamp, the part of the high light cone angle is emitted from the elliptical lamp with a lower light cone angle after retro-reflection, the part of the low light cone angle of the focused optical beam and the retro-reflected part of the high light cone angle are transmitted through the optical opening, so that an effective light cone angle of the elliptical lamp is made lower than the given light cone angle. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
