| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To prevent a lens barrel from deforming by temperature increase, in the vicinity of an image display element in a projection lens used for an image display with high luminance. <P>SOLUTION: A five-group lens barrel 35 is disposed on the image display element side which is closer than an aperture member. A light-shielding member 42 is provided with a reflecting region S, having reflectivity higher than those of the other portions on an outer surface, and is integrated with the five-group lens barrel 35. The reflecting region S is the outer circumference of an effective light flux diameter on the incident side of the five-group lens barrel 35, inclined with respect to a plane perpendicular to the optical axis, and is provided with an inclined surface that reflects incident light out of an effective light as an undesired light, in the outer circumferential direction deflected from the optical axis direction. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
