| 摘要 |
<P>PROBLEM TO BE SOLVED: To efficiently receive infrared signals regardless of a viewing distance. <P>SOLUTION: A light receiving part incorporated in a bridge part of shutter spectacles comprises an infrared sensor, a condenser lens, and an infrared filter. The infrared filter passes only an infrared component of incident lights. The condenser lens condenses transmission lights of the infrared filter. The condenser lens has a property such that a focal distance gets longer as a radial position gets larger. Even when an incident angle is large, a ratio of the incident lights which can be condensed on a light receiving face of the light receiving part is not drastically deteriorated. Even when the incident angle is large at a close viewing distance, light receiving efficiency at the light receiving part is good. <P>COPYRIGHT: (C)2012,JPO&INPIT |
