| 摘要 |
A distance measuring apparatus for measuring a distance to a target by measuring a period of time in which a light beam goes to the target and returns, said distance measuring apparatus comprising: a light source (130,502) for emitting a light beam; a light transmitting lens (101) for transmitting the light beam emitted from the light source (130,502); and a light receiving element (314,509) for receiving the light beam reflected by the target, the light transmitting lens (101) includes in a portion thereof a diffusion element (110) for deflecting the light beam (110), and the diffusion element includes a number of small prisms (102) provided in a portion of the light transmitting lens (101), said number of small prisms (102) having different apical angles ( delta ) in accordance with distances from the optical axis (100), and further has a shape in which an intensity of the light beam received by the light receiving element (314,509) is constant in a region having a constant width (2a) and extending in parallel with the optical axis (303) forward from the distance measuring apparatus (310). <IMAGE> |
