| 摘要 |
A head unit of a photo detector for irradiating a target area with detection light having a pencil of rays substantially shaped like a belt in transverse section and receiving light reflected in the target area. The head unit includes a belt-like-light generation lens having different light gathering functions relative to two directions orthogonal to each other in the transverse section of the pencil of rays for generating detection light substantially shaped like a belt, a light emission section for emitting the detection light from a first interface of the belt-like-light generation lens through a second interface of the belt-like-light generation lens to the target area, and a light reception section for receiving reflected light incident on the light reception section through the first interface of the belt-like-light generation lens from the second interface. <IMAGE> |
