| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a light projection device able to couple light from a light source to an optical fiber at high coupling efficiency, and to provide a sensor having the same. <P>SOLUTION: An aperture angle light ray 11 is emitted from a light emitting point P, is bent by a semispherical face 212a of a lens 212, and reaches an incident end face 180a at an angle θ3 equal to the aperture angle of a projection side optical fiber 180 with respect to an axis X2 parallel to an optical axis X. An outer edge light ray 12 is emitted from the light emitting point P, is passed through a lens 212, and reaches the outer edge part 184 of a core area 180b. The locations of a light emission face 162a, the lens 212 and the projection side optical fiber 180, and the refractive power of the lens are selected such that an angle θ3' at which the outer edge light ray 12 reaches the outer edge part 184 of the core area 180b is equal to or less than the aperture angle. <P>COPYRIGHT: (C)2013,JPO&INPIT |
