| 摘要 |
PROBLEM TO BE SOLVED: To make decreasable the total reflection on the light receiving face and to make increasable the light guide efficiency by forming a lens in the light receiving part of a linear light guide which guides the received light. SOLUTION: The light from a LED 7 as an emission light source is introduced as much as possible to a light guide 11 and is effectively used. A mirror state slope 11b is formed on the end face in the longitudinal direction of the light guide body 11, while a convex lens 11a is formed as the light receiving part on the lower face of the end part along the longitudinal direction of the light guide 11 (made of an acrylic resin having, for example, 1.5 refractive index). The LED 7 housed in a container 12, having an aspheric lens 13 in the upper part is disposed under the light receiving part. The LED is disposed in the bottom of the container 12 and a funnel-like slope 12a is formed in the step 12b where the aspheric lens 13 is to be fixed. The surface of the funnel-like slope is formed into a mirror face so that the light from the LED is reflected and condensed to the aspheric lens 13. |
