| 摘要 |
PURPOSE:To adiust a detecting characteristic curve at any chosen setting, by locating a spacer for setting a distance between optical axes in free ends of light emitting and receiving sides to the desired length between free ends of an optical fiber. CONSTITUTION:A proximity sensor 1 is provided with light emitting side optical fiber 2 and light receiving side optical fiber 3, and one end 2a of the optical fiber 2 is connected with a light source 4 throwing parallel lights through a collimator lens, etc. One end 3a of the optical fiber 3 is connected with a photo- transistor 5, and an optical signal is converted to a corresponding electric signal. Other ends 2b, 3b are positioned in such a way that, optical axes are oriented parallel, and a spacer 6 is adjusted on its thickness and thus, the distance between optical axes of both optical fibers can be adjusted at any chosen value. A ray of light from the light emitting end 7 is incident to a specimen 9 and a part of the reflected light originated from it is in such an arrangement that, it enters into the optical fiber 3 from the light receiving end surface 8. |
