| 摘要 |
PURPOSE:To obtain a detector which is easily moved and capable of detection at a narrow part by providing an optical waveguide which has a high-refractive- index part and a low-refractive-index part surrounding it and is formed thinly at part of the low-refractive-index part which is brought into contact with liquid. CONSTITUTION:The contact part 5 atop an optical fiber 2 is fixed so as to touch the surface of liquid 1 at specific height, and the fiber 2 forms one optical waveguide from a light source 3 to a photodetector 4. Then the fiber 2 has a core 21 which is high in refractive index at the center part and a clad 22 which is low in refractive index is formed surrounding the core; and the part 23 where the clad 22 is reduced in thickness to about 2-3mum is formed atop of a bent part. Consequently, while the contact part 5 does not touches the liquid 1, the quantity of light detected by the optical power meter of the photodetector 4 is -35.6dBm, but when the contact part 5 is brought into contact with the liquid 1, the detected quantity of light varies by >=+ or -10dBm, so the contacting of the contact part 5 with the liquid 1 is confirmed. |
