| 摘要 |
PURPOSE:To provide low-loss and stable characteristics without cutting the optical fiber by etching part of the optical fiber then curving the fiber and letting high- refractive index liquid contact this curved part. CONSTITUTION:When a curved part 3 is provided after the clad layer 2 of an optical fiber is etched, the light signal passes through a beam locus 4 and propagates with virtually no losses. When the liquid 6 having a refractive index higher than that of the clad part 2 is contacted to the bent portion 3, the light is absorbed into the liquid 6 and the photo switch becomes OFF. Hence, the light signal passes through the beam locus 5 and becomes loss by entering the inside of the high refractive index liquid 6, thus it is not propagated beyond the bent portion 3. Hydrofluoric acid is effective for the etching solution of the optical fiber and since the optical fiber is not cut, the losses are substantially low. |
