| 摘要 |
PURPOSE:To measure the pressure and flow velocity in a fine part such as a blood vessel by using a polarization plane maintaining type optical fiber. CONSTITUTION:The clad 3 of the tip part of an optical fiber 1 for a sensor is cut as closely to the core 2 as possible and a half-mirror 4 which reflects a part of light is provided to the tip end surface of the optical fiber 1. A part of laser light transmitted through the optical fiber 1 is reflected by the mirror 4, transmitted through the core 2 again, and supplied to a reflected light intensity detector. In this case, the reflected light varies in intensity with pressure applied to the section 3a of the clad 3. The pressure applied to the section 3a is therefore detected. Further, when particles pass in front of the mirror 4, the laser light transmitted through the mirror 4 is reflected by the particle to have a Doppler shift and then supplied to the optical fiber 1, so the quantity of the Doppler shift which is the frequency difference between the reflected light and projected light is detected to measure the flow velocity of the particles at the same time. |
