| 摘要 |
PURPOSE:To enable an accurate measurement of pressure without being affected by surrounding electric noise by changing the quality of light passing end faces of two optical fibers connected to a light emitting section and a light receiving/ measuring section interlocking the displacement of a pressure receiving plate. CONSTITUTION:An end face 3 of an optical fiber 2 connected to a light emitting section 1 and an end face 3' of an optical fiber 2' connected to a light receiving/ measuring section 4 are arranged opposite to each other at a space, inserted into a hollow cylindrical tube 6 at a pressure detector section 5 and a pressure receiving plate 8 is provided at the bottom thereof. As a pressure to be measured is applied on the pressure receiving plate 8, the pressure receiving plate moves upward so that a shielding plate 9 errected at the center thereof is inserted deep into the end surfaces 3 and 3'. A pressure is measured depending on the difference between the quantity of light passing the end faces 3 and 3' and the quantity of light fed directly to the light receiving section 4 through an optical fiber 10 from the light emitting section 1. This enables an accurate measurement of pressure without being affected by surrounding electric noises thereby eliminating errors in the measurement due to variations in the quality of light resulting from deterioration of the light emitting section 1. |
