| 摘要 |
PURPOSE:To simplify the constitution and to improve the measurement precision by charging transparent liquid in two cup members which are sealed with diaphragms, detecting the operation of the diaphragm through an optical fiber, and obtaining the displacement signal of the diaphragm. CONSTITUTION:A detection part 2 has the cut members 6 and 7 where the transparent fluid is charged in internal chambers 6a and 7a sealed with the diaphragms 6 and 7 for lateral pressure and those internal chambers 6a and 7a are linked with each other through a capillary tube 8. Then, the operation of the diaphragms 4 and 5 is detected as variation in the quantity of reflected light through the optical fiber 10 arranged inside the cup members 6 and 7. The detected quantities of light are converted by photodetectors 17 and 18 into electric signals, whose difference is calculated by a differential amplifier 19 and led out as a differential pressure signal. Therefore, the displacement of the diaphragms 4 and 5 applied with high pressure and low pressure is led out directly without using any diaphragm for differential pressure measurement, so the high-precision differential pressure measurement is easily performed. |
