| 摘要 |
PURPOSE:To measure the pressure accurately by providing an arithmetic means which eliminates a change of the quantity of light by a disturbance from the outputs of the 1st photosensitive element and the 2nd photosensitive element and an output adjusting means which makes a linear relation of an output signal of the arithmetic means with the pressure receiving force. CONSTITUTION:When an oscillation by the external force, namely, the disturbance occurs on optical fibers 5, 7 and 13, the quantity of reflected light from the reflecting surface 1a is made betaalphaI. The quantity of rays for reference passing through the optical fiber 13 for reference at this time is made betaI. Then, the 1st photosensitive element 9a receives the quantity of light betaalphaI from the optical fiber 7 for photodetection and converts this into an electrical signal, for instance, alphaE (on condition that E=betaI) which is inputted to the arithmetic means 15. A dividing calculation of Ealpha/E=alpha is performed from these signals Ealpha and E with the arithmetic means 15. Since a result alpha of the dividing calculation with the arithmetic means 15 is a rate of change of the quantity of rays I according to the pressure P received by a pressure receiving diaphragm 1, a factor of a change of the quantity of light by the disturbance is eliminated. The linear relation of the pressure receiving force P is made with the output adjusting means based on the value alpha to measure the pressure accurately.
|
