| 摘要 |
PURPOSE:To eliminate the need for recalibration in principle by widening and stabilizing a dynamic range mechanically by measuring oscillation by utilizing Doppler effect on laser light. CONSTITUTION:Laser light from a laser light source 19 is separated into light incident to an ultrasonic diffraction cell 20 through a beam splitter 22a, and light incident to an oscillation sensor part 16 through the beam splitter 22a, a lens 23b, an optical fiber 2a, a beam splitter 22b, and an optical fiber 2c. The light incident to the oscillation sensor part 16 is reflected by a mirror fitted to a weight in the oscillation sensor part 16. If an oscillation body 10 oscillates, the weight oscillates corresponding to the oscillation Doppler effect on incident light from the optical fiber 2c after being reflected by the said mirror is given in proportion to the oscillation speed of the weight to cause a frequency shift. This light and the primary diffracted light of the cell 20 are mixed by a beam splitter 22b to be guided to an optical receiver 24 through an optical fiber 2d, thus performing heterodyne detection. |
