Linear moving meters designed on the basis of laser probing of scales of a type: Surface acoustic wave (SAW) - Diffraction grating (DG)

A comparative analysis of moving meters schemes of an acoustic-optical type is carried out. Reference scales formed by surface acoustic waves and diffraction gratings are used in these schemes. The system SAW-DG is probed by a laser beam. The measurement of movement is effected by change of the phase of a signal at SAW frequency in the optoelectronic channel. Repeatability, resolving power, exactitude, range of measurements are analyzed. The resolving power better than 0,05 microns can be reached using SAW wave-length in a range of 30 up to 100 microns.