Abstract: BT combining an optical phase comparison method with a Zeemaa-laser, a high resolution heterodyne interference measurement system has been established. It can be used for direct measurement of the refractive index of sir The repeatibility of dm/was determined, In the great number of experiments with 5X10-8.

Key words: Grinding equipment, Grinding process, Precision grinding technology oriented to achieve high process efficiency, Research summary, Large and middle-scale optic