Wafer Mapping
Through narrow Angular aperture (about 3 °), the interference caused by light diffusion can be avoided, so the detection with high positioning accuracy can be realized.

Measurement of wafer thickness after polishing
The thickness of the ground wafer is required to be uniform and flat, passing 0.001 μ The resolution of m can achieve ultra-high precision measurement. Stable measurement of thickness and flatness is achieved through a zero heating sensor probe.