Optoprofiler LLC - Opto-Caliper Probe
This is a compact probe enabling absolute distance

Our Opto-Caliper prob can be integrated with cables of arbitrary
length with significant improvement over Echoprobe and
Michelson Interferometer solutions.

Hight warp and wafer curvature options are available. Solution
can be provided in single, dual probe, and multiprobe version.
Dual probe version can be implemented for nontransparent
wafers and slab metrology.
Raw Signal
Optical Thickness and Distance Probe Specifications