2018 Volume 62 Issue 3 Pages 141-147
Optical probes can measure specimen profiles under perfectly non-contact conditions, and have high vertical resolution. Therefore, optical probes are widely used for profile measurement. However, optical probes have the drawback of low lateral resolution. The lateral resolution of an optical probe depends on the spot size of the laser at the measurement point, and is generally one order of magnitude lower than the vertical resolution. This study proposes an optical probe with high lateral resolution by collecting laser irradiation. In addition, profile measurement simulations using a ray tracing method were performed. Simulation results confirmed that the displacement and tilt information of the specimen could be obtained from the outputs of the right and left optical probes. Furthermore, the results of profile measurement simulation showed that the lateral resolution in profile measurement can be improved by the proposed optical probe.
