Profile measurement method for the inclination angle greater than ±30°
NH Series offers absolute accuracy measurements in less than ±0.1μm within ±30°of inclination angle. We adopted a stitching measurement technology described in the right figure for measuring high NA aspheric lens having greater inclination angle than ±30°.
It was difficult to evaluate sub-micrometer aspheric surface since the rotation accuracy and the rotation center position directly affect measurement error in the regular R-θmeasurement. However, this measurement technology solved these problems and offers high precision measurement up to ±90°.
