Optimization of Fabrication Process of an Optical Element

Abstract

A new method of evaluating optical elements is proposed for use in optimization of the optical element fabrication process by quality engineering, In the past,such evaluations have usually been carried out by evaluating quality characteristics such as shape, but this has been difficult because of the high precision required in the optical elements. The new evaluation method evaluates the transferability of a light spot obtained by focusing the exit light of the optical element with a lens. The proposed idea is to compare the shapes of the focused light spots of the mold and the molded product, the ideal condition being no change in the shape of the spot. The signal factor was the shape of the focused light spot from the mold. To introduce noise factors, comparisons were made in both the central region of best transferability and peripheral regions of poor transferability, taking profiles in both the x- and y-directions. From the experimental results, it was possible to tell what factors were important for raising the S/N ratio (for reducing variability). The authors are unaware of previous examples of this type of functional evaluation.