Novel Image Polarization Method for Measurement of Lens Decentration.

Tilt and decenter errors in lenses are usually caused by lens manufacturing processes: either injection or glass molding. This paper presents an image polarization method for measuring tilting and decentering of lenses. We placed a sample lens between two linear polarizers and passed either a focused or a divergent polarized beam through a half-wave or a full-wave plate. If any error were present in the shape of the lens, patterns and colors shown in the image of polarization would be altered. Finally, the degree of error in the shape of the lens can be computed using image processing software. [ABSTRACT FROM AUTHOR]