Digital moire subtraction in optical engineering

Conventionally, for the most accurate measurements, interferometer systems are constructed from high-quality optical elements and include fine control s for precise alignment. In this alternative approach, all the errors of a poor quality, misaligned system are accepted then eliminated by a simple di gital moire process. The method offers the possibility of devising very lar ge aperture optical systems for traditional and engineering interferometers from inexpensive and basic components. It can also offer benefits in other measurement techniques, including moire. (C) 2001 Society of Photo-optical instrumentation Engineers.