Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Simple focal-length measurement technique with a circular Dammann grating

Journal Article · · Applied Optics
DOI:https://doi.org/10.1364/AO.46.000044· OSTI ID:20854005
A novel technique for focal-length measurements with a circular Dammann grating is presented. In the back focal plane of the lens under test, a one-order circular Dammann grating with limited aperture will produce double-humped radial rings. The separation between the two lobes varies with the displacement of the observed plane from the focal plane of the lens. By searching for the position at which the separation is minimal, the focal point of the lens can be located and hence the back focal length can be determined. Experimental results demonstrated that this method is efficient and can be used effectively for a quick check of focal length.
OSTI ID:
20854005
Journal Information:
Applied Optics, Journal Name: Applied Optics Journal Issue: 1 Vol. 46; ISSN 0003-6935; ISSN APOPAI
Country of Publication:
United States
Language:
English

Similar Records

Three-dimensional light trap for reflective particles
Patent · Thu Dec 31 23:00:00 EST 1998 · OSTI ID:872458

Three-dimensional light trap for reflective particles
Patent · Tue Aug 17 00:00:00 EDT 1999 · OSTI ID:678601

Three-dimensional profilometry using a Dammann grating
Journal Article · Wed Jul 01 00:00:00 EDT 2009 · Applied Optics · OSTI ID:22036387