Superresolved optical scanning using polychromatic light

Subwavelength detection of object displacement with use of a polychromatic interferometric imaging system is demonstrated experimentally. Object position detection with 50-nm lateral resolution is achieved. This result derives from and is consistent with increases in information capacity with use of phase-sensitive polychromatic systems identified by Basinger et al. [J. Opt. Soc. Am. A 12, 704 (1995)]. This phase-sensitive polychromatic detection relies on an imaging interferometric cross-correlating receiver capable of 2-nm optical path difference resolution. © 1997 Optical Society of America.