Abstract

The dynamic signature of the subwavelength variation of a rectangular aperture has recently been shown to be determinable from far-field irradiance with a precision better than 1 nm [Opt. Lett. 29, 1045 (2004)]. We have proposed, and have theoretically shown, that detection sensitivity can be greatly enhanced with an embedded-aperture Mach–Zehnder interferometer configuration, after parameter optimization. The sensitivity, in terms of derivative intensity of observed subwavelength variations, could be enhanced approximately 2.7 times, compared with the directly detected method. Another method of detection of subwavelength variation from pattern measurement of far-field diffraction has also been proposed. The associated shifting of the dark line of the diffraction pattern had a good linear correlation to subwavelength variation, which was magnified approximately 150 times, and gave good contrast for measurement.

© 2005 Optical Society of America

Identifying the subwavelength-aperture-width variation in the far field with tunable asymmetrically-embedded-aperture interferometer configuration

Shu-Chun Chu and Jyh-Long Chern
J. Opt. Soc. Am. A 22(8) 1600-1606 (2005)

Detection of subwavelength slit-width variation with irradiance measurements in the far field

S. Selci and M. Righini
Opt. Lett. 27(22) 1971-1973 (2002)

Retrieving two-dimensional information of the subwavelength variation from far-field irradiance

Shu-Chun Chu and Jyh-Long Chern
J. Opt. Soc. Am. A 23(10) 2471-2475 (2006)

Characterization of the signature of subwavelength variation from far-field irradiance

Shu-Chun Chu and Jyh-Long Chern
Opt. Lett. 29(10) 1045-1047 (2004)

Far-field diffraction patterns of circular sectors and related apertures

Gonzalo Urcid and Alfonso Padilla
Appl. Opt. 44(36) 7677-7696 (2005)