Abstract

Using a modified Mach–Zehnder interferometer for electromagnetic 3-cm waves, we measured the amplitude and phase distributions in the diffraction near fields of dielectric bars with rectangular cross sections (sizes smaller than 1 square wavelength, λ) with high spatial resolution. Computer-controlled measurements were performed with high accuracy for distances 0.1λ–2λ behind the rear of the weak phase objects (phase shift Δφ ≪ 1 rad) that consist of foam materials (refractive index n = 1.02) or of thin plastic strips (n = 1.65, thickness d ≪ λ). The experimental results agree with field computations made with the moment method.

© 1991 Optical Society of America

Validity of the scalar Kirchhoff and Rayleigh–Sommerfeld diffraction theories in the near field of small phase objects

M. Totzeck
J. Opt. Soc. Am. A 8(1) 27-32 (1991)

Structure determination of weak phase objects from interferometric near-field measurements

Marco A. Krumbügel and Michael Totzeck
Appl. Opt. 33(34) 7864-7874 (1994)

Extension of Babinet’s principle and the Andrews boundary diffraction wave to weak phase objects

Michael Totzeck and Marco A. Krumbügel
J. Opt. Soc. Am. A 11(12) 3235-3240 (1994)

Polarization- and thickness-dependent near fields of small phase-shifting structures

Michael Totzeck
Appl. Opt. 32(11) 1901-1910 (1993)

Scattering by a small object close to an interface. II. Study of backscattering

K. O. Muinonen, A. H. Sihvola, I. V. Lindell, and K. A. Lumme
J. Opt. Soc. Am. A 8(3) 477-482 (1991)