[OPTICAL REVIEW Vol. 7, No. 2 (2000) 123-128]

Noise-Limitations of Coherence Imaging Based on Wavefront Folding Interferometry

Hidenobu ARIMOTO,1 Kyu YOSHIMORI2 and Kazuyoshi ITOH1

1Graduate School of Engineering, Department of Applied Physics, Osaka University, 2-1 Yamada-oka, Suita, Osaka, 565-0871 Japan, 2Earth Observation Research Center, National Space Development Agency of Japan, 1-1-9 Roppongi, Minatoku, Tokyo, 106-0032 Japan

(Received November 4, 1999; Accepted January 17, 2000)

Noise-limitations of the coherence imaging system based on the wavefront folding interferometer are studied. The signal-to-noise ratio SNR in two kinds of noise-limiting cases, the photon-noise-limit and the detector-noise-limit, is derived and are compared with the experimental results. The experimental demonstration is conducted using a wavefront folding interferometer and a single slit that provides the light source. An ensemble of ten sets of data are measured under the same conditions and the statistics of the retrieved images are computed from them. It is verified that the experimental results generally agree with the theoretical expectations.

Key words : coherence imaging, cross-spectral density, photon-noise-limit, detector-noise-limit, mass fractal, surface fractal, combined fractal, self-similarity, power law, fractal dimension