Geophysical applications of radar interferometry to measure changes in the Earth's surface have exploded in the early 1990s. This new geodetic technique calculates the interference pattern caused by the difference in phase between two images acquired by a spaceborne synthetic aperture radar at two distinct times. The resulting interferogram is a contour map of the change in distance between the...

The rapidly developing fields of Micro-Electro Mechanical System (MEMS) and micro optics require non contact and high precision measurements. Optical profilers are ideally suited for this. Monochromatic Phase Shifting Interferometry(PSI) can be used to measure slowly varying profiles and step height of less than half a wavelength. White light interferometry is used when large step height are to...

We have studied a method to obtain both three-dimensional (3-D) spatial information and spectral information of a usual polychromatic object simultaneously by making use of a specifically designed two-wavefront folding interferometer and signal processing, including synthetic aperture technique, spectral decomposition, and 3-D image retrieval. The method uses only interferometric techniques and...

An innovative iterative search method called the synthetic phase-shifting (SPS) algorithm is proposed. This search algorithm is used for maximum-likelihood (ML) estimation of a wavefront that is described by a finite set of Zernike Fringe polynomials. In this paper, we estimate the coefficient, or parameter, values of the wavefront using a single interferogram obtained from a point-diffraction ...

The dispersion of the optimal estimate of a subsidence motion is determined, and compared with that of Permanent Scatterers, when the targets are progressively decorrelating due to Brownian motion. Approximately, with N consecutive images and revisit time T, the interferogram stack results are equivalent to PS's, if the pixel count in the window grows with N2T, independently of the frequency. I...

This paper proposes SAR imaging algorithm with largest coherence based on the existing SAR imaging algorithm. The basic idea of SAR imaging algorithm in imaging processing is that output signal can have maximum signal-to-noise ratio (SNR) by using the optimal imaging parameters. Traditional imaging algorithm can acquire the best focusing effect, but would bring the decoherence phenomenon in sub...