Interferometer Setup The Twyman–Green interferometer (Figure 1) is a special configuration of the well-known Michelson interferometer with optics that superimpose the images of the object and the reference planes. Polytec engineers use this interferometer and place a CCD image sensor like those used for digital photography at the point where the two images are superimposed. A broadband “white-l...

While high-sensitivity moiré interferometry requires monochromatic light, an auxiliary compensator grating removes the requirement. Experimental verification utilized white light for moiré interference of sensitivity 0.833 microm/fringe. Configurations readily amenable to compensation include moiré fringe multiplication by even factors and the minimum-deviation arrangement. Chromatic compensati...

The last few years have seen major advances in laser interferometry. The use of laser diodes whose output wavelength can be controlled by varying the injection current has led to the development of several new techniques in interferometry, as well as new methods for multiplexing fiber-interferometer sensors. New fields have also been opened up by phase-conjugate interferometers and the use of s...

We study the phase sensitivity of SU(2) and SU(1,1) interferometers fed by two-mode field states which are intelligent states for Hermitian generators of the SU(2) and SU(1,1) groups, respectively. Intelligent states minimize uncertainty relations and this makes possible an essential reduction of the quantum noise in interferometers. Exact closed expressions for the minimum detectable phase shi...

The far-field patterns of atoms diffracted from a classical light field or quantum one in photon-number state are identical. On the other hand, diffraction coherent state, which shares many properties with light, displays completely different behavior. We show that contrast to patterns, interference signal an atom interferometer light-pulse beam splitters and mirrors intense states does approac...

Quality control is an important and integral part to any microfabrication process. While the widths of features often can be easily assessed by light microscopy, the heights of the fabricated structures are more difficult to determine. Here, we present a rapid, accurate, and low-cost method to measure the heights of microfabricated structures during and after the fabrication process. This techn...

Low coherence interferometry (LCI) is an optical technique in which light is used as an instrument to obtain high resolution optical images in a great diversity of materials. It is possible to find in the literature, a variety of configurations with different names, based on the same principle: low coherence reflectometry (OLCR), optical coherence tomography (OCT), white light interferometry (W...