The largest limitation of phase-shifting interferometry for optical testing is the sensitivity to the environment, both vibration and air turbulence. In many situations the measurement accuracy is limited by the environment and sometimes the environment is sufficiently bad that the measurement cannot be performed. Recently there have been several advances in dynamic interferometry techniques fo...

Phase-shifting digital holography is a digital measurement technology of a complex optical field profile that uses focal plane array detectors without the loss of bandwidth. It has been known that the accuracy of phase-shifting digital holography is limited mainly by the phase tolerance of reference. In this Letter, it is revealed that the uncertainty in an expected signal is highly dependent o...

Pay-for-performance (P4P) programs are expanding their purview from quality to include efficiency, and many consider the episode of care as the appropriate unit of measurement. Two years' experience by the California P4P program, however, reveals that the requisite claims data often are incomplete or poorly coded and that even large physician groups have too few patients experiencing most types...

This paper introduces an interferometric technique for the phase measurement of microwave devices. A handheld vector network analyzer (VNA) is presented for HF and VHF applications. A wideband synthesizer with multiple synchronized outputs is developed for extending the frequency range to the microwave band. The phase differences between the output signals can be set digitally with sub-degree a...

Hitherto no method, to our knowledge, was known to incorporate spatial phase shifting for the measurement of pure in-plane displacements. We demonstrate that the modified Duffy two-aperture configuration [Opt. Lett. 22, 1958 (1996)], which is sensitive to only the in-plane displacement component and offers increased sensitivity, lends itself to measurement with spatial phase shifting. The confi...

Fringe-projection profilometry is one of the most commonly used noncontact methods for acquiring the three-dimensional (3D) shape information of objects. In practice, the luminance nonlinearity caused by the gamma effect of a digital projector and a digital camera yields undesired fringe intensity changes, which substantially reduce the measurement accuracy. In this Letter, we present a robust ...

Three-dimensional shape measurement is used in various fields such as robotics and inspection of industry production. It is requested to measure shape with high speed and high accuracy. It is also requested to make the system compact and low-cost. It is, however, difficult to satisfy these requests simultaneously for 3D shape measurement. In order to measure shape in real-time, Kato et al. prop...

We study the nonlinearity (NL) in the conversion from charge to voltage in infrared detectors (HXRG) for use in precision astronomy. We present laboratory measurements of the NL function of a H2RG detector and discuss the accuracy to which it would need to be calibrated in future spacemissions to perform cosmologicalmeasurements through theweak gravitational lensing technique. In addition, we p...