Abstract This paper describes a standing-wave interferometer with two laser sources of different wavelengths, diametrically opposed and emitting towards each other. The resulting standing wave has an intensity profile which is moving constant velocity, directly detected inside the beam by thin transparent photo sensors. first sensor at fixed position, serving as phase reference for second one m...

The Infrared Spatial Interferometer (ISI) is a three telescope interferometer system that operates near 11 microns wavelength using heterodyne detection with CO2 lasers as local oscillators. Stellar measurements have been made using consistent instrumentation for 20 years, allowing comparisons of stellar sizes of red giant and Mira stars over time intervals which are long in comparison to stell...

Periodic nonlinearity (PNL) in displacement interferometers is a systematic error source that limits measurement accuracy. The PNL of coaxial heterodyne interferometers is highly influenced by the polarization state and orientation of the source frequencies. In this Letter, we investigate this error source and discuss two interferometer designs, designed at TU Delft, that showed very low levels...

We describe the realization of a phase-sensitive and ultrafast near-field microscope, optimized for investigation of surface plasmon polariton propagation. The apparatus consists of a homebuilt near-field microscope that is incorporated in Mach-Zehnder-type interferometer which enables heterodyne detection. We show that this microscope is able to measure dynamical properties of both photonic an...

Single longitudinal mode (SLM) erbium-doped fiber (EDF) laser operation using a commercialized ultra-narrow bandwidth optical filter has been studied. A two-meter long EDF with an absorption coefficient of 24 dBm at the pump wavelength is used as gain medium. The ultra-narrow tunable filter is used for selection of a single longitudinal mode from the available spectrum of multiple modes, which ...

In this study, we developed an automated, multipoint primary accelerometer calibration system using a two-axis positioning stage and heterodyne laser interferometer. The proposed offers low-cost, convenient, automated calibration, enabling less lead time. also better repeatability of 1μm, which is impossible through manual alignments. We measured the surface deformation reflection adaptor for s...

We describe a balanced heterodyne detection method for a Sagnac interferometer that uses a polarization-dependent beam splitter. The signal and the local oscillator are orthogonally polarized components of a single laser beam, permitting the detection of the signal by subtraction of two photocurrents produced in appropriate polarization projections. Using this scheme, we experimentally demonstr...