We present a noise estimation and subtraction algorithm capable of increasing the sensitivity heterodyne laser interferometers by one order magnitude. The interferometer is specially designed for dynamic measurements test mass in application sub-Hz inertial sensing. A floor 3.31×10−11m/Hz at 100 mHz achieved after applying our to benchtop prototype that showed level 2.76×10−10m/Hz when tested v...

Abstract The high-precision phase extraction method directly determines the final measurement performance of heterodyne laser interferometer. This paper proposes a digital quadrature phase-locked (DQPL) with sub-nanometer precision based on FPGA hardware and compiled LABVIEW platform. DQPL can accurately extract difference two optical signals in validity stability have been verified by simulati...

The measurement of small displacements on the nanometric scale demands metrological systems of high accuracy and precision. In this context, interferometer-based displacement measurements have become the main tools used for traceable dimensional metrology. The different industrial applications in which small displacement measurements are employed requires the use of online measurements, high sp...

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...

Abstract The interferometer of the LISA technology package (LTP) on SMART-2 is needed to verify the performance of the gravitational sensors by monitoring the distance between two test masses with a noise level of 10 pm Hz−1/2 between 3 mHz and 30 mHz. It must continuously track the motion of the test mass distance while that distance changes by many μm with a speed of up to 20 μm s−1, without ...