Real-time phasefront detector for heterodyne interferometers

TL;DR

This paper introduces a real-time, high-precision phasefront detector for heterodyne interferometers, capable of spatially resolving phasefronts at frequencies up to 10 kHz, aiding in optical metrology and space instrument manufacturing.

Contribution

The paper presents a novel real-time phasefront detector with sub-milliradian sensitivity, specifically designed for heterodyne interferometers used in space technology.

Findings

Sensitivity better than 3 mrad rms

Spatially resolving phasefront measurement up to 10 kHz

Applicable to optical metrology and space interferometry

Abstract

We present a real-time differential phasefront detector sensitive to better than 3 mrad rms, which corresponds to a precision of about 500 pm. This detector performs a spatially resolving measurement of the phasefront of a heterodyne interferometer, with heterodyne frequencies up to approximately 10 kHz. This instrument was developed as part of the research for the LISA Technology Package (LTP) interferometer, and will assist in the manufacture of its flight model. Due to the advantages this instrument offers, it also has general applications in optical metrology.