Self-referencing Mach-Zehnder interferometer
US4637725A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 1985 |
| Grant date | Jan 20, 1987 |
| Priority date | — |
| Expiry date | Sep 26, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2290/10
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An interferometer in Mach-Zehnder configuration comprises beamsplitters (10, 12) and mirrors (11, 13), which divide an optical beam whose wavefront is to be monitored into an information component and a reference component, and which recombine the information and reference components to form an interference pattern that changes dynamically at a spatial light modulator (14) in response to dynamic variations in the atmosphere through which the beam passes. A spatial light filter (15) comprising a plate with a pin-hole aperture is positioned to transmit the reference component of the beam, but with second-order aberrations being removed from the reference component prior to recombination of the information and reference components. The wavefront of the reference component that recombines with the information component is a substantially unaberrated version of the wavefront of the beam whose wavefront is to be monitored. An acousto-optical beam-steering device (20) steers the reference component in real time so as to maintain substantially continuous alignment of a maximum-intensity centroid of the reference component with respect to the pin-hole aperture of the spatial light filter (1…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.