Apparatus and method for producing rapid and accurate laser phase shifts
US10642075B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 27, 2017 |
| Grant date | May 5, 2020 |
| Priority date | — |
| Expiry date | Dec 29, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S3/1305
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A phase controller for rapid, accurate, stable phase shifting of a continuous wave (cw) laser output combines and adjusts reference paths from before and after an EOPM to obtain maximum constructive interference when the EOPM control voltage is zero. A control voltage V for maximum destructive interference is then determined and regulated to produce and maintain a 180 degree phase shift. The output phase can then be shifted by switching the control voltage to the output of a voltage shifter that shifts V by a specified percentage. The phase shifter can divide the control voltage in half to provide a 90 degree phase shift. The cw laser can function as a seed to a pulsed laser, thereby controlling the pulse phases. Quadrature phase laser pulse pairs can be used for quadrature LiDAR detection. Embodiments include a plurality of voltage shifters for 4-phase quadrature shifting and/or shifting between arbitrary phase values.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.