Grating based phase control optical delay line
US6111645A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 15, 1998 |
| Grant date | Aug 29, 2000 |
| Priority date | — |
| Expiry date | May 15, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/141
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for performing high speed scanning of an optical delay and its application for performing optical interferometry, ranging, and imaging, including cross sectional imaging using optical coherence tomography, is disclosed. The apparatus achieves optical delay scanning by using diffractive optical elements in conjunction with imaging optics. In one embodiment a diffraction grating disperses an optical beam into different spectral frequency or wavelength components which are collimated by a lens. A mirror is placed one focal length away from the lens and the alteration of the grating groove density, the grating input angle, the grating output angle, and/or the mirror tilt produce a change in optical group and phase delay. This apparatus permits the optical group and phase delay to be scanned by scanning the angle of the mirror. In other embodiments, this device permits optical delay scanning without the use of moving parts.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.