High resolution interferometric optical frequency domain reflectometry (OFDR) beyond the laser coherence length
AssigneeLuna Innovations Incorporated
InventorsMark Froggatt, Ryan J. Seeley, Dawn K. Gifford
Life of this patent
Estimating the term…
Abstract
The technology described here enables the use of an inexpensive laser to measure an interferometric response of an optical device under test (DUT) at reflection lengths significantly greater than the coherence length of the laser. This is particularly beneficial in practical interferometric applications where cost is a concern. In other words, inexpensive lasers having shorter coherence lengths may be used to achieve very high interferometric measurements at longer DUT reflection lengths. The technology also enables the use of such inexpensive lasers to measure Rayleigh scatter in commercial-grade, single-mode optical fiber.
Claims30
A method for interferometrically measuring an optical device under test (DUT), comprising:
- scanning the optical device under test by varying a wavelength of light generated by a laser, the laser having a corresponding coherence length, and
- determining an interferometric response of the optical device under test to the laser scanning,
- wherein the optical device under test has an associated optical length greater than the coherence length of the laser.
Apparatus for interferometrically measuring an optical device under test (DUT), comprising:
- a laser for scanning the optical device under test over a range of different wavelengths of light, the laser having a corresponding coherence length, and
- electronic circuitry that determines an interferometric response of the optical device under test to the laser scanning,
- wherein the interferometric response of the optical device under test has an associated optical length greater than the coherence length of the laser.
Dependencies are inferred from the claim text.