Claims
- 1. An optical system for monitoring or imaging a sample, comprising:
a probe having an optical fiber and a GRIN fiber-size lens fused to one end of the fiber; an optical splitter or circulator to receive light from a source and to direct a portion of the received light to the fiber; and an optical detector coupled to receive a portion of light collected from the sample by the GRIN fiber-size lens and to determine a characteristic of the sample from the received light.
- 2. The system of claim 1, wherein the GRIN fiber-size lens has a focal length of greater than 1 mm.
- 3. The system of claim 1, wherein the GRIN fiber-size lens has a rayleigh range that is greater than 200 microns.
- 4. The system of claim 3, wherein the GRIN fiber-size lens has a rayleigh range of at least 500 microns.
- 5. The system of claim 1, wherein the GRIN fiber-size lens does not have an integral outer optical cladding layer.
- 6. The system of claim 1, wherein a free end-face of the GRIN fiber-size lens is convexly rounded.
- 7. The system of claim 1, wherein the monitoring system comprises an optical interferometer having a measurement and reference arms, both arms being optically coupled to receive light from the splitter or circulator, the measurement arm including the probe.
- 8. The system of claim 7, further comprising:
an optical source coupled to transmit light to the measurement and reference arms and capable of producing light with a coherence length of less than 1 centimeter.
- 9. The system of claim 8, wherein one of the reference arm and the measurement arm has a variable optical path length.
- 10. A process for optically monitoring or imaging a sample, comprising:
directing light into an optical fiber; directing light from the fiber into a portion of the sample with a GRIN fiber-size lens; receiving light in the GRIN fiber-size lens in response to the received light being scattering or emitted by a region of the sample; and transmitting the received light to a detector.
- 11. The process of claim 10, further comprising:
determining one of a density, a depth, and a velocity of the portion of the sample based on the received light.
- 12. The process of claim 11, further comprising:
producing an image of the sample with data determined by the detector.
Parent Case Info
[0001] This application claims the benefit of U.S. Provisional Application No. 60/269,586, filed Feb. 17, 2001.
Provisional Applications (1)
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Number |
Date |
Country |
|
60269586 |
Feb 2001 |
US |