APPARATUS AND METHOD FOR CONTROLLING RANGING DEPTH IN OPTICAL FREQUENCY DOMAIN IMAGING

• US 20080297806A1
• Filed: 01/18/2008
• Published: 12/04/2008
• Est. Priority Date: 01/19/2007
• Status: Active Grant

• Current Assignee: The General Hospital Corporation (Mass General Brigham, Inc.)
• Original Assignee: The General Hospital Corporation (Mass General Brigham, Inc.)
• Inventors: Bouma, Brett Eugene, Tearney, Guillermo J., Motaghiannezam, S.M. Reza
• Granted Patent: US 7,911,621 B2
• Time in Patent Office: Days
• US Class Current: 356/484
• CPC Class Codes: G01B 2290/70 Using polarization in the interferometer
• CPC Class Codes: G01B 9/02002 using two or more frequencies
• CPC Class Codes: G01B 9/02004 using frequency scans
• CPC Class Codes: G01B 9/02028 Two or more reference or object arms in one interferometer
• CPC Class Codes: G01B 9/02078 Caused by ambiguity
• CPC Class Codes: G01B 9/02091 Tomographic interferometers, e.g. based on optical coherence

Abstract

Exemplary embodiments of an apparatus are provided. For example, the exemplary apparatus can include at least one first arrangement providing at least one first electro-magnetic radiation to a sample, at least one second electro-magnetic radiation to a first reference and at least one third electro-magnetic radiation to a second reference. A frequency of radiation provided by the first arrangement generally varies over time. The exemplary apparatus may also include at least one second arrangement which is configured to detect a first interference between at least one fourth electro-magnetic radiation associated with the first electro-magnetic radiation and at least one fifth electro-magnetic radiation associated with the second radiation. The second arrangement is also configured to detect a second interference between at least one sixth electro-magnetic radiation associated with the first electro-magnetic radiation and at least one seventh electro-magnetic radiation associated with the third radiation.

Claims

1. An apparatus comprising:

at least one first arrangement providing at least one first electro-magnetic radiation to a sample, at least one second electro-magnetic radiation to a first reference and at least one third electro-magnetic radiation to a second reference, wherein a frequency of radiation provided by the at least one first arrangement varies over time; and

at least one second arrangement configured to detect;

(i) a first interference between at least one fourth electro-magnetic radiation associated with the at least one first electro-magnetic radiation and at least one fifth electro-magnetic radiation associated with the at least one second radiation, and

(ii) a second interference between at least one sixth electro-magnetic radiation associated with the at least one first electro-magnetic radiation and at least one seventh electro-magnetic radiation associated with the at least one third radiation.

2. The apparatus according to claim 1, wherein an optical path length of the first reference is substantially different from an optical path length of the second reference.

3. The apparatus according to claim 2, wherein the difference between the optical path length of the first reference and the optical path length of the second reference is more than 500 μ

m.

4. The apparatus according to claim 1, wherein the first reference has a further arrangement to shift a frequency of the at least one second electro-magnetic radiation.

5. The apparatus according to claim 4, wherein the first reference has an additional arrangement to shift a frequency of the at least one third electro-magnetic radiation.

6. The apparatus according to claim 4, wherein a magnitude of the shift of the frequency of the at least one second electro-magnetic radiation is different from a magnitude of the shift of the frequency of the at least one third electro-magnetic radiation.

7. The apparatus according to claim 1, wherein the at least one first electro-magnetic radiation has a spectrum whose mean frequency changes substantially continuously over time at a tuning speed that is greater than 100 Tera Hertz per millisecond.