Optical coherence tomography with graded index fiber for biological imaging

• US 9,557,156 B2
• Filed: 03/15/2013
• Issued: 01/31/2017
• Est. Priority Date: 05/14/2012
• Status: Active Grant

• Current Assignee: Avinger Inc.
• Original Assignee: Avinger Inc.
• Inventors: Kankaria, Manish
• Primary Examiner(s): REMALY, MARK DONALD
• Application Number:
  US14/400,140
• Publication Number:
  US 20150099984A1
• Time in Patent Office: 1,418 Days
• US Class Current: 1/1
• CPC Class Codes: A61B 17/3207 Atherectomy devices working by cutting or abrading; Similar devices specially adapted for non-vascular obstructions A61B17/32037 takes precedence; endoscopic cutting instruments A61B17/320016
• CPC Class Codes: A61B 2017/00057 Light
• CPC Class Codes: A61B 2017/22094 for crossing total occlusions, i.e. piercing
• CPC Class Codes: A61B 2562/0233 Special features of optical sensors or probes classified in A61B5/00
• CPC Class Codes: A61B 5/0066 Optical coherence imaging
• CPC Class Codes: A61B 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• CPC Class Codes: A61B 5/6852 Catheters
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: A61M 25/09 Guide wires
• CPC Class Codes: G01B 9/0205 of probe head
• CPC Class Codes: G01B 9/02057 by using common path configuration, i.e. reference and object path almost entirely overlapping
• CPC Class Codes: G01B 9/02091 Tomographic interferometers, e.g. based on optical coherence
• CPC Class Codes: G02B 6/028 with core or cladding having graded refractive index G02B6/02033, G02B6/02295 take precedence
• CPC Class Codes: G02B 6/25 Preparing the ends of light guides for coupling, e.g. cutting
• CPC Class Codes: G02B 6/255 Splicing of light guides, e.g. by fusion or bonding
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

A system for optical coherence tomography includes a source of optical radiation, an optical fiber, and a graded index fiber attached to a distal end of the optical fiber. The optical fiber and the graded index fiber are together configured to provide a common path for optical radiation reflected from a reference interface at a distal end of the graded index fiber and from a target.

Claims

1. A system for optical coherence tomography, comprising:

a source of optical radiation;

an optical fiber;

a graded index fiber attached to a distal end of the optical fiber, wherein the optical fiber and the graded index fiber are together configured to provide a common path for optical radiation reflected from a reference interface at a distal end of the graded index fiber and from a target;

receiving electronics configured to receive the optical radiation reflected from the reference interface and the target; and

a processor to generate an image of the target based upon the optical radiation received by the receiving electronics.

2. The system of claim 1, wherein a secondary reflection of optical radiation from an interface between the optical fiber and the graded index fiber is less than −

60 dB.

3. The system of claim 1, wherein the reference interface provides a reference reflection of between −

28 and −

42 dB.

4. The system of claim 1, further comprising an interface medium at the reference interface and in optical contact with the graded index fiber.

5. The system of claim 4, wherein a refractive index of the graded index fiber and a refractive index of the reference medium are mismatched such that the receiving electronics operate in a total noise range that is within 5 dB of the shot noise limit.

6. The system of claim 4, wherein the reference interface is angled with respect to a longitudinal axis of the graded index fiber such the receiving electronics operate in a total noise range that is within 5 dB of the shot noise limit.

7. The system of claim 4, wherein a surface of the interface medium that is closest to the target is concave.

8. The system of claim 4, wherein the interface medium is an adhesive.

9. The system of claim 1, wherein an outer diameter of the graded index fiber and a protective coating around the graded index fiber is less than 0.01 inches.

10. A system for optical coherence tomography, comprising:

a source of optical radiation;

an optical fiber;

a graded index fiber attached to a distal end of the optical fiber, wherein the optical fiber and the graded index fiber are together configured to provide a common path for optical radiation reflected from a reference interface at a distal end of the graded index fiber and from a target;

receiving electronics configured to receive the optical radiation reflected from the reference interface and the target; and

a processor to generate an image of the target based upon the optical radiation received by the receiving electronics;

wherein a secondary reflection of optical radiation from an interface between the optical fiber and the graded index fiber is less than −

60 dB.

11. The system of claim 10, wherein the reference interface provides a reference reflection of between −

28 and −

42 dB.

12. The system of claim 10, further comprising an interface medium at the reference interface and in optical contact with the graded index fiber.

13. The system of claim 12, wherein a refractive index of the graded index fiber and a refractive index of the reference medium are mismatched such that the receiving electronics operate in a total noise range that is within 5 dB of the shot noise limit.

14. The system of claim 12, wherein the reference interface is angled with respect to a longitudinal axis of the graded index fiber such the receiving electronics operate in a total noise range that is within 5 dB of the shot noise limit.

15. The system of claim 12, wherein a surface of the interface medium that is closest to the target is concave.

16. The system of claim 12, wherein the interface medium is an adhesive.

17. The system of claim 10, wherein an outer diameter of the graded index fiber and a protective coating around the graded index fiber is less than 0.01 inches.