Low-complexity optical force sensor for a medical device

• US 9,999,479 B2
• Filed: 06/17/2016
• Issued: 06/19/2018
• Est. Priority Date: 01/29/2013
• Status: Active Grant

• Current Assignee: St. Jude Medical (Abbott Laboratories Incorporated)
• Original Assignee: ST JUDE MEDICAL INTERNATIONAL HOLDING S. R.L.
• Inventors: Klimovitch, Gleb V.
• Primary Examiner(s): Pyo, Kevin
• Application Number:
  US15/185,285
• Publication Number:
  US 20160367330A1
• Time in Patent Office: 732 Days
• CPC Class Codes: A61B 2090/065 for measuring contact or contact pressure
• CPC Class Codes: A61B 90/06 Measuring instruments not otherwise provided for
• CPC Class Codes: A61M 2025/0002 with a pressure sensor at the distal end
• CPC Class Codes: G01B 11/16 for measuring the deformation in a solid, e.g. optical strain gauge
• CPC Class Codes: G01L 1/24 by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet
• CPC Class Codes: G01L 5/0028 Force sensors associated with force applying means G01L5/0052, G01L5/0057, G01L5/0061 take precedence

Abstract

An apparatus for detecting deformation of an elongate body may comprise a light source configured to sequentially provide light of multiple frequencies, an optical receiver configured to receive light from the light source, and a filter disposed between the light source and the optical detector. The filter may comprise multiple segments, each of the segments configured to filter light at one of the frequencies so as to alter the amount of light incident on said optical receiver. A total amount of light detected by the optical receiver may change during the sequence so as to be indicative of deformation of the elongate body.

Claims

1. A system for assessing force on a medical device, the system comprising:

an electronic control unit (ECU) configured to;

couple to a medical device;

operate a light source to emit light in a predetermined sequence, said sequence comprising two or more time segments;

receive a signal generated by an optical receiver responsive to said light output by said light source; and

process said signal in accordance with said predetermined sequence to determine an external force applied to the medical device and a magnitude and direction of a twisting of the medical device.

2. The system of claim 1, wherein

a filter is disposed between said light source and said optical receiver, said filter comprising multiple segments, at least two of said multiple segments configured to filter light at a different frequency so as to alter the amount of light incident on said optical receiver, wherein said optical receiver is configured to receive light from all of the multiple segments of the filter;

and

wherein a total amount of light received by said optical receiver is indicative of deformation of the elongate body.

3. The system of claim 2, wherein said filter comprises a first number of segments, said light source is configured to provide light of a second number of frequencies, and said first number is greater than or equal to said second number.

4. The system of claim 3, wherein said filter comprises at least four segments.

5. The system of claim 1, wherein said light source comprises a mechanically-single light source.

6. The system of claim 5, wherein said light source comprises a multi-color LED.

7. The system of claim 2, wherein the light source is configured to output a non-circular projection on the filter.

8. The system of claim 1, wherein the medical device comprises:

a handle; and

an elongate shaft having a proximal end portion and a distal end portion, said proximal end portion coupled with said handle, said elongate shaft configured for insertion into a body of a patient;

wherein said light source is configured to provide light along an optical path, said optical path disposed at least in part within said distal end portion of said elongate shaft and contained completely within the medical device; and

wherein said optical receiver is configured to receive light projected along said optical path.

9. The system of claim 8, wherein said light source and said optical receiver are disposed in said distal end portion of said shaft.

10. The system of claim 9, wherein said light source is disposed about 0.5 inches to about 2.0 inches from said optical receiver.

11. The system of claim 8, wherein said optical path is sealed from fluid.

12. The system of claim 8, wherein at least one of said light source and said optical receiver is disposed within about two inches of a distal tip of said shaft.

13. The system of claim 1, wherein said ECU is configured to process said signal in accordance with said predetermined sequence to determine a magnitude and a direction of a deflection of the medical device.

14. The system of claim 1, wherein said ECU is configured to process said signal in accordance with said predetermined sequence by determining an amount of light received by said optical detector at multiple different segments of said sequence.

15. The system of claim 1, wherein said light source is configured to provide light of multiple frequencies.

16. The system of claim 1, wherein two of said time segments have different respective durations.

17. The system of claim 1, wherein said ECU is configured to process said signal in accordance with said predetermined sequence to determine a magnitude and a direction of said external force.

18. The system of claim 15, wherein light of all of said multiple frequencies is in the visible spectrum.