Optical fiber pressure sensor

Abstract

The disclosure includes an apparatus for insertion into a body lumen. The apparatus can comprise an optical fiber pressure sensor. The optical fiber pressure sensor can comprise an optical fiber configured to transmit an optical sensing signal. A temperature compensated Fiber Bragg Grating (FBG) interferometer can be in optical communication with the optical fiber. The FBG interferometer can be configured to receive a pressure and modulate, in response to the received pressure, the optical sensing signal. A compliant member such as a sensor membrane can be in physical communication with the FBG interferometer. The membrane configured to transmit the received pressure to the FBG interferometer.

1 . (canceled) 
     
     
         2 . An optical pressure sensor assembly that is sized, shaped, or otherwise configured to be inserted into a human body to measure a pressure at an internal location within the human body, the assembly comprising:
 a housing including a proximal portion and a distal portion, the proximal portion and the distal portion separated by a window sensor portion;   an optical fiber extending through the housing, wherein the sensor assembly is positioned at a distal end of the optical fiber;   at least a first set of fiber Bragg gratings and a second set of fiber Bragg gratings included in the optical fiber,   wherein the first set of fiber Bragg gratings is positioned within the housing, and   wherein at least some of the fiber Bragg gratings of the second set of fiber Bragg gratings extend distally beyond a distal end of the housing.   
     
     
         3 . The assembly of  claim 2 , wherein the proximal portion includes a first material and window sensor portion includes a second material, and wherein the second material is different from the first material. 
     
     
         4 . The assembly of  claim 2 , wherein the at least the first set of fiber Bragg gratings and the second set of fiber Bragg gratings includes only those two sets of fiber Bragg gratings. 
     
     
         5 . The assembly of  claim 4 , wherein the first set of fiber Bragg gratings is configured to measure pressure and a first temperature, and the second set of fiber Bragg gratings is configured to measure a second temperature. 
     
     
         6 . The assembly of  claim 2 , wherein a portion of the optical fiber without fiber Bragg gratings is aligned with the window sensor portion. 
     
     
         7 . The assembly of  claim 2 , wherein the proximal end of the optical fiber is secured to the proximal portion at a proximal attachment region. 
     
     
         8 . The assembly of  claim 7 , wherein the proximal end of the optical fiber is secured by a tubular attachment. 
     
     
         9 . The assembly of  claim 2 , further including a third set of fiber Bragg gratings. 
     
     
         10 . The assembly of  claim 2 , wherein all of the fiber Bragg gratings of the second set of fiber Bragg gratings extend distally beyond a distal end of the housing. 
     
     
         11 . The assembly of  claim 9 , wherein at least some of the fiber Bragg gratings of the third set are aligned with the window sensor portion. 
     
     
         12 . The assembly of  claim 9 , wherein a first one of the sets of fiber Bragg gratings is configured to have a broadband response and a second one of the sets of fiber Bragg gratings is configured to have a narrowband response. 
     
     
         13 . The assembly of  claim 9 , wherein a first one of the sets of fiber Bragg gratings is configured to measure a first pressure, a second one of the sets of fiber Bragg gratings is configured to measure temperature, and a third one of the sets of fiber Bragg gratings is configured to measure a second pressure. 
     
     
         14 . The assembly of  claim 9 , further including a fourth set of fiber Bragg gratings. 
     
     
         15 . The assembly of  claim 14 , wherein a first one of the sets of fiber Bragg gratings is configured to measure a first pressure, a second one of the sets of fiber Bragg gratings is configured to measure a first temperature, a third one of the sets of fiber Bragg gratings is configured to measure a second pressure, and a fourth one of the sets of fiber Bragg gratings is configured to measure a second temperature. 
     
     
         16 . The assembly of  claim 2 , in combination with a guidewire. 
     
     
         17 . The assembly of  claim 16 , wherein the guidewire includes a solid core wire having an outer surface and a length, a portion of the outer surface defining a groove extending along a portion of the length of the core wire, the core wire including:
 a first portion having a first diameter and a second portion having a second diameter, wherein the second diameter is greater than the first diameter, and wherein the second portion defines a cradle sized and arranged to receive an optical fiber pressure sensor.   
     
     
         18 . The assembly of  claim 2 , wherein the fiber Bragg gratings of the second set of fiber Bragg gratings that extend distally beyond a distal end of the housing are configured to directly contact a bodily fluid. 
     
     
         19 . The assembly of  claim 2 , wherein all of the fiber Bragg gratings of the second set of fiber Bragg gratings extend distally beyond a distal end of the housing, and wherein the second set of fiber Bragg gratings is adjacent a distal end of the optical fiber. 
     
     
         20 . An optical pressure sensor assembly that is sized, shaped, or otherwise configured to be inserted into a human body to measure a pressure at an internal location within the human body, the assembly comprising:
 a housing including a proximal portion and a distal portion, the proximal portion and the distal portion separated by a window sensor portion, wherein the proximal portion includes a first material and window sensor portion includes a second material, and wherein the second material is different from the first material;   an optical fiber extending through the housing;   first and second interferometers in optical communication with the optical fiber,   wherein the first interferometer includes a first set of fiber Bragg gratings and the second interferometer includes the second set of fiber Bragg gratings.   
     
     
         21 . The assembly of  claim 20 , wherein at least one of the first interferometer and the second interferometer includes a phase-shift type interferometer. 
     
     
         22 . An optical pressure sensor assembly that is sized, shaped, or otherwise configured to be inserted into a human body to measure a pressure at an internal location within the human body, the assembly comprising:
 a housing including a proximal portion and a distal portion, the proximal portion and the distal portion separated by a window sensor portion;   an optical fiber extending through the housing;   first and second interferometers in optical communication with the optical fiber,   wherein the first interferometer includes a first set of fiber Bragg gratings and the second interferometer includes the second set of fiber Bragg gratings, and wherein at least some of the fiber Bragg gratings of the second set extend distally beyond a distal end of the housing and are configured to directly contact with a bodily fluid.