Fluid flow sensing apparatus for in vivo and industrial applications employing novel differential optical fiber pressure sensors

• US 5,178,153 A
• Filed: 09/13/1985
• Issued: 01/12/1993
• Est. Priority Date: 03/08/1984
• Status: Expired due to Fees

• Current Assignee: Optical Technologies Corporation
• Original Assignee: Optical Technologies Corporation
• Inventors: Einzig, Robert E.
• Primary Examiner(s): Pellegrino, Stephen C.
• Assistant Examiner(s): Shay, David
• Application Number:
  US06/776,118
• Time in Patent Office: 2,678 Days
• Field of Search: 128/637, 128/672, 128/673, 128/675, 128/691, 128/692, 128/663-667, 73/196, 73/861.42, 73/861.52, 73/861.61, 73/861.62, 73/705, 73/432 L, 356/345, 356/352
• US Class Current: 600/505
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• CPC Class Codes: A61B 5/6853 with a balloon
• CPC Class Codes: G01F 1/363 with electrical or electro-mechanical indication G01F1/37 and G01F1/38 take precedence
• CPC Class Codes: G01F 1/661 using light
• CPC Class Codes: G01L 11/025 using a pressure-sensitive optical fibre

Abstract

An optical fiber fluid flow device is provided for in vivo determination of blood flow in arteries. The device includes a fiber optical fluid pressure measuring device having at least first and second optical fiber sensors which optical fiber sensors are positioned in the blood passage and in a restricted flow area in the blood passage and the two fiber optical pressure fluid sensors are connected to an interferometer associated with an opto-electronic demodulator which has an output signal representing the differential pressure between the two sensed area. The device also has utility in industrial applications.

Claims

1. A fiber optic fluid pressure measuring device comprising a first optical fiber configured as a Fabry-Perot interferometer, a pressure responsive end on the first optical fiber, said pressure responsive end of said optical fiber including a first partial mirror and a mirrored end spaced therefrom, means positioning said responsive end in the fluid to be measured, a second optical fiber configured as a second Fabry-Perot interferometer, a pressure responsive end, said pressure responsive end of said second optical fiber including a first partial mirror and a mirrored end spaced therefrom, a constriction in the fluid to be measured spaced from the means positioning the first responsive end in the fluid to be measured, means positioning the second optical fiber responsive end in the fluid at the other side of the constriction, radiant energy emitting means for directing radiant energy to the interferometers and through their optical fiber responsive ends, and radiant energy detecting means connected to said interferometers.

2. Means for measuring fluid flow in arteries and veins comprising a catheter, fiber optic differential pressure measuring means housed in the catheter, said pressure measuring means comprising a first optical fiber configured as a first Fabry-Perot interferometer, a first fluid pressure responsive end on the first optical fiber, means mounting the first optical fiber responsive end in one end of the catheter, an enlarged zone formed on the catheter spaced from the first responsive end, a second optical fiber configured as a second Fabry-Perot interferometer, a second fluid pressure responsive end on the second optical fiber, means mounting the second pressure responsive end on the other side of said enlarged zone from the first responsive end, each of the optical fiber responsive ends including a first partial mirror and a mirrored end spaced therefrom, radiant energy emitting means for directing radiant energy to the interferometers, and through said first and second responsive ends, and radiant energy detecting means connected to said first and second interferometers.