Optical pressure measurement devices, methods, and systems

Patent metadata

Field	Value
Publication number	US-11920997-B2
Application number	US-202017439119-A
Country	US
Kind code	B2
Filing date	Mar 12, 2020
Priority date	Mar 15, 2019
Publication date	Mar 5, 2024
Grant date	Mar 5, 2024

Abstract

A pressure measurement system includes a pressure pod with two chambers separated by a diaphragm such that a deformation/movement of the diaphragm is indicative of a difference between the pressures of the two chambers. Such deformation/movement is detected by a device that has no physical contact with the diaphragm, for example, by an optical detector that detects a change in the shape of the diaphragm or a movement of a protrusion on the diaphragm.

First claim

What is claimed is:

1. A method of pressure measurement comprising:
determining a first Moire pattern resulting from an interference of a first Moire filter with markings on a diaphragm of a pressure pod;
determining a movement or deformation of the diaphragm based on the first Moire pattern;
determining a second Moire pattern resulting from an interference of a second Moire filter with markings on a protrusion on the diaphragm of the pressure pod;
determining a movement of the protrusion on the diaphragm based on the second Moire pattern; and
determining a fluid pressure in the pressure pod based on the movement or deformation of the diaphragm and the movement of the protrusion on the diaphragm.

2. The method of claim 1 , wherein the first Moire filter comprises concentric transparent and opaque circles.

3. The method of claim 1 , wherein the markings on the diaphragm comprise concentric transparent and opaque circles.

4. The method of claim 1 , wherein the markings on the diaphragm are engraved or embossed.

5. The method of claim 1 , wherein the second Moire filter comprises parallel transparent and opaque lines.

6. The method of claim 1 , wherein the markings on the protrusion on the diaphragm comprise parallel transparent and opaque lines.

7. The method of claim 1 , wherein the markings on the protrusion on the diaphragm are engraved or embossed.

Assignees

• Nxstage Medical Inc

Inventors

• Wyeth Mark T
• Brugger James M
• Mcdermott Adam G

Classifications

• G01L7/086 Primary

  with optical transmitting or indicating means · CPC title

• A61M1/3639

  Blood pressure control, pressure transducers specially adapted therefor · CPC title

• A61B5/02141 Primary

  Details of apparatus construction, e.g. pump units or housings therefor, cuff pressurising systems, arrangements of fluid conduits or circuits (A61B5/02233, A61B5/0235 take precedence) · CPC title

• A61B2562/0233

  Special features of optical sensors or probes classified in A61B5/00 · CPC title

• A61B2562/16

  Details of sensor housings or probes; Details of structural supports for sensors (A61B2560/0462 takes precedence) · CPC title