Phoenix Ambulatory Blood Pressure Monitor Project
Sub-project: OptoElectronic Sensor, Phoenix Project team

Project Description

The purposes of the OptoElectronic Sensor project are to develop a pair of opto-electronic sensors that 

• produce a signal that shows the pulse wave clearly enough to use on the Data Acquisition Prototype, and
• can be used to test the usefulness of the Chen patent.

Project Deliverables

Sensors, Detection circuit, Amplification circuit, Filter circuit

Project Report

In the first phase, we are building a simple circuit based on

• Optek Technology OP140A GaAs Plastic Infrared Emitting Diode (Spec Sheet at http://www.optekinc.com/datasheets/OP140.PDF)
• Optek Technology OP550A Silicon Phototransistor (Spec Sheet at http://www.optekinc.com/datasheets/OP550A.pdf) and
• the schematic on p. 22 of this paper: http://dspace.mit.edu/handle/1721.1/33121 (also at http://hdl.handle.net/1721.1/33121, download the  paper at http://dspace.mit.edu/bitstream/handle/1721.1/33121/62239232.pdf?sequence=1)

The first attempt to record a pulse wave from a lab member's finger looks like the following:


This image appears to show systole and the dicrotic notch, but not diastole.  The signal is being captured raw with a digital oscilloscope and has no amplification or filtering applied.  We have yet to experiment with placing the sensor on wrist or arm, or look at any software signal processing.

Lab Notes

20091121

Work in 2011

A new PCB was designed, with the intent of being more stable than the original breadboard circuit and solid connectors for the sensors. 
Bill Of Materials
Schematic
PCB Layout
Design Files

Volunteers Are Needed

Would you like to work on any part of this project?  Envision a prototype, propose a way to implement it, and send your suggestion to Larry.  Or start out by just asking questions.

About This Page

This page is maintained by Larry A. Beaty.  It was last updated on 28 January 2012.

The author(s) provide this information as a public service, and agree to place any novel and useful inventions disclosed herein into the public domain. They are not aware that this material infringes on the patent, copyright, trademark or trade secret rights of others. However, there is a possibility that such infringement may exist without their knowledge. The user assumes all responsibility for determining if this information infringes on the intellectual property rights of others before applying it to products or services.

(C) 2011 Larry A. Beaty, Garrett Heidorn. Copying and distribution of this page is permitted in any medium, provided this notice is preserved.

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