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DIY photoplethysmographic pulse sensor

Posted on Wednesday, September 19th, 2012 in DIY, sensors by the machinegeek


Raj has posted a tutorial about a DIY photoplethysmographic sensor for measuring heart rate from fingertip. “The sensor measures the little variations in the blood volume inside finger tissue and outputs a digital pulse which is synchronous with the heart beat.” The sensor used in this project is TCRT1000, which is a reflective optical sensor with both the infrared light emitter and phototransistor. The sensors output goes through several stages of signal conditioning using a MCP6004 op amp before its fed into an oscilloscope or similar device.

You can find the schemtic and other project info in Raj’s post on EmbeddedLab.

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This entry was posted on Wednesday, September 19th, 2012 at 4:10 pm and is filed under DIY, sensors. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.

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