Quick Overview

• Use IR LED and an optical transistor to detect pulsation in fingers
• Small and Compact module
• Easy to use.

Product Description

        This KY-039 Finger Detection Heartbeat Measuring Sensor Module uses bright infrared (IR) LED and a phototransistor to detect the pulse of the finger, a red LED flashes with each pulse.

We chose a very high resistance resistor R1 because most of the light through the finger is absorbed, it is desirable that the phototransistor is sensitive enough. Resistance can be selected by experiment to get the best results. The most important is to keep the shield stray light into the phototransistor.

For home lighting that is particularly important because the lights at home mostly based 50HZ or 60HZ fluctuate, so faint heartbeat will add considerable noise.