KY-039 Heartbeat Sensor Module [5V] package includes of the heartbeat sensor or finger pulse sensor module, which is based on a bright infrared LED and a phototransistor to sense and detect the heartbeat of the human finger.
This module should be isolated from external stray light receiving with the phototransistor to avoid noise, especially in home use, which is lighted with 50Hz or 60Hz lighting devices. This module is stable and precision response and can be used for DIY heartbeat projects and Arduino project development.
Uses bright infrared (IR) LED and a phototransistor to detect the pulse of the finger, a red LED flashes with each pulse.
Pulse monitor works as follows: The LED is the light side of the finger, and phototransistor on the other side of the finger, phototransistor used to obtain the flux emitted, when the blood pressure pulse by the finger when the resistance of the phototransistor will be slight changed.
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.
