Ambient light sensor for heart rate sensing in wearables
Everlight (New Taipei City, Taiwan) has introduced an ambient light sensor that operates at 550nm with a very low signal calculation failure rate and a high current efficiency. An anticipated application for this device is heart rate signal detection in wearable electronics for the health and fitness sector. by Graham Prophet @ edn-europe.com:
Based on the principle of PPG (photoplethysmogram), the heart rate signal is calculated according to the current changes in transmission and reflection between a green light LED and the sensor to detect the systolic and diastolic blood vessel rythym. With a large detection area of 8.1mm ², improved signal strength is available from the ALS-PD50-42C. The larger sensing area can also improve the capabilities in instances when there are signal interferences caused by people’s skin colour, tattoos and hair on the skin.
Ambient light sensor for heart rate sensing in wearables – [Link]