A Fujitsu research lab has developed software that can accurately measure a subject’s pulse using the small digital cameras attached to smartphones and tablets.
The technology is based on the fact that the brightness of an individual’s face changes slightly as their heart beats, due to their blood flow. Hemoglobin, which carries oxygen around the body, absorbs green light, so analyzing the change in color of parts of the face reveals their heart rate.
As most image sensors capture pixel information in red, blue and green, they have the ability to detect hemoglobin built in. Fujitsu’s technology keeps track of specific regions of the face over time to take pulse measurements.