12 Empowering Design Innovation for Healthcare Wearables
G
etting reliable sensor data is complex. For
example, an optical heart-rate sensor is
actually sensing the changes in an electric
current. Heartbeats cause the volume of arterial
blood to change synchronously with each pulse.
The change in volume changes the amount of light
absorbed and reflected as it travels through live
tissue. When that light exits the tissue and enters
a photodetector, it changes the output current. By
creating a sensing system that carefully sets up a
proper series of dominos, a current sensor becomes
a heart-rate sensor.
GETTING TO RELIABLE SENSOR DATA:
Interaction Between Electronics,
Optics, and Mechanical Design
IAN CHEN, Executive Director, Industrial & Healthcare Business Unit, Maxim Integrated
This article will illustrate sensor
data reliability challenges using
an optical heart-rate sensor
as an example. However, the
complex nature of sensor
quality applies to most sensors,
not just optical ones.
