Kyocera unveils miniature optical blood-flow sensor for wearable devices

kyocera sensor

Kyocera has developed one of the smallest known optical blood-flow sensors, which measures the volume of blood flow in subcutaneous tissue. The sensor, only 1mm high, 1.6mm long and 3.2mm wide, is designed for a variety of mHealth applications, including monitoring stress levels or preventing dehydration, heatstroke and altitude sickness by studying trends or changes in blood-flow volume as alerts for these conditions and developing algorithms for detection. It comes in the form of an integrated module, incorporating the laser diode and photodiode into a single ceramic package, based on its established expertise in miniaturization technologies.

Devices equipped with this new sensor will be able to measure blood-flow volume in subcutaneous tissue by placing the device in contact with an ear, finger or forehead. When light is reflected on blood within a blood vessel, the frequency of light varies — called a frequency or Doppler shift — according to the blood-flow velocity. The new sensor utilizes the relative shift in frequency (which increases as blood flow accelerates) and the strength of the reflected light (which grows stronger when reflected off a greater volume of red blood cells) to measure blood-flow volume.

The company envisions a number of cool use cases for its sensor, such as blood-flow sensing earbuds, wearable device for heatstroke prevention and wearable device for mountain climbers. It will offer sensor module samples starting April 2017, and aims to commercialize the technology as a device by March 2018.

Global shipments of healthcare wearables are expected to rise from 2.5 million units in 2016 to 97.6 million units in 2021.