This article discusses the development story behind the wristwatch-type pulse monitor that contains Epson’s sensing technology, and Epson’s plans to grow its healthcare business.
Conventional pulse monitors – including those previously manufactured on an OEM basis by Epson – involve a band wrapped around the finger, which contains a lot of blood vessels. However, finger bands are easily noticed and make it difficult for patients to perform manual work. Epson developed its new product to answer patients’ demands for a pulse monitor that did not require a finger band.
To create this product, Epson drew on its 20 years of experience in pulse sensing technology with the aim of creating a wristwatch-type device. The product that emerged takes advantage of the light-absorbing property of hemoglobin. The monitor directs harmless LED light inside the skin, and then uses light-absorbing elements to measure the amount of light that is not absorbed by the hemoglobin and which is reflected back from inside the body. The amount of hemoglobin in the blood increases when the blood vessels expand – for example after exercise - meaning that the amount of light absorbed by the body also increases. On the other hand, when blood vessels contract the amount of hemoglobin decreases along with the amount of light absorbed. Epson’s product measures the pulse rate according to the amount of light entering the light-absorbing elements.