High blood pressure is an underlying trigger for many of the world's deadliest medical conditions, and the new device, which could cost as little as 10 cents, could help make regular checks more easy, affordable, and accessible.

A key advantage is it avoids the problems of blood pressure cuffs. Using one that is too large or small, or using one incorrectly, can give inaccurate readings and thus a false sense of security, or of alarm.

A paper describing the invention was recently published in Scientific Reports, and the next steps would include making the technology more user-friendly, especially for older adults, testing its accuracy across different skin tones, and creating a more universal design.