Laser wristwatches are nothing new to James Bond fans who have watched 007 use his laser-enabled watch to cut his way out of a few jams. But laser tech is relatively new to health-monitoring wearables in the consumer market. And Laserland looks like where we’re headed with the latest innovation from Rockley Photonics, a company that specializes in silicon photonics chipsets. They’ve unveiled a new super-small micro-transfer-printed (mTP) laser that’s intended for commercial use, looking to replace LED sensors that wearables, including smartwatches, currently use to monitor bio-signals.

The science of light, photonics (right there in the name Rockley Photonics), is used to detect, control, and generate photons and light waves. Fiber networks have long employed photonics to transfer data from point A to point B. By capturing the physical amount of light and its variations on human skin, LED sensors in wearables use photonics to detect and transmit bio-signals including oxygen saturation, blood pressure, pulse rate, and heart rate. But LED sensors have limitations; the broad spectrum of LED light lacks the precision of lasers. The mTP laser’s spectrum width of light is many orders of magnitude narrower — more than 1 million times — than a typical colored LED spectrum width. That translates to a substantial increase in sensitivity by replacing LED sensors with laser ones.

In super-small packages that are well-suited for integration with consumer-grade wearables, Rockley’s integrated chip — which creates a laser — is about the size of a pencil point. They’re calling it “the world’s highest-density broad-wavelength laser spectrophotometer chip,” intended for use in a range of wearables and smart clothing, as well as VR headsets. The component boasts a thin, small footprint in devices and a low manufacturing cost. Aaron Zilkie, Chief Technology Officer of Photonics at Rockley, says, “This mTP laser technology provides a roadmap for the Rockley wearable and related health technologies to shrink in size, by both shrinking the chip size, and simplifying the packaging, thus reducing overall wearable or health-tech device size.”

Rockley is looking to hit the market with this mTP laser technology in early 2024. Its CEO, Dr. Andrew Rickman, says, “Applying the micro-transfer printing process to the production of integrated lasers is a huge breakthrough that we believe will have a tremendous impact on wearable biosensing and on the photonics industry as a whole… By creating biosensing chips that are smaller, lower-cost, and more efficient, we can continually improve our wearable biosensing products.” Zilkie adds, “[mTP laser technology] can also make the lasers more power efficient, therefore reducing the amount of battery power consumed for each laser measurement.” A fictional gadget for James Bond in 1995’s GoldenEye, laser watches seem poised for reality with today’s wearables.