Teeny-Tiny Spectrometer Sensor Could Supercharge Smartphones to Drive Citizen Science

Scientists from Aalto University, Shanghai Jiao Tong University, Zhejiang University, Sichuan University, Oregon State University, Yonsei University, and the University of Cambridge have unveiled a "lab on a chip" that, they say, could lead to everything from better smartphone cameras to improved environmental monitoring.

"We've demonstrated a way of building spectrometers that are far more miniature than what is typically used today," explains Ethan Minot, professor of physics at OSU's College of Science, of the work led by Finland's Aalto University. "Spectrometers measure the strength of light at different wavelengths and are super useful in lots of industries and all fields of science for identifying samples and characterizing materials."

Existing spectrometers are in common usage, but are too bulky to make easily portable — and far too large and expensive to integrate into something like a smartphone. What the team has created, though, is considerably smaller — capable of taking the very smallest of today's spectrometer technology, roughly the size of a grape, and putting it on the tip of a human hair.

“Our spectrometer does not require assembling separate optical and mechanical components or array designs to disperse and filter light," explains project co-lead Hoon Hahn Yoon of the secret behind the sensor's size. "Moreover, it can achieve a high resolution comparable to benchtop systems but in a much smaller package."

The resulting sensor can be controlled electrically to absorb particular colors of light, which the team claims gives it scalability and usability its rivals lack. "Integrating it directly into portable devices such as smartphones and drones could advance our daily lives," Yoon claims. "Imagine that the next generation of our smartphone cameras could be hyperspectral cameras."

The team has suggested a range of possible use-cases for the technology, from examining human tissue for medical diagnoses, monitoring environmental pollution in the air, water, and ground, and even bringing previously-expensive analysis technologies to hobbyists in fields including astronomy and geology — measuring the light spectra of a star to identify it, for example, or identifying gemstones by their light absorption.

The team's work has been published in the journal Science under open-access terms; at the time of writing, no roadmap to commercial availability had been disclosed.