‘Lab on a chip’: Scientists invent new and improved tool to measure light

Scientists and materials researchers have invented a new and improved tool, "lab on a chip," to measure light, according to a press release by Oregon State University (OSU) published on October 20.

An ultra-tiny device

The new tool consists of an ultra-tiny spectrometer that fits on a microchip and is operated using artificial intelligence. It now may lead to upgrades in everything from smartphone cameras to environmental monitoring.

"We've demonstrated a way of building spectrometers that are far more miniature than what is typically used today," said Ethan Minot, a professor of physics at the OSU College of Science.

"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."

The new device could fit on the "end of a human hair," Minot explained, making it far better than traditional spectrometers that require bulky optical and mechanical components.

"Our spectrometer does not require assembling separate optical and mechanical components or array designs to disperse and filter light," said Hoon Hahn Yoon, from Aalto University, who led the study.

"Moreover, it can achieve a high resolution comparable to benchtop systems but in a much smaller package."

When it comes to the colors of light it can absorb, the device is 100 percent electrically controllable, making it scalable and suited for widespread use, the researchers explained.

"Integrating it directly into portable devices such as smartphones and drones could advance our daily lives," Yoon said. "Imagine that the next generation of our smartphone cameras could be hyperspectral cameras."

Opening up possibilities

Those advanced cameras could also allow for infrared imaging and analysis.

"It's exciting that our spectrometer opens up possibilities for all sorts of new everyday gadgets and instruments to do new science as well," Minot said.

Currently, spectrometers are already being tested in medicine for their ability to identify the difference between tumors and healthy tissue, as they can easily pick up on subtle changes in tissue.

For environmental monitoring case uses, spectrometers have the capacity to detect exactly what kind of pollution is in the air, water or ground, and how much of it is there.

"It would be nice to have low-cost, portable spectrometers doing this work for us," Minot said. "And in the educational setting, the hands-on teaching of science concepts would be more effective with inexpensive, compact spectrometers."

But that's not all. The new tool can be used in other wider-ranging science work.

"If you're into astronomy, you might be interested in measuring the spectrum of light that you collect with your telescope and having that information identify a star or planet," he said. "If geology is your hobby, you could identify gemstones by measuring the spectrum of light they absorb."

Minot thinks that as work with two-dimensional semiconductors progresses, "we'll be rapidly discovering new ways to use their novel optical and electronic properties," especially since research into the tools has only been going on for a dozen years.

"It's really exciting," Minot said. "I believe we'll continue to have interesting breakthroughs by studying two-dimensional semiconductors."