Imagine being able to analyze the chemical makeup of food, water, or even your skin using just your phone.
Thanks to a breakthrough from researchers at North Carolina State University, that future may not be far off.
A team led by Professor Brendan O’Connor has created an ultra-small spectrometer—a powerful scientific tool for measuring light—that’s small enough to fit on a smartphone chip.
Spectrometers are used in countless fields, from checking air quality and inspecting products in factories to diagnosing diseases in hospitals.
They work by analyzing how light interacts with different materials.
When light passes through or bounces off something, it changes depending on the material’s unique properties. A spectrometer can measure these changes, revealing information about the material’s chemical or physical composition.
The problem is, even the smallest commercial spectrometers are still too big to fit in compact devices like smartphones or wearables.
That’s where this new invention comes in.
The new spectrometer, described in the journal Device, is only a few square millimeters in size—small enough to be built directly into a phone camera sensor.
It uses less than one volt of electricity and can gather data in under a millisecond.
The innovation centers around a tiny component called a photodetector, which senses different wavelengths (or colors) of light.
The team designed a special kind of photodetector made from organic materials—carbon-based compounds that are flexible, lightweight, and easy to manufacture. What makes it unique is its ability to be tuned using small electrical voltages. By applying different voltages, the detector becomes more sensitive to certain wavelengths of light.
Here’s how it works: As light reflects off or passes through a substance, it hits the photodetector. By quickly adjusting the voltage applied to the detector and recording how it responds at each setting, researchers can gather enough data to calculate an accurate “light signature” of the substance. This signature contains the essential information that tells scientists what the substance is made of.
This method doesn’t need any bulky lenses, mirrors, or moving parts—just the small detector and a simple algorithm to process the data.
The result is a device that’s fast, energy-efficient, and able to detect light from across a wide range of the spectrum, from ultraviolet to near-infrared. In lab tests, the prototype performed as accurately as traditional spectrometers and was just as sensitive as commercial photodetectors.
According to O’Connor, this development could bring spectrometry to consumers for the first time. Imagine a phone app that could scan fruit at the store to check its ripeness, test your skin for hydration, or analyze water for safety.
The technology could also transform scientific research, making powerful spectroscopy tools more affordable and accessible in fields like biology, medicine, and materials science.
This tiny spectrometer is just a first step, but it opens the door to a world where analyzing the invisible properties of everyday objects could be as easy as snapping a photo.
