Scientists at the University of Cambridge, in collaboration with the startup GlitterinTech, have created a new optical spectrometer chip priced at approximately $10, which offers the accuracy of traditional laboratory equipment in a device small enough for wearable technology. The sensor, measuring only a few centimeters, demonstrated 100% accuracy in identifying various substances, including foods, plastics, and medicines during initial tests. It also showed the capability to monitor health markers such as blood glucose and alcohol levels without requiring invasive procedures.
The development represents a new class of optical spectrometer, designed to overcome the historical trade-offs between size and performance in miniaturized spectral analysis tools. Conventional compact spectrometers often sacrifice measurement range, resolution, or accuracy, limiting their utility to basic identification tasks. This new convolutional spectrometer, however, maintains high precision and strong noise tolerance while operating with minimal computational overhead. It functions by directly applying a mathematical operation known as convolution to incoming light, utilizing a series of optical components with repeating spectral responses. Fast Fourier transforms then process the data to reconstruct the spectrum.
The chip is built on a silicon nitride photonic platform and integrates onboard electronics. It operates across a near-infrared wavelength range of 1200 to 1700 nanometers and can collect and process measurements in under a second. This broad spectral range and rapid processing time are critical for diverse applications, from industrial quality control to real-time health monitoring.
In addition to identifying materials, the sensor accurately quantified concentrations in both aqueous and organic solutions, reportedly outperforming commercial benchtop spectrometers with an accuracy of around 0.01%. For biomedical applications, the device successfully measured skin moisture, blood alcohol, blood lactate, and blood glucose under simulated physiological conditions. Researchers also tracked glucose levels over an extended period in one participant non-invasively. While this demonstrates promising potential for non-invasive glucose monitoring, the researchers emphasize that further testing is necessary before the technology can become a medical product.
Professor Qixiang Cheng, who led the project, stated that the goal is to make spectrometry as widespread as temperature or motion sensing. He noted that the work distinguishes itself by its technical readiness for real-world conditions, not solely its laboratory performance. The sensor also maintained functionality across a wide temperature range, from -20°C to 80°C. This advancement could enable a new generation of compact sensors for continuous health monitoring, food safety checks, and industrial process control.