Researchers have developed a wireless handheld spectrometer that is compatible with smartphones to provide users with spectral images of patients in real-time. Researchers examined how it can be used as a point-of-care medical diagnosis tool in Biomedical Optics Express.

The device, which can measure oxygen saturation in a person’s blood, can identify wavelengths from 400 to 676 nanometers at 186 areas simultaneously. Additionally, the spectrometer uses a complementary metal-oxide-semiconductor (CMOS) camera to wirelessly transmit images to a smartphone for quick diagnoses by providers.

"The easiest way to use a spectrometer is to wave it over the part of the body or object being examined," said first author Fuhong Cai, with Hainan University in China. "However, many homemade portable spectrometers use a smartphone camera to acquire data and a phone cradle that contains other necessary optics. The cradle can be hard to align correctly and makes it awkward to wave the smartphone over the body."

In the study, researchers used the pencil-like spectrometer to analyze images of a patient’s hand. Images were sent to a smartphone and presented as a 3D image data cube. Results of the 16-second videos of 200 spectral images showed the device was able to distinguish the fingers and palm of the hand while detecting differences in hemoglobin distribution.

"We want to develop ways to use machine learning algorithms to analyze the massive amounts of data that could be collected with the portable spectra imager," said Sailing He, with Zhejiang University in China, a member of the research team. "We also want to create software for smartphones that uses spectral imaging data to measure meat freshness, for example."