Spectral images, which contain more color information than is obtainable with a typical camera, reveal characteristics of tissue and other biological samples that can't be seen by the naked eye. A new smartphone-compatible device that is held like a pencil could make it practical to acquire spectral images of everyday objects and may eventually be used for point-of-care medical diagnosis in remote locations.
Potential applications of the new device include detecting oxygen saturation in a person's blood, determining the freshness of meat in the grocery store and identifying fruit that is the perfect ripeness. The spectrometer could also make it easier to acquire spectral data in the field for scientific studies.
In The Optical Society (OSA) journal Biomedical Optics Express, the researchers describe how to make the new pencil-like spectrometer and demonstrate its ability to acquire spectral images of bananas, pork and a person's hand. The new device can detect wavelengths from 400 to 676 nanometers at 186 spots simultaneously.