Mobile snapshot hyperspectral imaging device for skin evaluation using diffractive optical elements.

Abstract

ObjectiveA mobile handheld snapshot hyperspectral imaging device was developed and tested for in vivo skin evaluation using a new spectral imaging technology.MethodsThe device is equipped with four different LED light sources (VIS, 810 nm, 850 nm, and 940 nm) for illumination. Based on a diffractive optical element (DOE) combined with a CMOS sensor chip, a snapshot hyperspectral imager is achieved for the application on human skin. The diffractive optical element (DOE) consists of a two‐dimensional array of identically repeated diffractive microstructures. One hyperspectral image for all wavelength regions is taken within a few seconds. Complex recalculation of the VIS spectral distribution and image information from the received DOE image requires several minutes, depending on computing performance. A risk assessment on the irradiation sources shows no risk of harm due to the LED radiation.ResultsSkin tone color patches experiments reproducibly deliver images and spectra of different skin tones. First in vivo use of the device identified pigmentation changes within the field of view.ConclusionWe present a working mobile snapshot hyperspectral imaging tool based on diffractive optical elements. This device or future developments thereof can be used for broad skin evaluation in vivo.