Spectral Fingerprinting on a Standard Mobile Phone

Abstract

Spectral fingerprinting of chemical indicators, using computer screens as light sources and web cameras as imaging detectors, is an emerging approach for chemical sensing with the potential to coexist in common consumer electronic devices. The migration of this technique to mobile phones is key to extend this sensing approach to the most ubiquitous and familiar type of instrumentation. Here, we investigate the feasibility and performance of spectral fingerprinting on reference samples using a standard mobile phone as a complete measuring platform, where the screen provides controlled illumination while the front camera is the imaging detector. Key elements for the execution of such experiments are the software design, the definition of the sample layout, the type of alignment between the phone and the sample, and the influence of ambient illumination. This paper demonstrates the feasibility of reflectance fingerprinting on standard mobile phones and identify the operating conditions of the key parameters that produce an adequate evaluation performance.