Portable optical fiber coupled low cost visible spectrometer

We developed, implemented and tested a portable low cost spectrometer that covers the visible wavelength range between 400-800 nm. The system is intended to be employed mainly for educational purpose. Hence, open source platforms have been extensively used both in software (Python) and Hardware (Arduino). Main elements of the system are the optical coupling unit based on duly collimated multimode fiber, a ruled linear gating as dispersive element, and a RGB three line optical sensor with 5300 elements. Digitalization is realized by a microcontroller platform from the Arduino family. Data is send over serial USB to a Python based application that permits further data processing and visualization. Calibration is done backed on a LED ladder that covers the whole visible range. Good linearity is observed, and also resolution is comparable with commercial spectrometers. However, a moderate signal to noise ratio is observed. (C) 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (htlp://creativecommons.orgilicens es /by-nc-nd/3.0/). Peer-review under responsibility of ISEL Institut Superior de Engenhal a de Lisboa, Lisbon, PORTUGAL.