A Spectrophotometer implementation as project-based learning in Photonics Engineering

The construction of a low-cost spectrophotometer as part of project-based teaching for postgraduate students in the field of Photonics Engineering is depicted. The criteria followed in designing this project include considerations about budget, portability and multidisciplinary skills. The proposal has been carried out in the context of a 3 credit Experimental Projects I course, part of the Master in Photonics Engineering taught by the Polytechnic University of Madrid, University Carlos III of Madrid and University of Alcala. During its performance, students have been supplied with all the necessary mechanical and optomechanical hardware, as well as passive and active optical elements and driving circuitry. Their tasks include the manufacture of a diffraction grating by a brand-new nanoimprint technique, the optimization of the optical alignment for improving the optical transfer function and the signal-to-noise ratio at the detection stage, and the programming of the control system and data acquisition in a LabView environment. The outcome is a fully functional spectrophotometer. Although it has been designed and tested with students of photonics, its multidisciplinary and modular character makes it useful also for undergraduate students from different disciplines, such as Industrial, Electronics or Automation Engineering. The open availability of the mechanical and electronic designs further allows its use by secondary teachers as a demonstrator of the different concepts used in their implementation (photonics, mechanics, electronics and software).