Introduction to the theoretical background and applications of a spectrophotometer

This lab report was composed by two students from the Advanced Materials Science study in the context of an introductory lab course on optics. It contains a brief introduction on the physical phenomena needed to describe the functioning method of a spectrophotometer, such as the different ways a photon can interact with materials (transmission, absorption and reflection) as well as the term "extinction" and how it can be calculated from the light intesities before and after interactions with the materials. Furthermore, the experimental setup of a spectrophotometer as well as the Czerny-Turner monochromator is described. Then, the experiments that were conducted (Absorption, transmission and extinction intensities of light shone through a red and blue filter) as well as the concentration of a Methylene blue solution calculated via Lambert-Beer Law, were explained and their results were analyzed. In conclusion, we (the students) were able to conduct the experiments successfully. It has to be noted that this is the version prior to correction by the professor.