On Friday, 26 September, the city of Pisa hosted Bright – the European Researchers’ Night. At the Department of Chemistry and Industrial Chemistry, we welcomed hundreds of high school students, and of course there was also a session dedicated to our research project! The students were able to observe and interact with two instruments from the department’s historical collection: a Hilger spectrometer and a Rowland diffraction grating. Taking these beautiful objects as our point of departure, we guided our audience through the early discoveries of optics, beginning with Newton’s celebrated experiment on the decomposition of white light using an equilateral prism, and relating these milestones to the investigative methods characteristic of modern chemistry. Thanks to the expertise and the teaching apparatus of Professor Domenici, we were able to employ a white light source alongside numerous optical elements – lenses, mirrors, prisms of varying angles, as well as more distinctive devices such as a Fresnel prism. The students also had the opportunity to handle transmission gratings for teaching purposes, together with the Rowland grating from the historical collection. With these instruments, the fundamental concepts of Refraction, Reflection, Scattering, Interference, and Diffraction were introduced, with the students themselves actively manipulating prisms and other optical components. Equipped with this new understanding of light–matter interaction, they could then appreciate the use of a modern portable spectroscope, as well as the historical Hilger spectrometer, passing a beam of white light through the apparatus, selecting individual wavelengths within the visible spectrum, and observing the resulting colours through the slit.
