Using a shoebox spectrograph to investigate the differences between reflection and emission

Abstract

For various reasons, optics laboratories often become activities of following instructions and being told to look at one thing or another. This approach can prevent students from exploring optics on their own and diminishes opportunities for “play” and discovery, which are critical to learning. On the other hand, letting students simply explore with equipment that they are just learning to use can be risky and expensive. This is particularly true for spectroscopy with monochromators and spectrographs. To help students gain a better understanding of spectroscopy through inquiry-based discovery learning, we have designed a low-budget and durable spectrograph, which we call a “shoebox spectrograph” that students assemble themselves. Our spectrograph (less than $30 per unit, which includes a webcam to collect spectral images) can then be used in discovery-themed experiments enabling students to explore spectroscopic properties of light as it extends to vision without much fear of student destruction. In this report, we discuss how our spectrograph works, its construction, and explore a student experiment that explores reflected light versus fluorescence.