Mobile spectrometer

IntroductionHere’s a simple but fully functional DIY smartphone spectrometer, built using nothing more than a CD and a 3D printed enclosure. It’s designed for science education and maker projects. By using the spiral grooves of a CD as a reflective diffraction grating, it splits ordinary white light into a colorful visible spectrum—making wavelength separation easy to observe. The entire body is 3D printed and compatible with most modern smartphones (≤Ø16mm lens). With just a few basic parts and minimal tools, it’s quick to assemble and perfect for classroom demonstrations, science fairs, or home experiments.What You’ll NeedCD (reflective grating) – Use a blank, unused CD for best diffraction claritySlit module (0.1–0.2 mm width) – 3D printed; requires precise XY calibration. Ideally, the slit should fit a single sheet of A4 paper (≈0.104 mm thick)Strongly recommended: calibrate your printer before slicingCalibration modelhttps://makerworld.com/models/1307486Bambu Lab guidehttps://wiki