The development of a single beam spectrometer kit that works with quality smartphones for studying diffraction and the spectrum of light in basic education classrooms

This research aims to design and develop a single-beam spectrometer kit that works with smartphones of good quality for studying diffraction and the spectrum of light, as well as to investigate the learning behavior of 30 students in grade 11, selected through purposive sampling, while engaging in learning activities with the single beam spectrometer kit. A single slit was created by cut on an opaque cardboard and a cut on paint applied to various types of glass slides. Experiments were conducted with a fluorescent light source, and images were captured with   a smartphone. The images were then analyzed using ImageJ software to evaluate the quality of the spectra.             The results showed that the slit made from metallic silver paint provided the best quality, with clarity that allowed light to pass through effectively and smooth edges of the slit. The slit size was approximately 0.1 millimeters, producing images with distinct spectral lines for each wavelength, offering clear resolution. And the overall assessment of students' learning behaviors in terms of teamwork and skills in thinking and conducting scientific experiments is at a good level after using the fabricated spectrometer kit.