The Hand Spectroscope
The cheapest spectroscope in the world!
With this easy to build spectroscope you can examine the spectrum of any light source: glowing bodies (sun, incandescent light bulb), fluorescent lamps, etc. On the nano-meter scale you can read the wave length to 5 nm accuracy.
This kit is not pre-punched, the parts need cutting out with scissors or a craft-knife
Complete with diffraction grating and magnification lens.