The performance of this ultra-low cost spectroscope is comparable with instruments typically costing much more.
It uses a CD or DVD as a reflective diffraction grating and clearly shows Fraunhofer lines in the spectrum arising from natural light – and distinctive emission bands from artificial sources such as sodium lamps.
Differences between fluorescent lighting tubes – e.g., white light or ‘warm’ light types – can be easily identified by their distinctive emission bands.
The spectroscope is made from virtually indestructible polypropylene and supplied in flat pack form – taking about 30 seconds to assemble. It comes with a free CD but can be used with any CD (or a DVD for higher resolution).
The really intriguing aspect of this device is the use of a common place CD or DVD replacing either an expensive prism or specially made diffraction grating