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DIFFRACTION GRATING (Experiment Pack)This pack contains 3 different transparent film holographic transmission diffraction gratings. 1000 lines/mm, 500 lines/mm and a crossed axis grating . The high line density produces a wide coloured spectrum of the observed or projected light source similar to a prism. Make a hand spectroscope. Size 15.2 x 3.8cm sufficient for four 35mm slideholders which can easily be made from the cardboard box. Instructions and experiment sheet included. Ref: OPF0002 | Price: £7.99 |
The performance of this ultra-low cost spectroscope is comparable with instruments typically costing £80. 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. [ You are not allowed to view attachments ] 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).Nb. 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.
Telescope, camera, table, etc + CD vs Telescope, camera, table, etc + £9What is the difference in cost as a percentage and what is the difference in performance? The £6 would be well spent, in my opinion. Most Scientists are after the best possible result for as much money as they can afford.
(I know that, in practice, a better spectrometer would be easier than a strong enough magnet)
I'd like to know if anyone has come up with a way to read-out the intensities of the recorded spectral lines. There's lots of programs (e.g., MS Digital Imaging) that let you you first download and then manipulate/adjust "pictures" from these cameras - has anyone figured out a way to get those programs to indicate (with a number) how "bright" any given spot on them is?