Step 7: Diffuser

For very point-like light sources, such as the sun, you will find it difficult to form a good, wide, spectrum. In these cases cut a small square of material from a thin translucent bag and fix it over the front of the slit. This will spread the light so you can see the entire slit imaged as a spectrum.
Diffraction gratings &/ made from CDs are more reliable.
Made one, got it working fine, even though my DVD case wasn't quite the right size for the templates. Used pieces of a floppy disk shutter to make the slit. The Instructable could use a photo or diagram showing proper eye position and viewing angle. It's a bit counter-intuitive to be looking mostly "down", instead of along the line of view toward the light source (the hole being large enough to permit quite a range of eye positions...)
A good source for a diffuser is the window from the next bill you get in the mail. You typically don't have to worry about wrinkles, and it's a nice even diffusing material.
Excellent Instructable! I placed my blades about 0.1mm apart. When I looked at the suns spectra, I immediately noticed a multitude of black lines and thought this was a fault in my spectroscope. Thank you for the mention of the Fraunhofer lines. I speculated the lines I saw might be absorption lines but thought that was far too much to expect from such a simple device. When looking at a fluorescent bulb, The two bright sodium lines are distinctly resolved. Your concise and educational instructions led me to relevant web resources and I must say.. WOW!!
And I thought the instuctable on converting a stuffed beaver into a PC case was cool.. This is though is way cooler.. Have you considered rigging a webcam etc into it?
Great!, Really great! Thanks' for the idea.
your dvds look like video cases in that photo
omg i can now have a good reason to own snakes on a plane yay!
Finally, a good use for "Titanic"... lol But seriously, could you also use dvdr's or does it have to be an actual pressed dvd?
Great instructable! Thanks!<br/>Yessss for Eternal Sunshine of the Spotless Mind!!!11 I think I've watched that at least 6 or 7 times =]<br/>Donnie Darko is pretty awesome, too. I should watch that again. <br/>
Great idea... i might have to build me one of those simply for the geek value of saying &quot;I have a spectrometer... do you?&quot;<br/> saying that - &quot;You can then close the case upproudly display it amongst all the other DVDs - the ones you aren't ashamed of.&quot; *cough* Pirates of the Carribean *cough*<br/>hehe<br/>
I have a wide and varied collection of naff movies... Anyway, POTC can't have be that bad given the business done on POTC2 and that will be done on POTC3.
Teenage Girls + Johnny Depp and Orlando Bloom = $$$$$$<br/>Period.<br/>
POTC2 = booty (heheh) in every sense of the word . . . <br/>
Thumbs up! This is so cool! I went all around my house looking at all my different lights. lol. Great instructable!
Neato! Thanks for posting. I've seen other DIY spectrometers, but yours is actually spiffy looking. Half a cheer for this! Hip-hip Hoo!
<a rel="nofollow" href="http://sci-toys.com/scitoys/scitoys/light/cd_spectroscope/spectroscope.html">This . . .</a><br/>
Yep, as I said in the acknowledgement there are others around. I did it this way to make an integrated solution, DVD and DVD case, both used for the majority of the unit.<br/><br/>PS Than... = Thanks (from the half cheer...)<br/>
OH! Right. I thought . . . heheh :)
Some dvd cases have the discs held in, differently can this be an issue? or is it all good
I focused on the typical Amaray black DVD case, much copied by virtually every other supplier. Obviously the transparent cases won't be much use, and if the disk is not held in the same position or the case is one of those cardboard ones, that won't work either. However I'll guess that 50% of disks are in these standard cases. The important factors are: position of the disk, a deep rim to hold the wedge parts in place, black or at least opaque case to shut out the light, and standard thickness to fit the template.
Could this work on the thinner DVD cases, also?
Probably... The reason I chose the normal thick case was because the edges are deep enough to hold the wedge parts firmly in place. Therefore the DVD insert template is setup for this size of case. A thinner case would need a thinner template, and probably a different fixing mechanism.

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