determining wave lengths

[123splat]

Mr. Cyparagon,
Doesn't the refractive index of the medium come into play somewhere in there?

 

[mendnwngs]

My 1,000L / mm diffraction gratings came in..

Packing slip says 1000 line / mm diffraction grating, but there's 10 polarizing filters in the bag..

Useful, but not for this application, and not what I ordered. Gotta get on the horn with the company tomorrow..

 

[Cyparagon]

Just like the spectrometer you calibrated - good idea rhd. I'll try it this weekend if I get time.

Doesn't the refractive index of the medium come into play somewhere in there?

Yes. The higher the refractive index, the shorter the wavelength and the smaller the diffraction angle. It would be different with oil for example.

 

[LSRFAQ]

I've measured vandate based 532 at 1.2 nm wide. The 3Db or "Half Width" points were about .6 nm apart. If your looking at it by eye, you could not tell when you calibrated your grating.

A common neon lamp from Radio Shack gives you plenty of well known glow discharge lines which are a tiny fraction of a nanometer wide, and for two bucks plus a line cord and some splices to make a packaged neon lamp safe, how could you go wrong?

Steve