These glasses (and contact lenses) allow the wearer to see infrared, ultraviolet, and many other electromagnetic bands which we cannot see naturally.

The lenses act as spectroscopes, and photochemically shift the light into our "visible light" spectrum. Of course, separate lenses are required for spectrums below or above ours, and for the extremes (e.g., gamma).

WARNING: It is not recommended to expose your eyes to Spectrolenses for extended periods of time. Do not drive while wearing Spectrolenses. If headaches or nausea ensue, discontinue use of lenses and contact a physician.
-- rgovostes, Oct 15 2004

Rainbow Glasses https://secure.avdn..._by_an_bye_and_bye&
2nd item on the page in this science experiment catalog. [jurist, Oct 15 2004]

How to make your own spectroscope http://www.scitoys....e/spectroscope.html
[jurist, Oct 15 2004]

Frequency Doubling Crystal http://www.rp-photo...uency_doubling.html
It's possible at least to go from IR to green... [cowtamer, Apr 19 2011]

Nonlinear Frequency Conversion http://www.rp-photo...ncy_conversion.html
Apparently tripling, quadrupling, etc. is also possible. Not sure if this works with non-coherent light, though... [cowtamer, Apr 19 2011]

//photochemically shift the light// - how?
-- vigilante, Oct 15 2004


Are "Spectrolenses" similar to the Rainbow Glasses sold in kids' science experiment and joke catalogs? [see Link] These glasses were used in a demonstration on how to build your own Spectroscope.
-- jurist, Oct 15 2004


(+) From me -- this is not necessarily as crazy as it sounds -- some green laser pointers are actually IR lasers with frequency doubling crystals in them. Any photonics experts out there to comment?
-- cowtamer, Apr 19 2011


these colors can only be made visible by replacing or overlapping other colors. You can never have a true full color image including this data.
-- WcW, Apr 19 2011


//this is not necessarily as crazy as it sounds //

One problem would be to maintain the direction of the light. If you had a lens made of a frequency-doubling material, and you shone red light at it, you'd surely just see a blue haze?

Conversely, there are plenty of frequency-reducing materials - that's just fluorescence. Put a fluorescent lens in your eyes and shine UV light on it, and I think you'll just see a diffuse glow.
-- MaxwellBuchanan, Apr 19 2011


[-] for not just this, but several other reasons too...
-- Wrongfellow, Apr 19 2011


MaxwellBuchanan, I'm not sure if a transparent material of frequency doubling material would necessarily destroy the direction of the light, as the coating on a fluorescent tube might. The output from green laser pointers is still straight, after all. If you could have a frequency-doubled copy of the wavefront entering the lens, I don't see why you wouldn't see an image (not saying that you will, of course -- I have yet to lay my hands upon such a crystal).

By the same token, I wonder if we could create "UV Glasses" by doping glass with fluorescent material...but I think in this case you might be right about the blue haze...

Does anyone have a green laser pointer they can take apart and hold up to an IR source??? :)
-- cowtamer, Apr 20 2011



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