If the answer is YES, a related follow-up question: if each visible color of the spectrum were to measure a centimeter in width, how far would I have to move the sensor from the red to detect the change from infrared to microwave, then to radio?
In the knowledge that Sir William Herschel discovered infrared by repeating Newton’s experiment, but with a thermometer to measure the temperature of each component of the spectrum, and after placing the thermometer a bit to the side of the red light, in darkness, noticed quite by accident that the device would still register heat, therefore an invisible yet very real component of light was there, warming the thermometer.
A few practical issues:
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https://asgs-glass.org/optical-transmission/ some examples of transmission spectrum for different glasses. So not all wavelengths will pass through.
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Everything above absolute zero radiates photons. The prism, the detector, etc.
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The radiation spectrum is usually drawn using some type of non linear mapping, as the ranges are quite large.
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Depends on the material of the prism. A material being transparent to visible light does not imply it is transparent for other wavelengths, too.
This is true. For example, many plastics are opaque in the UV range. That’s why in UV spectrophotometry you need to use special cuvettes made out of quartz. Opacity and transparency of different materials in different wavelengths tends to be really surprising. You would never guess that a specific wavelength can’t pass through glass, but can pass through something that looks totally opaque to us.
Edit: spelling
special cuvettes made out of quarts
That’s an absolute unit of a cuvette. I think you might have meant “quartz” :)
Good catch! I don’t know how these mistakes sneak in all the time. I should probably read the message three times before posting.
In theory yes, in practice, I think it would depend what your prism is made of. A given material is not transparent to all wavelengths.
My thoughts exactly.
If you want to refract something other than visible light, you may need to switch to some unexpected materials, like some ceramics or plastics. The material has to be transparent in the wavelength you’re interested in, so optical transparency probably doesn’t align with that at all. A special prism like this won’t look as cool as a piece of glass or transparent plastic.
The size can’t be smaller than the wavelength you’re interested in. If you’re ok with a prism the size of a bus, you can use it refract radio waves. If a traditional pocket sized prism is more like your thing, then radio waves are out of the question, but microwaves should still be fine.
There’s an old Sixty Symbols video where they build microwave prisms out of triangular pieces of cardboard filled with loose pellets of wax. Since the pellets are smaller than the wavelength of the microwaves, they behave as though the prism were solid wax.
Official expensive microwave prisms are made from foam that very closely resembles the PEfoam you put under wooden flooring.
If you’re ok with a prism the size of a bus, you can use it refract radio waves.
Well, 300mHz has a 1 meter wavelength, so you refract some portable radio transmissions
If you’re interested in 1 m wavelength, the prism has to be bigger than that. Let’s go with 2 m to be on the safe side, you could probably move a prism like that with a lorry.
This is exactly how infrared was discovered. The were measuring the temps of each of the colors and then moved it off to the side with ‘no light’ and it still got hot.
Green has the largest spectrum among the colors of the visible spectrum with a difference from shortest to longest wavelength at about 85 nm. If this were assigned a length of 1 cm, you would have to slide 2.1 cm down to enter infrared territory. From there, the infrared spectrum would be 11,755 cm wide (117 meters) before you would slide into microwave territory. The microwave range would be about 11,752,941 cm wide (11.7 kilometers) before sliding into radio waves. The radio wave spectrum would be much, much larger
Green has the largest spectrum among the colors of the visible spectrum with a difference from shortest to longest wavelength at about 85 nm. If this were assigned a length of 1 cm, you would have to slide 2.1 cm down to enter infrared territory
I think this is incorrect. The angle subtended by a given portion of the spectrum is not linearly correlated with the wavelength. The angle is close to zero for long wavelengths, and rises sharply for very short wavelengths.
This has nothing to do with the refraction portion of what OP asked, I’m answering the second question by arbitrarily assigning a length of one cm to one color’s range of the visible spectrum and then applying that arbitrary measure to the rest of the spectrum.
The visible spectrum is from 380-750nm, IR alone is 750nm - 1mm (or 1000000nm), so really far I imagine.
If IR starts at 750nm, you don’t have to go very far to see it. 751nm would count as infrared.
Of course it’s not a clear line like that, but you get the idea.
Don’t longer wavelengths bend less when going through a prism? The bands of infrared, microwaves, and radiowaves might be bunched up pretty close to each other.
That’s an excellent point that I’m not sure anyone considered here. I believe in air index of refraction is a function of (1/wavelength)^4. I didn’t remember if that’s broadly the case for other media/materials.
I believe in air index of refraction is a function of (1/wavelength)^4
Isn’t that for Rayleigh scattering, not refraction?
Oof yes!
