I understand how magnetic waves are produced: the oscillation of electrons, whose frequency allows the penetration of all light, except that of the colour which we see it as. E.g. we see a green apple, as it absorbs all the colour shone on it, but reflects the green.
My question: if radio waves penetrate through objects, why aren’t there loads of devices which allow us to see other objects through other objects E.g. X-Ray specs
Well, you try and fit an X-ray device into a pair of glasses. And make it non-nads-damaging.
The trick is getting the right frequency of waves that will pass through your secretary’s dress but reflect what mysteries lie beneath, ya perv 
Remember that the more energetic a wave is, the greater likelihood it’ll do cellular damage. There is already enough controversy over the effect of RF in close proximity to humans (cell phones) and lower frequence EMI from high tension wires.
The most basic answer I can some up with is that at standard radio frequencies, objects are resonant (they absorb energy) not reflective. Even x-rays don’t reflect off the bones in our body- the film is placed behind the subject and the subject’s bones block some of the rays from reaching the film, where we see the lighter image of a bone.
My main point is not really with the X-Rays, but more with the ability to detect light waves which have penetrated objects, which we don’t seem to currently have. Surely as light waves are just higher frequency radio waves, which consequently do pass through objects, we should be able to see/detect the light waves??
Yeah, we do have that technology; they’re called your eyes.
Or a camera.
Maybe I’m just missing your question here, but we do see light waves that pass through objects–that’s why we call some objects transparent.
Well, the above, and the fact that the radio waves that pass through the secretary’s dress and body (this is environmenal RF, I’m talking about here) and reach your eyeballs will largely pass through your eyeballa, too. And those that don’t will be at wavelengths that your rods and cones don’t respond to. If you want to see just through one layer of cloth and titillate yourself with what’s behind the cloth, you have to find the radiation of an energy and wavelength that will pass through the cloth and bounce back off the body, pass through the cloth again, pass through your cornea, get focussed by your lens, and activate the rods and cones of your retina. Once you have found the specific section of the EM spectrum that can do this, you have to find a way to fire the energy at your target.
Ok…
Without being pedantic, opaque objects. radio waves pass through opaque objects but lightwaves do not (energy-wise for energy-wise)
If you aim light at any object, what the light does depends on the wavelength of the light. Optical light bounces off of a human being, for example. X-rays pass right through–except that they are reflected by bones, so if you put x-ray film behind the person you’ll see the bones. What radio waves do depends on the frequency of the waves. At the wavelength of your typical radio station, mostly they’ll just pass on through the person–and there’s you’re problem.
They just go through, unaffected. They aren’t reflected by bones, or absorbed by underwear. If you put a radio detector behind the person, you wouldn’t see anything special if the waves aren’t changed by the person they pass through. Even if the radio waves are changed, the changes are going to be pretty smeary because radio waves have long wavelength. If the wavelength is ten centimeters, for example, you’re not going to get a clear picture of any object that’s not significantly bigger than ten centimeters, so the distortion of the waves might reveal the gross shape of the person, but it won’t tell any details. If the wavelength is 5 meters, you’d hardly detect the person at all.
That’s why x-rays work so great–they’re very short wavelength, yielding a sharp image, and they are strongly affected by some things (bone, metal, etc.) and not affected much at all by others (flesh, the sides of suitcases, etc.)
Bolding mine.
Well the first entry in my “American Heritage Dictionary Second College Edition” says Opaque is “Impervious to the passage of light”, but the second entry says “Imprnetrable by a form of radient energy other than visible light”.
So opaque can mean that radio waves will not pass through. For example a Faraday cage may be made from screening that passes light, but not radio waves (at the design frequency).
That’s INPENETRABLE!
Why don’t we have a spell check?
For a clear image, both the object you’re looking at and your detection device must be considerably larger than the wavelength you’re using. In general, waves of any sort (electromagnetic or otherwise) will pretty much ignore obstacles smaller than the wavelength. There’s many objects which are opaque to radio waves, but we don’t realize it for this reason: The radio waves go around the object, rather than through it.
For the record, by the way, rayon is completely transparent to certain frequencies of infrared. Use this information only for good.
That’s right. Didn’t Sony recall/modify some of their early model camcorders with the infrared illuminators because of that issue?