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/sci/ - Science & Math

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3264895 No.3264895 [Reply] [Original]

Can an antenna be made to give off visible lightby merely raising its frequency?

>> No.3264904

Yes.

Ever seen a radiator glow?

>> No.3264927

>>3264904
A radiator isn't an antenna.
And applying heat doesn't count.

>> No.3264936

>>3264895
Most antennas are sized according to the wavelengths they give off.
It should go with saying that a reliable visible wavelength antenna would be reeeeeeaaaallllyyy tiny.

>> No.3264967
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3264967

>>3264927

>> No.3264976

>>3264927
>doesn't know what heat is

>> No.3264985
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3264985

>>3264927

>> No.3264987

>>3264927
>have you ever derped so hard

>> No.3265070

>>3264936
Right. I looked into the idea in the past. Besides the microscopic size of the antenna, an oscillator to oscillate that quickly is just not electronically possible.

>> No.3265075
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3265075

>>3264987
>>3264985
>>3264976
>>3264967

>> No.3265081

>>3265075
>>3264927

Samefag.

But really, you derped way too fucking hard for it to be a herp.

>> No.3265093

I dont feel like doing the math right now, but damn, the frequency needed to produce nanometer waves would be insane..

>> No.3265096
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3265096

>that feel when you post only once in a thread and someone calls you samefag

>> No.3265105

>>3265081
nope

>> No.3265108

If those weren't samefags, then it's getting way too summer in here.

>> No.3265110

>>3265096
>>3265105

/sci/ doesn't move THAT fast, kiddo. obvious samefag is obvious..

>> No.3265126

>>3265093
here, I googled it.. for red light (wavelength 700nm), the approximate frequency is 4.286 x 10^5 GHz

>> No.3265144

>>3265126
I experimented at one point with the idea of a single piece of metal shaped in such a way that it was both an inductor and capacitor (and would act as an "antenna") forming a self-oscillating circuit. But normal circuit software couldn't simulate it.

>> No.3265169

>>3265126
or 428.6 THz :3

>> No.3265198
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3265198

Yeah, it's simple. Fry it with electricty.

>> No.3265214

Antennae oscillate and give off electromagnetic radiation when electricity is run through them.

The heating element on a stove gives off electromagnetic radiation when electricity is run through it.

A lightbulb gives off electromagnetic radiation when electricity is run through it.

>> No.3265235

>>3265070
kinda this
It's all done with semiconductors mostly and you all know some of them: LED, TFT, CCD... What do you think those are if not antennas? Of course light can't propagate through walls so the range is low unless you use optic fibers.

>> No.3265234
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3265234

Lets get some semiconductors up in this shizz

>> No.3265248

>>3265214
>>3265198
You faggots are retarded. That's black body radiation, not EM from a signal.

>> No.3265258

>>3265248

You're retarded. There's no such thing as blackbody radiation. It's thermal radiation.

>> No.3265264

>>3265235
>>It's all done with semiconductors mostly and you all know some of them: LED, TFT, CCD... What do you think those are if not antennas? Of course light can't propagate through walls so the range is low unless you use optic fibers.
They give off light using a different process than an antenna.

Antennaes use the electric or magnetic field produced by oscillating current flowing through a conductor.

Those devices you listed, don't. They produce electromagnetic energy via discrete electron events. If you get down to it you can think of the individual electrons as the antennae. But in this they are not manmade and so we cannot be said to have "built" them.

The division between radio and infrared is in part defined by what radiation can be produced/received by antennae and what must be produced/received using either heat/temperature or semiconductors (LED's, CCD's Etc). Of course there is some fuzziness. That is there are some far infrared frequencies that can be produced by high-tech antennae.

>> No.3265265

>>3265248
It's time to stop posting.jpg

>> No.3265270

>>3265258
Semantics, whatever, not the point of my post, troll, etc.
>>3265265
No, you.

Seriously, is it possible?

>> No.3265274

>>3265258
Hi there.. in industry, 'blacbody radiation' is a term used to describe radiation from anything approximating a perfect black body. Generally stuff with emissivity > 0.9 is fine. Really depends on the application though.

>> No.3265277

>>3265264

>The division between radio and infrared

Is microwave.

>> No.3265284

Different transmitters and transuders work with different materials and configurations over different ranges of the EM spectrum, so raising the frequency itself isn't effective because of design limits. Although pumping up the power can sometimes force it emit even if it's not designed to.

>> No.3265289

>>3265274

It's thermal radiation from a blackbody. He was being a smartass so I was one in return.

>> No.3265292

>>3265270
its theoretically possible, but the bottleneck is designing an oscillator capable of 400 THz frequencies

>> No.3265319

>>3265292

could you exploit harmonics to achieve this without needed that high of a frequency from the actual oscillator

>> No.3265325

>>3265274
>Generally stuff with emissivity > 0.9 is fine.

I always thought blackbody radiation had to do with the spectrum shape.

>> No.3265328

>>3265319
no.

>> No.3265359

>>3265277
Microwave is radio.

I meant division between IR and Microwave but w/e

>> No.3265369

>>3265264
>If you get down to it you can think of the individual electrons as the antennae. But in this they are not manmade and so we cannot be said to have "built" them.
It's as close to an electric circuit that raises the frequency to such levels as it gets. When you "build" an radio antenna you shape an existing piece of metal, I don't see how it is different when the antenna is an atom.

>> No.3268545

for the record, if you're a Ham, you're free to try...you may legally transmit on any frequency higher than 275 GHz..