slow light to speed up Internet 'Slow' light to speed up the net,
BBC NEWS | Technology | 'Slow' light to speed up the net This article is about slowing down light so the Internet can be speeded up. I did not understant it.
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Figure 3-10A. - Waveguide lens, HORN RADIATORS,
Horn radiators I looked at this hoping to understnad better. I found the “WAVEGUIDE-TYPE LENS†interesting. I could see that it would only work right if the “spiracle wavefront†was shaped right. I suppose the lens would be ground to fit the wavefront.
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Prism (optics),
Link Removed due to 404 Error)
I looked at this hoping to see how to make some light slow down more than other light. It looks here like you have to stand back from the prism to allow the rays to spread out, so you can “cath†them in their various “channels†spread out.
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Image:Light dispersion conceptual waves.gif,
Image:Light dispersion conceptual waves.gif - Wikipedia, the free encyclopedia Here the animation shows that the purple light travels a bit further than the red light. You have to look close, but you can see that the red light overtakes (outruns) the purple light. Then as they continue beyond the prism they are spread further and further.
Image:Light dispersion conceptual.gif,
Image:Light dispersion conceptual.gif - Wikimedia Commons -----------------------------------------------------------
Here you can see a white ball of white light (purple, blue, green, yellow, orange, red) strike the prism. Immediately the colors are separated, with the red shooting out ahead of the pack. The different photons travel over 2/3s of the way across the prism before you can really see that they begin to match up the same way they were originally sent. They strike to back surface of the prism at almost the same time.
Now at this point, I suppose we need a waveguide lense to catch the “spiracle wavefront†and convert it into a “plane wavefront.â€Â
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All this could put a new twist on "modal dispersion." Ordinarily, if there is too much overlap, the signal could be unreadable. The animation above clearly depicts that an overlap of several wavelengths can be reversed.
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BACKGROUND AND SUMMARY OF THE INVENTION,
Link Removed due to 404 Error The use of multimode fiber implies a limited data rate due to modal dispersion. I have tried to find an article that links encryption to modal dispersion, but I have not found one. But, it seems like this could be done. The extent of modal dispersion could be enhanced on purpose to confuse any eavesdropper.
Instead of having a limited cable length of one kilometer, you could have it a hundred miles long, as long as the signal was strong enough.
I see other articles that discuss “modal dispersion†and “encryption†together, but I do not see encrypton based on modal dispersion.
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