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Wireless Internet Access Uses Visible Light, Not Radio Waves
An anonymous reader writes to tell us that a company has demonstrated a new form of wireless communication that uses light instead of radio waves. "Its inventor, St. Cloud resident John Pederson, says visible-light embedded wireless data communication is the next step in the evolution of wireless communications, one that will expand the possibilities in phone and computer use. The connection provides Web access with almost no wiring, better security and with speeds more than eight times faster than cable."
im in ur bawx stealin ur photons
Radio waves are part of the light spectrum?
Looking at the access point can cause severe retinal burns. We are not responsible for retinal damage or permanent blindness as a result of using our product. Thank you, and have a nice day.
WARNING!
Do not look at the internet with your remaining eye.
liqbase
It's called free space optics. The technology has been around a long time, in fact, and for a while it was fairly common on laptops. It was called IrDA, and though it was fairly short range you could use it to transfer files, establish a TCP/IP connection, etc.
I remember playing a Starcraft game with an iMac G3 and PowerBook G3. A friend and I used AppleTalk over IrDA. Unfortunately it was rather awkward since they had to line up, but we figured out you could bounce the infrared beam with mirrors. So we didn't need ethernet, we could play wirelessly...this was in 1998, long before 802.11b became mass-market.
Take off every sig. For great justice.
For how many decades does my university use laser links to our dorms? For how many decades do we have infra red data transmission, e.g. in remote controls?
Last time I checked light doesn't travel through my wall. Radio waves do.
Tinfoil glasses :)
- The Sigless Wonder
This is where you are wrong, sir. And you can test it yourself. Create an HTML document and set the background color past "#FF0000". Crank it up to "#ZZ0000" and your monitor will then begin blasting radio waves at your face.
A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
Uhhhh...radio waves propagate at the speed of light too, being made out of light and all.
However, higher-energy light has a higher frequency. Higher frequency = higher bandwidth. (and, not-so-coincidentally, higher power consumption)
Use Tempest for Eliza and it'll transmit radio at you for real rather than generating a minor html error :P
Can you image how annoying it would be to have light flickering around you all the time from your communicating devices?
You know that thing you looked into when you typed your message. Be it a CRT, LCD or Plasma, it flickers at 40-120 times per second.
Communication applications would flicker even faster to the point you wouldn't notice unless you sent a constant string of 0's or 1's.
Don't get me wrong, I still think it's a bad idea for line of sight and other interference reasons, but flicker is near the bottom of that list.
Well, back to rejecting software patent applications.
It's been investigated but the technology just won't work out. Light sensors have a strong speed/intensity tradeoff. Even with a several-inch wide lens you can't collect enough light to drive a sensor at more than a few kilobits/sec. And people hate to keep pointing the sensor at the opposite party.
And if the room has LED or CCFL lighting the interference from those is mighty intense.
Can you image how annoying it would be to have light flickering around you all the time from your communicating devices?
Oh, cut the bleeding heart crap, will ya? We all have our switches, lights, and knobs to deal with. At this very moment I surrounded by hundreds of thousands of blinking and beeping lights, blinking and beeping and flashing and flashing and I can't take it anymore! They're blinking and beeping and flashing! Why can't anyone stop it? Why doesn't someone pull the plug?!
Oh, say does that Star-Spangled Banner entwine / The myrtle of Venus with Bacchus's vine?
Yes, it seems like they're drawing a couple suspect distinctions in this article. They talk about "light" as being very different from "radio" even though they're both EM radiation, and they talk about "using light" as very different from "using fiber optics", even though it's really just a difference of medium.
I don't really see it working out. We already use that portion of the EM spectrum for... you know... seeing. I guess you could claim that being easily blocked (e.g. by walls) is an advantage, but for most people in most circumstances, being able to pass through lots of materials would be a greater advantage. If you really want tighter security, then instead of relying on walls to block the signal, this technology could be improved by creating some sort of conduit that would go directly from one point to another. Like some kind of fibrous, wiry, cable-like structure between them. I'm sure that would be much better than fiber optics.
1.) There is TCP/IP over Infrared (IrDA) and comes standard on Windows and works also in Linux.
http://web.pdx.edu/~mendyke/ip7780.html
2.) there are many laser link systems out there.
I even worked on one.
http://www.dnull.com/zebraresearch/company-mail.html
3.) The 802.11 standard also includes the 802.11 Infrared (IR) Physical Layer. 802.11 IR defines 1Mbps and 2Mbps operation by bouncing light off ceilings and walls to provide connectivity within a room or small office. This infrared version of the standard has been available since the initial release of the 802.11 standard in 1997.
4.) Spectrix Corporation of Mundelein, Illinois had a proprietary solution for this. I think they are out of business now.
http://books.google.com/books?id=QZrrXcs1R9gC&pg=RA1-PA207&lpg=RA1-PA207&dq=%22Spectrix+Corporation+%22&source=bl&ots=kMxMofcTd7&sig=qd4QvwoREWQloJKwnpmp63j-Z-I&hl=en&sa=X&oi=book_result&resnum=4&ct=result
If you explore the link above from the book "Wireless Computing" By Ira Brodsky Published by John Wiley and Sons, 1997. This book goes in a lot of detail about many IP over optical solutions available at that time.
I am always doing that which I can not do, in order that I may learn how to do it. - Pablo Picasso
The article is utter bullshit.
Using light, as opposed to radio waves is NOT more secure, unless the room has no windows, or others areas for light to escape.
Wiring a room to support it could easily cost $300 (you still need atleast one network drop to the room, and mount the transmitter).
Are there environments where the slight advantages it has may be worth it? sure. but they will be so rare that the cost of the device will stay quite high.
THe article looks like a puff piece designed to lure in investors.
"Because light does not travel through walls, cell phones and government and banking information would be more secure."
It's not a bug, it's a feature, really - it is, please believe me.
1996 called. It wants its HP NetBeamIR Infrared Ethernet Access Point back.
IR access points have been around for years, and they work OK. They can even be made to work through diffuse reflections, so you don't have to have a clear line of sight. But you need a lot of access points to cover a space.