Facebook Pitches Laser Beams As The High-Speed Internet Of The Future (pcworld.com)

An anonymous reader quotes a report from PCWorld: Facebook says it has developed a laser detector that could open the airwaves to new high-speed data communications systems that don't require dedicated spectrum or licenses. The component, disclosed on Tuesday in a scientific journal, comes from the company's Connectivity Lab, which is involved in developing technology that can help spread high-speed internet to places it currently doesn't reach. At 126 square centimeters, Facebook's new laser detector is thousands of times larger. It consists of plastic optical fibers that have been "doped" so they absorb blue light. The fibers create a large flat area that serves as the detector. They luminesce, so the blue light is reemitted as green light as it travels down the fibers, which are then bundled together tightly before they meet with a photodiode. It's described in a paper published on Tuesday in the journal Optica. Facebook says there are applications for the technology both indoors and outdoors. Around the home, it could be used to transmit high-definition video to mobile devices. Outdoors, the same technology could be used to establish low-cost communications links of a kilometer or more in length. In tests, the company managed to achieve a speed of 2.1Gbps using the detector, and the company thinks it can go faster. By using materials that work closer to infrared, the speed could be increased. And using yet-to-be developed components that work at wavelengths invisible to the human eye, the speed could be increased even more. If invisible to humans, the power could also be increased without danger of harming someone, further increasing speed and distance.

Comments

Harm

[Rei]

And using yet-to-be developed components that work at wavelengths invisible to the human eye, the speed could be increased even more. If invisible to humans, the power could also be increased without danger of harming someone, further increasing speed and distance.

Yes, because as everybody knows, UV does no damage to the human eye...

Re:Harm

[msauve]

I came to say basically the same, but about sunburn and cancer. Beyond that, the whole article is Bookface marketing puffery.

Re:Harm

[Pharmboy]

385nm is invisible to almost all humans, being on the long-ish wavelength of UV, and I wouldn't really say it was very damaging. Everyone likes to jump on the bandwagon like they actually know something about UV when in fact they don't. I've worked with it over 25 years, still do. Out of the millions of products sold, I've never had an injury reported. People do get hurt with UV, but that is exceedingly rare and usually because they didn't follow directions or did something really stupid.

Inside fiber, it is pretty harmless. Most plastics block it (excepting OP4 acrylic), the vast majority of paints absorb it and won't reflect it. It has a smaller wavelength, thus more waves per centimeter, ie: more data. I'm not saying their plan is good or bad, but blanket calling UV dangerous and not workable is ignorant.

Re:Harm

[Rei]

Indeed, UVA is quite dangerous to human eyes - even though there are other wavelengths that are more dangerous. Metal halide lights for example kick out a great deal of UVA. To prevent eye damage they have to have a filter to block it. In cases where the filter has been damaged it can lead eye damage and even temporary blindness.

I think perhaps the person is confusing the fact that UVA doesn't damage DNA (except indirectly) with it not being damaging to the eye.

Re:Just Because You Can't See It...

[konohitowa]

Why yes. Just like radiation. And viruses.

It's larger!

[konohitowa]

At 126 square centimeters, Facebook's new laser detector is thousands of times larger.

Umm. Than what? Who writes this crap?

You instinctively turn away from visible lasers

[raymorris]

Yeah invisible lasers are normally considered MORE dangerous. When even a 5mw visible laser hits your eye, you instinctively turn away immediately. The extremely bright light is uncomfortable. If you can't see it, you don't instinctively turn away. See Chuang LH, Lai CC, Yang KJ, Chen TL, Ku WC (2001). "A traumatic macular hole secondary to a high-energy Nd:YAG laser".

OSHA and other bodies require EXTRA safety measures for invisible or nearly invisible lasers. (Near infrared fiber optic lasers can appear to be a dim red. They are actually very bright, just on the verge on the wavelength humans can see.)

Re:You instinctively turn away from visible lasers

[Rei]

It seems that that absurdity in pcworld is the author's poor interpretation of this:

If materials were developed that operate in the infrared part of the spectrum, which would be invisible to people, and were even faster than the blue/green light system, the new approach could theoretically allow free-space optical data rates of more than 10 Gbps, Tiecke said.

Re:Just Because You Can't See It...

[rossdee]

Yeah, imagine the bandwidth we could get out of the gamma ray end of the spectrum (which is also invisible to humans)

Weather effects stop transmission of laser light.

[Futurepower(R)]

"Outdoors, the same technology could be used to establish low-cost communications links of a kilometer or more in length."

Weather would prevent transmission through the air outside, of all wavelengths. Raindrops scatter light. Fog scatters light.

Re:Weather effects stop transmission of laser ligh

[locopuyo]

Maybe they could put it in some kind of tubing and bury it.

Here's an idea

[dbIII]

Here's an idea - let's use those laser but safely contain them within glass fibres with the advantage of getting better range and more than line of sight!

You can tell the idea in the summary came from a software company and not a hardware company. Reinventing the wheel as a square thing made of rock.

Stoooooooooopid

[JustAnotherOldGuy]

"If invisible to humans, the power could also be increased without danger of harming someone, further increasing speed and distance."

That's an incredibly stupid thing to say, since it isn't true. Just because it's "invisible" to human eyes doesn't mean that it can't/won't hurt human eyes.

Seriously, the level of stupid in that one sentence makes me dizzy.

Re:Stoooooooooopid ; no, just optimistic

[whit3]

"If invisible to humans, the power could also be increased without danger of harming someone, further increasing speed and distance." That's an incredibly stupid thing to say, since it isn't true. Just because it's "invisible" to human eyes doesn't mean that it can't/won't hurt human eyes.

But this was about UV light spreading out over several square inches at distance. The lens of the eye is cloudy to near-UV light, and won't focus to a spot. The reason it's invisible, makes it less likely to damage your retina.

Tinkering near such sources, you'd want to be careful, of course. Protective gear, for that wavelength, is rather common, because arc welding produces the same light in hazardous intensities.

As a tower-to-tower relay for high speed signals, it's unlikely to impinge on anyone's face. Weather, though, will be a problem. It won't replace microwave links if reliability is important.

Why do we care that Facebook is doing this?

[Transcendent]

Freespace optical communication has been around for a long, long time. It's a problematic system to use in an atmosphere, since anything and everything can degrade the throughput. So, now we get to use a system the is horribly degraded whenever it's foggy, rains, or birds are flying around? No thank you.

Other systems have shown to achieve 10GB/s, so their test of 2GB/s isn't that revolutionary.

Let's stop the clickbait of *random famous company does something that other people have done before*.