Researchers at Arizona State University have demonstrated the world's first white lasers:
The researchers have created a novel nanosheet – a thin layer of semiconductor [...] – with three parallel segments, each supporting laser action in one of three elementary colors. The device is capable of lasing in any visible color, completely tunable from red, green to blue, or any color in between. When the total field is collected, a white color emerges.
[...] The technological advance puts lasers one step closer to being a mainstream light source and potential replacement or alternative to light emitting diodes (LEDs). Lasers are brighter, more energy efficient, and can potentially provide more accurate and vivid colors for displays like computer screens and televisions. Ning's group has already shown that their structures could cover as much as 70 percent more colors than the current display industry standard.
Another important application could be in the future of visible light communication in which the same room lighting systems could be used for both illumination and communication. The technology under development is called Li-Fi for light-based wireless communication, as opposed to the more prevailing Wi-Fi using radio waves. Li-Fi could be more than 10 times faster than current Wi-Fi, and white laser Li-Fi could be 10 to 100 times faster than LED based Li-Fi currently still under development.
A monolithic white laser [abstract]
See also our story last year: Philips Launches "Intelligent LED Lighting" for Retail Stores.
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Lagg writes:
"Philips put out a press release detailing their new retail lighting system, which is designed for the purpose of saving power by tracking subjects in a room, then increasing or decreasing light intensity as needed. Philips also advertises a secondary feature for providing location based sale adverts to the customer directly on their smartphone. This will require the user to install an app to actually receive the sale alerts, but it's unclear exactly how this tracking will be done otherwise.
Any home automation types in the comments have a theory as to how this will work on a technical level? My best guess is that there are infrared LEDs paired with the lighting fixtures themselves that can be picked up by phones with IR sensors in them. Further, what advantages does this sort of system have in terms of lighting efficiency that an electric eye setup wouldn't accomplish just as well?"
(Score: 1, Funny) by Anonymous Coward on Friday July 31 2015, @11:29PM
and the ultimate cat toy
(Score: 0) by Anonymous Coward on Friday July 31 2015, @11:42PM
From your lightbulb spying on you.
Gives a whole new meaning to 'living in the dark', eh?
(Score: 2, Funny) by Anonymous Coward on Friday July 31 2015, @11:59PM
Finally the white man has a laser he can call his own. No longer is he subjecting himself to using lesser, colored lasers. White power!
(Score: 0) by Anonymous Coward on Saturday August 01 2015, @07:10AM
White pauwr!
(Score: 1, Funny) by Anonymous Coward on Saturday August 01 2015, @12:09AM
SJWs everywhere are demanding that researchers stop spending all of their time developing white lasers and focus their efforts on developing more lasers of color.
(Score: 0) by Anonymous Coward on Saturday August 01 2015, @12:17AM
A-holes in BMWs and Lexii, and Benz are going to be blinding the rest of us even worse than with their silly blue-tint HID lamps-- because you know the companies catering to the more money than brains crowd will be jumping on this. I wonder if they will bring back the little windshield wipers for their headlights when these come out.
(Score: 2) by Adamsjas on Saturday August 01 2015, @12:51AM
Aren't lasers generally collumated?
Wouldn't that present a general problem using lasers for general lighting purposes?
It also says "Lasers are brighter, more energy efficient " (presumably than LEDs). How true is that?
(Score: 2) by SlimmPickens on Saturday August 01 2015, @02:24AM
If you shoot them into a reflective dish they spread out like regular light.
(Score: 4, Informative) by RedBear on Saturday August 01 2015, @12:57AM
This will be fine if the power is low enough that these lasers flying all around the room can't instantaneously destroy expensive digital camera sensors [photofocus.com]. Just learned about that phenomenon recently actually. Wasn't much of a big deal with older dSLRs, but with digital video cameras and mirrorless dSLRs it's a problem. Of course the laser systems in the examples were powerful 5W lasers that would also damage eyes if they weren't constantly moving around.
¯\_ʕ◔.◔ʔ_/¯ LOL. I dunno. I'm just a bear.
... Peace out. Got bear stuff to do. 彡ʕ⌐■.■ʔ
(Score: 2) by bob_super on Saturday August 01 2015, @01:00AM
> in which the same room lighting systems could be used for both illumination and communication.
I have one Wi-Fi box for the whole house, and it doesn't require line-of-sight.
Sure, it's slower than Cat-6, but it's fast enough, thanks.
LED light bulbs are expensive enough, I don't want your $200-per-room wet dream.
(Score: 5, Informative) by TrumpetPower! on Saturday August 01 2015, @01:04AM
It's important to note that this is not true white light; it is, instead, a balanced mixture of three monochromatic light sources (of unspecified wavelengths).
There's great potential for some really nifty things related to human vision, especially for displays. But the light it emits is no different from the light you'd get from shining red, green, and blue laser pointers into the same diffuser. You get a lot of light of those exact wavelengths and absolutely no light of any other wavelength -- though, as with any other lighting technology, phosphors could help broaden the spectrum.
There's also a limit to how many colors you can reproduce with only three monochromatic primaries; see this article for details:
http://www.tftcentral.co.uk/articles/pointers_gamut.htm [tftcentral.co.uk]
The "sweet spot" would be 630nm, 527nm, and 467nm. Be interesting to know what the actual wavelengths of the lasers in question are....
Cheers,
b&
All but God can prove this sentence true.
(Score: 2) by TheLink on Saturday August 01 2015, @01:57AM
https://en.m.wikipedia.org/wiki/Color_rendering_index [wikipedia.org]
The thing about lighting is the light doesn't go straight to your eyes but reflects off stuff.So if the light has just three very skinny bands of r g b, something that is orange might appear red or dark red or even black if it only reflects a specific wavelength most of us see as orange.
(Score: 3, Interesting) by TheLink on Saturday August 01 2015, @02:04AM
(Score: 0) by Anonymous Coward on Tuesday August 04 2015, @02:17PM
More to the point, it cannot really generate all visible colours. Contrary to common belief, it is not possible to mix all colours from just three of them; indeed the sRGB colour space covers not even half of the full visible colour space. In particular, the spectral colours (those normally emitted by lasers) cannot be generated by mixing anything else.
The reason for this is that there are no three frequencies that each only trigger one of the three colour receptor types in our eye.