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"That sounds like a load of utter bullshit."

https://www.photonics.com/Arti...
https://www.eenewseurope.com/n...
https://www.ledsmagazine.com/a...

I guess your "confirmation bias" switch is set to the on position?

That or you did not even bother to check or just assumed that none existed, which is typical of an ignorant person.

If facts will not change your mind how do you expect to become informed? the LED component itself is not the only thing that can fail.

I have personally had 25% of my LED lights fail far too soon, from 4 different mfg's in 3 locations, but my information is purely anecdotal, just like yours is.

Infinite-capacity wireless vortex beams carry 2.5 terabits per second

American and Israeli researchers have used twisted vortex beams to transmit data at 2.5 terabits per second. As far as we can discern, this is the fastest wireless network ever created — by some margin. This technique is likely to be used in the next few years to vastly increase the throughput of both wireless and fiber-optic networks.

These twisted signals use orbital angular momentum (OAM) to cram much more data into a single stream. In current state-of-the-art transmission protocols (WiFi, LTE, COFDM), we only modulate the spin angular momentum (SAM) of radio waves, not the OAM. If you picture the Earth, SAM is our planet spinning on its axis, while OAM is our movement around the Sun. Basically, the breakthrough here is that researchers have created a wireless network protocol that uses both OAM and SAM.

New Optical Fiber Puts a Twist on Data Transmission
“For several decades since optical fibers were deployed, the conventional assumption has been that OAM-carrying beams are inherently unstable in fibers,” said BU engineering professor Siddharth Ramachandran, who designed the new fiber. “Our discovery of design classes in which they are stable has profound implications for a variety of scientific and technological fields that have exploited the unique properties of OAM-carrying light, including the use of such beams for enhancing data capacity in fibers.”

The strategy by Ramachandran, Willner and colleagues, OAM mode-division multiplexing, combines both approaches. They packed several colors into each mode and used multiple modes. Unlike in conventional fibers, OAM modes in these specially designed fibers can carry data streams across an optical fiber while remaining separate at the receiving end.

Ramachandran’s OAM fiber had four modes (an optical fiber typically has two), and he and Willner showed that for each OAM mode, they could transmit 400 Gb/s in just a single wavelength of light — or 1.6 Tb/s across 10 wavelengths — over the course of 0.68 miles (1.1 km).

Keyword is seamless. But that too has been done before. Company went bankrupt.

http://www.photonics.com/Article.aspx?AID=6220

Perhaps future laser weapons won't be like today's lasers and act more like a projectile but at the speed of light, given the recent progress in making light behave like a liquid or a crystal.

If this is as good as they say, they wouldn't have any secrets and would spill the beans.

The fundamental research was done a long time ago(with picture of prototypes); I've read articles about it in Electronics and Wireless World several times over the years, so it's hardly a secret. Any potentially patentable critical element is going to be kept under wraps, obviously.

I think they have found some weaknesses that restrict the usefulness of this technology.

Or they spent 3 years on R&D fixing those weaknesses, like the article says.

Further information of note from the NYT article:

SiOnyx is already commercializing sensor-based chips as a technology development platform for other companies and for use in next-generation infrared imaging systems.

So we're told:
1- There's a decade of peer-reviewed research behind the technology.
2- They have funding and partners already.
3- They're shipping parts now, not at some unknown time in the future.

Either this is real, or Dr Mazur et al are engaging in an exceptionally elaborate, very public and career-ending series of lies (and it's not as though SiOnyx will be a paying proposition if the tech doesn't work). The part of the operation that does look suspect is their web site (Flash warning), but that doesn't prove anything about the physics involved.

The linked article claims the graphene is impermeable to gases, but didn't say exactly which gases. This article says that even the smallest gases can't get through, not even helium: http://www.photonics.com/content/news/2008/August/8/92805.aspx

I think that you are correct. I know that I read somewhere that the helium will be in the top of the pocket, but apparently, there is more within the gas. That is cool. In particular, the seperation appears to be an ongoing process, via the wyoming plant, which is the world's largest.

You can save on fuel, sure, but isn't there currently a world-wide helium shortage? http://www.photonics.com/content/news/2007/October/19/89406.aspx Helium isn't exactly something we can easily produce ourselves like a biofuel or solar electricity.

Here is another article about the "photonic laser thruster," which says

Bae used a photonic laser and a sophisticated photon beam amplification system to demonstrate that photonic energy could generate amplified thrust between two spacecraft by bouncing photons many thousands of times between them.

From this, it sounds like it can't be used to propel a single stand-alone spacecraft, but it can be used to "push apart" a pair of spacecraft. (Spacecraft A is, in effect, the reaction mass for spacecraft B, and vice versa.)

Am I right about this?

Bae also does Acupuncture research, if that reflects on him in any way. NASA saw him fit enough to give him a grant, however.

I don't know what to make of this guy. He doesn't seem like a quack, but I really don't know enough about the subjects to know if what he's spewing is genius or something else entirely.

Bae founded the institute to develop space technologies and has pursued concepts such as photon, antimatter and fusion propulsion for more than 20 years at SRI International, Brookhaven National Lab and the Air Force Research Lab. He has a PhD in atomic and nuclear physics from UC Berkeley. Several aerospace organizations have expressed interest in collaborating with the institute to further develop and integrate PLT into civilian, military and commercial space systems, Bae said, and he has recently been invited to present his work by NASA, JPL, DARPA and the Air Force Research Laboratory (AFRL).

Elsewhere in the comments people have correctly pointed out that it isn't encryption at all and that it is fundamentally incompatible with any router, switch, bridge or even repeater.

The issue that should have killed this idea ten years ago when Shamir pointed it out is that an attacker who has spliced the fiber can read the polarizer without ever looking at a single one of the transmitted photons.

Send the $#$@! key material by bonded courier in a tamper-evident package if it's that important. If for some reason that's not enough then split (e.g. Blakely-Shamir) the key material into shares, send each separately, and recombine when needed.

Are you guys telling me that such a machine could not be built in the next 5 years?

But a silicon laser? Physically impossible

Diode lasers use silicon, or at least compounds of silicon. Some details here and here.

Pretty cool, though that this is the "the first directly pumped silicon laser."

Another first silicon laser? So who was really first?

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http://oemagazine.com/newscast/2004/102604_newscas t01.html

Los Angeles, CA | 26 October 2004 -- Researchers at UCLA have demonstrated the first silicon laser, which could lead to more effective biochemical detection, secure communications, and defense against heat-seeking missiles.

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http://www.intel.com/technology/silicon/sp/

First Continuous Silicon Laser

In a paper published February 17, 2005 by the prestigious scientific journal Nature, Intel researchers disclosed the development of the first continuous wave all-silicon laser using a physical property called the Raman Effect. They built the experimental device using Intel's existing standard CMOS high-volume manufacturing processes. This is the third silicon photonics paper Intel has published in Nature since 2004, beginning with the modulator breakthrough (see the Learn More section).

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http://www.photonics.com/readart.asp?url=readartic le&artid=325&bhsh=1050&bhsw=1680&bhqs=1

PROVIDENCE, R.I., Nov. 21 -- Silicon has made its way into everything from computers to cameras. But a silicon laser? Physically impossible -- until now. A Brown University research team led by Jimmy Xu has engineered the first directly pumped silicon laser by changing the structure of the silicon crystal through a novel nanoscale technique.

The lab says the weapon, developed by the laboratory's directed energy directorate, employs a two-wavelength laser system and is the first of its kind as a hand-held, single operator system for troop and perimeter defense. The laser light used in the weapon temporarily impairs aggressors by illuminating or, as the lab calls it, "dazzling" individuals, removing their ability to see the laser source

from http://www.photonics.com/XQ/ASP/url.readprod/prodi d.852/QX/readprod.htm

Detectors, on the other hand, are not so easy, at least at the wavelength most people are interested in, 1550 nm.

You mean, this experiment at NEC?

I'm not saying that it's not possible (heck, we knew what happened the last time we thought that), rather that relativity is so entrenched that disproving it would literally change all of physics. It would be an event on a par with the ultraviolet catastrophe that brought down classical physics. As a result, it's not something to be taken lightly.

Considering the pilots in the Cessna got flashed three times, and a helicopter got flashed by the same guy, I'm pretty sure it was intentional.

Still, pre- and post-9/11 stories are interesting to read. Post 9/11 stories abound with "terrorists using lasers to possibly down planes" whereas pre-9/11 stories are about mischief, poor planning, and training pilots not to stare at the beam. Funny how things change.

Pre 9/11 laser-plane stories:
Problems with Laser Light Shows
Outdoor Laser Safety Is in the Hands of the FAA

As another note, we had some asshat firing a pellet gun at car windows back in the 90's. Someone was caught shining a laser pointer at a vehicle and arrested as a suspect. Funny (and scary) thing was listening to the idiot talking heads on TV speculating if a common laser pointer could shatter a car windshield. Yes, they were serious about it.

Post 9/11, they are going all out to hang some asshat out to dry for screwing with planes. The idiots who do this deserve to be punished, but what it really looks like is lasers are getting set up to be regulated and/or removed from public availability.

What's really interesting is that there is an FAA report (April 2001) documenting at least 150 instances of cockpit illuminations between 1996 and 1999. That's about once a week. It wasn't big news then.

I'd love to get one of those 100mW green lasers to mess around with, but now I can't. I would expect some kind of bill being introduced in Congress soon to address this issue now that they are back in session.

"Power" has a unique definition in optics. More specifically it is known as radiant power (aka "radiant flux"), and describes the electromagnetic energy (radiant energy) per unit time. This may be photons per second, or what not. Now "brightness" (aka luminance) is the radiance modified by the eye's response, i.e. what we can see. Finally, "radiance" is radiant power per unit area (like a LCD pixel), per solid angle (some two dimensional angle).

Therefore putting a lens in front of a point source increases the brightness by reducing the solid angle the light is being emitted into.

"Power" has a unique definition in optics. More specifically it is known as radiant power (aka "radiant flux"), and describes the electromagnetic energy (radiant energy) per unit time. This may be photons per second, or what not. Now "brightness" (aka luminance) is the radiance modified by the eye's response, i.e. what we can see. Finally, "radiance" is radiant power per unit area (like a LCD pixel), per solid angle (some two dimensional angle).

Therefore putting a lens in front of a point source increases the brightness by reducing the solid angle the light is being emitted into.

"Power" has a unique definition in optics. More specifically it is known as radiant power (aka "radiant flux"), and describes the electromagnetic energy (radiant energy) per unit time. This may be photons per second, or what not. Now "brightness" (aka luminance) is the radiance modified by the eye's response, i.e. what we can see. Finally, "radiance" is radiant power per unit area (like a LCD pixel), per solid angle (some two dimensional angle).

Therefore putting a lens in front of a point source increases the brightness by reducing the solid angle the light is being emitted into.

"Power" has a unique definition in optics. More specifically it is known as radiant power (aka "radiant flux"), and describes the electromagnetic energy (radiant energy) per unit time. This may be photons per second, or what not. Now "brightness" (aka luminance) is the radiance modified by the eye's response, i.e. what we can see. Finally, "radiance" is radiant power per unit area (like a LCD pixel), per solid angle (some two dimensional angle).

Therefore putting a lens in front of a point source increases the brightness by reducing the solid angle the light is being emitted into.

"Power" has a unique definition in optics. More specifically it is known as radiant power (aka "radiant flux"), and describes the electromagnetic energy (radiant energy) per unit time. This may be photons per second, or what not. Now "brightness" (aka luminance) is the radiance modified by the eye's response, i.e. what we can see. Finally, "radiance" is radiant power per unit area (like a LCD pixel), per solid angle (some two dimensional angle).

Therefore putting a lens in front of a point source increases the brightness by reducing the solid angle the light is being emitted into.

when it comes to images and data -- there are powerful political forces involved

for example -- why can you pay to have satellite images of any place in the world, except Israel? If you've ever wondered why people in the MiddleEast call us Israel's stooge...

But... remember Reagan's "Star Wars" space defense progam? One of the very few useful things we got for all that money was a technology called "adaptive optics." Basically, technology that takes the "twinkle" and the "wobble" out of stars.

Just about everything optical (and maybe even infrared) on Mauna Kea has some AO ability nowadays, using tertiary mirrors that can be adjusted ("tip-tilt") or deformed many times per second by computer-controlled actuators, and/or Orthogonal Transfer CCD's co-developed by University of Hawaii and MIT.

I work a few nights a month on Mauna Kea, and have seen an OTCCD instrument (OPTIC) in use on UH's 88-inch telescope (which also has a simple tip-tilt system available, I think), and it's pretty neat technology. I'm hoping the technology will lead to better image-stabilization technology for photography and videography... and I'd also like to see it "trickle down" to amateur telescopes. :)

Now if you'll please excuse me, I have to get back to my study of high-energy tachyon pulses.

"Primitive" is, well, a subjective term. Most Amish will adopt technology they feel benefits their lives without a foreseeable negative impact on the family or community structure.

For example, Amish Buggy LED Headlights. :)

We can't currently pick up ET signals equivalent to what Earth is broadcasting to space, even if they were coming from Alpha Centauri; they're just too weak.

This is an analog problem of signal to noise ratio, far more than anything else, so faster processing won't help a bit.

A cryogenic Allen array (to minimize thermal noise), especially in space far from Earth, or on the far side of the moon, would help a tremendous amount.

Usually discussions about SETI itself don't bring that up, because of issues of optimism and such, but it was easy to find web hits on the eseentially identical question: can ETs pick up Earth signals?

"No", says this Seti League guest editorial "ET Detection of Earth TV Unlikely" that goes into a little technical detail.

Similar comments by John Dreher, Staff Astronomer, SETI Institute, although he goes on to assume that ETs would be able to pick up weaker signals than humans are able to -- assuming implicitly that ETs will have better analog technology than we do (maybe they do, but that doesn't help us to do the same).

What about ETs actually beaming a signal at us? Maybe they do so to all nearby stars, one by one. Maybe...would we do that?

"...it has been agreed by all relevant groups that we should not be actively sending out messages to try to reach other civilisations", says another page

Ok, so we would not be so foolish as to attract undue attention from an unknown and possibly hostile galaxy, but maybe ETs will be more naive than that. Or a lot more confident (play ominous music here ;-)

So, bottom line, this is a cool topic, but are we planning to build a cryogenic Allen array in space in the next two decades?

I think we should, but any predictions really should be based largely on that one issue.

P.S. the recent lab verification of photons having orbital angular momentum, able to carry arbitrary amounts of information per photon, implies a new medium we'll need to check for ET signals. Maybe that's what all advanced civilizations use.

See e.g. Photons Spin More Data

Here are a few references to increasing solar cell output with Fresnel lenses. Enjoy!

It's interesting that the NIF first full light is now pushed back to 2014. There's a small chance we may just beat them to ignigion.

I work at the Omega Laser(still the most powerfull in the world at 60 Terawatts! ya!) and there is currently construction going on here to complete what is called Omega EP(extended performance) by ~2007. Omega EP will produce an astounding 2.6 PETAWATTS(million billion watts!!) of power for a around a picosecond (so about 2-3 Kilojoules per shot which is much less than the NIF's megajoule scale shots) making it, by far the worlds most powerfull laser when complete. The new laser will use what's called chirped pulse amplification to produce its incredibly high petawatt scale power.

Using the current 60 beam 60 Terawatt (~30Kj) laser to compress a pellet of hydrogen fuel and then just before the moment of maximum inward compression and then stagnation; the EP petawatt beam will fire, producing an instant injection of Mev scale electrons directly into the center of the collapsing target and hopefully producing high fusion yeilds and perhaps even approaching ignition. The Gekko XII laser in Japan with its 500 terawatt scale CPA lser has validated this scheme, which is called "fast ignition", reporting that with the CPA laser used at maximum compression with their 12 beam 40 terrawat laser they've achieve an increase in neutron output(fusion yield) by 1 to 2 orders of magnitude...Can't wait till we can fire ours up!

... is the coolest technology you've never heard of.

For some reason, buried among a zillion dog-eared back issues of "People" and "Sports Illustrated" at the Seattle's Best Coffee shop at the corner of Central and Kirkland Way in Kirkland, Washington, somebody left a copy of Photonics Spectra in the magazine rack. I'm an electronics geek who had never heard of the field, and I probably spent three hours and two quad-damage lattes poring over that magazine. Fucking amazing stuff. Spend some time at the photonics.com website if you don't believe me.

Seriously, photonics looks like it might be the Next Big Thing.

I think your question is fundamentally flawed. You can't ask "What do we use *now* that NASA invented 10 years ago?" Most of the things they are using now won't be in serious commercial use for another twenty years. So most of the things we're using now were invented over 10 years ago.

But, to answer your question anyways, here is an article on Video Image Stabilization and 2D Barcodes. This is another on Superstrong Plastic Films/Strings and Lightweight Composite Actuators.

CCD sensors, create high-quality, low-noise images. CMOS sensors, traditionally, are more susceptible to noise.

Because each pixel on a CMOS sensor has several transistors located next to it, the light sensitivity of a CMOS chip is lower. Many of the photons hitting the chip hit the transistors instead of the photodiode.

CMOS sensors traditionally consume little power. Implementing a sensor in CMOS yields a low-power sensor. CCDs, on the other hand, use a process that consumes lots of power. CCDs consume as much as 100 times more power than an equivalent CMOS sensor.

CMOS chips can be fabricated on just about any standard silicon production line, so they tend to be extremely inexpensive compared to CCD sensors.

CCD sensors have been mass produced for a longer period of time, so they are more mature. They tend to have higher quality pixels, and more of them.

CMOS is generally used in lower quality equipaments.

Canon's SLR's CMOS are that good because their sensor is big. You'd also have an astonishing picture with a same sized CCD sensor.

lemelson, the patent originator, should be well known to the slashdot crowd, but on the internet, institutional memory is an oxymoron

the delay in patent filing is not due to USPTO ineptitude. rather, this is classic lemelson tactics:

1. stake an overly broad patent claim
2. when patent office declines patent on grounds of it being too general, rewrite it, trying to adjust claims such that it takes into account techinical innovations that have occurred since #1
3. repeat steps 1 and 2 until the patent office grants you a patent: congratulations, you've just gotten a patent on someone else's work!

for an example, google for "lemelson" and "machine vision." (here's a link for the google impaired.) briefly, lemelson patented the idea that some sort of machine could do quality inspection of items coming off of an assembly line. he had no invention, he had a wish. he ammended and ammended and ammended that patent for 30 years before it was accepted. in the meantime, laser bar code readers had been invented (by someone else), and he had changed the wording on his patent application to include that technological development. Viola! he invented laser bar code readers, ex post facto, and his estate went on a suing spree.

FWIW, the USPTO changed the policies that allowed this in the mid 90s. still sucks.

A high-efficiency red LED puts out about 2.5 mW of luminous energy in its emission band, and consumes 120 mW of power. That's 3% efficiency. The rest is dissapated as heat. Incidentally, that's why LEDs have a large footprint (the luminous area is very small); so the heat can spread out and the junction characteristics don't change. Incandescents emit light energy outside the visible band, unlike LEDs. This is where most of the power goes, not heat. Thus, incadescent lights achieve about 15 lumens per watt, flourscents get about 50 per watt. Contrary to popular belief, LEDs are in between, the high efficiency models get about 25 lumens per watt.

The most efficient LED right now is %32. You can't buy these yet... they will be used in lights that operate like flourescent lights since they emit UV. This will be the ideal, long-lasting but low power light source.

LEDs are not economical when a flourscent light with electronic ballast can be used in the same situation. In scenarios where the extra electronics required by a flourscent light are too bulky or not enough power is available- this is where LEDs shine. That is why they are the flash-light champs.

It's my understanding that Motorola has already used OLEDs in at least one of it's phones for months now, courtesy of pioneer: http://www.photonics.com/Spectra/Applications/Aug0 1/appsCall.asp

The organic LEDs have kinks to be worked out before they can gain wide acceptance, he said. "Whether it's polymer, large-molecule or small-molecule Fill-factor issues, which involve defects in which the surface area of a pixel is not completely covered with emissive material, can cause problems with display uniformity and crosstalk. Edge growth is a type of fill-factor defect. Single-pixel, and sometimes subpixel, defects are critical factors that determine display quality

03/2001 photonics.com article

Have you been drinking too much coffee? Jeez. Ok, so we're talking about a crystal rather than a gas. I've not idea what kind of impact this has on quantum computing, but thinking about the implications of materials with such a high refractive index is interesting. I remember a while back there was talk about materials with negative refractive indices (Radical Lens Theory Repeals Diffraction Limit), but as far as I can tell it was all theory. Does anyone know (or want to speculate) if similar types of substances could be used to create "flat" lenses?

Some researchers have found it may be possible to produce antimatter using femtosecond lasers. Take a look Here.

Also, for those who didn't understand the linked article too well, there is a nice article on Lycos.

Well, we could remove them with high-power lasers. This has already been proposed, and is quite feasible:

In-depth article on ORION space debris removal project
Photonics Spectra discussion of ORION project
ORION summary
ORION details
Military Discussion of LISK-BROOM
High power laser ablation conference

The plastic in question is pentacene, and it has also been used to make Efficient Plastic Solar Cells. Efficiency is only aroud 2%, a far cry from silicon's 15%, but if they made all the plastic food containers out of it, maybe they could use it as a supplemental supply in California. :-)