Domain: optics.org
Stories and comments across the archive that link to optics.org.
Comments · 42
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Re:LED ... filament?
But that's not what they are talking about here. Those "filament" lamps are nothing but a row of LEDs on a strip.
They're probably talking about this, which has nothing to do with filaments: http://optics.org/news/6/2/6
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What they are probably meaning:
http://optics.org/news/6/2/6
http://www.nature.com/nmat/jou...The writer of the original article should be shot, hung, shot, and then boiled.
It is riddled with so many inaccuracies that it's meaningless.
'10%' - yes - 10% is mentioned ' Our first devices already exhibit an extrinsic quantum efficiency of nearly 10% and the emission can be tuned over a wide range of frequencies by appropriately choosing and combining 2D semiconductors'
But going from that to LED efficiency is ridiculous.It is comedically ridiculous to claim that it's going to result in products this year.
It's worth noting that the best existing 'warm white' LEDs bulbs can already produce about twice as much light per watt as compact florescent.
(if they are made with around double the normal number of LEDs and a more efficient power supply). -
Re:Good.The problem today is that some of these handheld lasers are 10X more powerful than they're rated at.
{Low-cost apparatus designed by National Institute of Standards and Technology (NIST) researchers to quickly and accurately measure the properties of handheld laser devices has shown that nearly 90 percent of green pointers and 44 percent of red pointers tested were out of compliance with federal safety regulations.
Green pointers, which rely on frequency-doubling optics, also emitted “unacceptable” levels of infrared light, reported the team led by NIST Laser Safety Officer Joshua Hadler. It also found one pointer delivering more than ten times the allowable output power in the visible region. Reporting the results of its study on 122 pointers at the International Laser Safety Conference taking place in Orlando, Florida, this week, NIST says that the apparatus has been deliberately designed to be replicated easily by other institutions.
While anecdotal reports of green laser hazards have previously appeared in scientific journals and the media, NIST says its tests are the first reported precision measurements of a large number of handheld laser devices. The tests also showed, unexpectedly, that many red laser pointers are also out of compliance with federal rules as defined by the Code of Federal Regulations (CFR). "Our results raise numerous safety questions regarding laser pointers and their use," the team's paper states.}
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Re:Lumens?
910 lm
http://optics.org/news/2/8/8
"Perhaps because of those tough requirements, only Philips has officially entered the competition thus far – and that was nearly two years ago, back in September 2009. Over the past 18 months, its 910 lm design, which Philips says operates with an efficacy of 93.4 lm/W at a warm-white color temperature of 2727 K and offers a color rendering index of 93, has been put through extensive testing." -
Re:A 21st Century Contact Lens
I think this must be the kind of thing they're contemplating.
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Re:Eh? I thought DNA was DNA...
Or bacteria, which will give you orders of magnitude more DNA overnight than a week of fly collecting, and which are much easier to purify DNA from.
This article also talks about using salmon DNA for lights. They had a good source:
Steckl and colleagues used DNA from Japan. "Salmon fishing is a very large industry in Hokkaido, Japan, some 200 000 tons per year," explained Steckl. "While the meat and eggs are edible, the male roe is normally a waste product but it is very rich in DNA."
That doesn't seem to be the same lab, and that article predates the technology review one. Maybe the Sotzing lab (featured in the technology review article) read the publications by Steckl lab (optics.org article) who used salmon DNA and decided to just use salmon DNA as they did to hurry up and publish rather than spend time seeing if salmon DNA was the only one which would do it.
Of course, it could also have been that the Steckl lab got wind of the Sotzing lab's use of salmon DNA and just beat them to the punch. And these aren't the actual publications from either lab, so it really could be anything, they could have even collaborated. Either way, it seems like they just haven't tested other DNA, the optics.org article quotes Steckl as saying they might try other DNA.
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Re:Use light, not radio wavesLight from non-supernovae stars that are billions of light years away is detectable. Certainly can't resolve individual stars, but the light is readily detectable and isn't blocked by interstellar matter, which was my big point I am trying to make.
You're comparison with the most powerful laser is misleading. The power density of many ordinary lasers exceeds the luminosity per unit surface area of many ordinary non-supernovae stars. You don't need a very powerful laser. Take the Sun, which has an areal luminosity of 60MW/m^2; that's beaten by an ordinary 3kW 200um CO2 beam, which has a power density of 75GW/m^2.
Now, let's move up a gear on both sides. The brightest star ever found has an areal luminosity of only 85TW/m^2 (40*10^6 * (solar luminosity 3.846*10^26)/(surface area 4*PI*(3.75*10^9)^2)). However, the power density of the brightest laser is 200YW/m^2 (YW is Yotta Watts, 2*10^22*10^4W/m^2), which is 12 orders of magnitude brighter than the brightest star, so laser massively beats star again.
Pulse duration makes no real difference to the visibility of the pulse. Small cross-section is ideal for aiming.
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Re:So, time for a REALLY long-baseline telescope?
Two problems with your suggestion. 1) Baseline is not the limit of any planet searches. 2) Planet searches are done with optical frequencies.
You could put a radio telescope on the moon and do VLBI - but not an optical telescope.
The most difficult part right now of detecting planets using Doppler shift is a fixed frequency standard to compare the stars spectrum against - they are measuring centimeter/second movements of the star. Baseline has nothing to do with the current limits. AFAIK, the only optical interferometer of any note is at Keck - and I don't even know if it has been used yet. See this article: http://optics.org/cws/article/research/33693 -
Polariton Lasers Are More Efficient
Here's another good article I found:
http://optics.org/cws/article/research/27439
Again, a more energy-efficient laser sounds like it could be used for nuclear fusion, or even just for more energy efficient consumer electronics (eg. DVD players)
Isn't Laser-TV supposed to be coming out this Xmas? I'd read that Novalux is working on improving the power of their Necsel laser modules for that purpose. If polariton lasers are 10 times more efficient than laser diodes and can operate at room temp, then maybe they'd fill the bill. -
Old news
Electrochromics have been figured out for a long time. You can already buy rear view mirrors for cars and a motorcycle helmet with an electrochromic visor has been around since 2003. Nothing to see here.
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More info on the optics
I found this link on the optical information: red, green & blue lasers.
This is real, and currently the only barrier is that red lasers aren't as stable / powerful / easy to create as blue & green ones.
If Novalux have overcome this, then real TVs using this tech will be on the market in 12-24 months.
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Old news
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Re:Linus Torvalds' Solution
why dont you just encode it all on your fingernails every few months.
http://optics.org/articles/news/11/7/4
just be sure to avoid eating any wendy's chili, identity theft is a problem you need to be wary of, but if you use RAID5 you should be fine.
you may want to also consider mirroring the data to both hands and feet. shoes are important to maintaining data integrity, on toenails. i believe a good manecure and pedicure will increase the write speeds, but that technique is also listed by the NSA as the official method to purge this storage medium, so you should remember to re-write the data afterwards. also be sure to always dispose of nail clippings in different locations, i reccomend subways for guarenteed dispersal and data hiding.
you may encounter some performance hits when using RAID5 during your flight to freedom from NYC, but hopefully you wont be accessing the data much when this situation occurs.
and if you didnt consider keeping all your info on an iPod shuffle with an audio will & testament and comments to loved ones then in the worst case scenario you could atleast have some kickin tunes when the zombies come chasing after you. -
Not new
This isn't groundbreaking. There have been building materials developed before that use fibers to transmit light from outside. I'm a bigger fan of just designing the building so that more natural light finds its way in, rather than resorting to expensive materials and tricks. Windows do an OK job when positioned intelligently. I remember visiting an apartment building in Norwich which had a brilliant design, sunlight made it down columns to each floor and there was plenty natural lighting in the hallways. Amazed me
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intravenous authentication
"Data stored in a fingernail can be used with biometrics, such as fingerprint authentication and intravenous authentication of the finger."
- from the article
What the hell is "intravenous authentication of the finger" -- ?!
Scary!
-kgj -
Re:Are you serious?
For the people who really need the properties of a CRT, flat panel versions are in the works:
http://optics.org/articles/news/11/5/17/1
Literally every pixel has its own electron gun via the wonder of carbon nanotubes.
That said I personally really like the newer LCDs, they have improved drastically in recent times. -
MoronWell, maybe the "poor guy" should have protected his IP-rights better or at least done the same thing as this guy:
"Nakamura was working on a semiconductor called gallium nitride. Some 13 years later he is locked in a bitter patent dispute with Nichia and stands to receive an estimated EURO 17 m if he wins. Why? Because he was first past the post." (the lawsuit which he won)
In short, Jim Russell was just stupid. It's just insanely moronic to spend time and money inventing something revolutionary like optical storage and then neglect your intellectual property rights. If you don't profit from your invention, someone will. When that happens, it's too late to cry.
Just fucking patent everything you invent and only after that decide what you're going to do with it.
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This is very old news
Philips announced they were doing it in March. http://optics.org/articles/news/10/3/8/1 At that time they were doing it too.
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Bell Labs talked about this almost two years ago
Tunable Microlens
No idea if they had patents on it. If this French company got there first, these would seem to be very lucrative patents.
As for SciFi being there first, that's hardly an argument we (Geeks) want to see used. If companies can't make money off a technique or concept because a SciFi writer wrote about it abstractly, they will not invest the money needed to create such a technology. We'd have to sit around and wait for some gigantic government initiative like the Space Shuttle to get technology we've long dreamed for. And even then.. it's rarely in a form we can benefit from.
Remeber, its 1% inspiration/ 99% perspiration.
It's gret these SciFi writers inspired our engineers, but the effort that goes in to producing viable products should not remain un-rewarded.
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Re:Probably an expired patent
Early 1980s invention plus 20 year patent term = patent expiry in early 2000s, therefore Kodak can no longer sit on the technology, and that explains why OLEDs are finally hitting the market.
I believe the problem with mass-production of colour OLEDs was that blue LEDs were developed in the 90's, and they have been the problem in producing colour OLED displays. I don't know about monochrome displays, though. If the technology has been around for so long, it's strange that it hasn't been applied. I just found this page that says Kodak just applied for a patent this year for an improved OLED display method, which means this is probably what will be used if it replaced LCD displays. And that means they can sit on it for another 20 years. Here's a quote...
The OLED display described in patent application WO 2004/053827 uses various sizes of light-emitting elements. The areas of the elements are tailored to suit the eye's response to different wavelengths and also take into account the efficiency of the light-emitting material. The authors say that light-emitting elements made with higher-efficiency materials can be made smaller than elements with lower efficiency materials while producing the same light output. As a result, the blue emitting elements have the largest area, followed by green and then red. The inventors say that this configuration simultaneously increases the lifetime, power efficiency and apparent resolution of an OLED display device.
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Re:"transparent concrete"
I think I saw the article in popular science a few months back. Since I don't have the magazine with me, here is a link to a similar article http://optics.org/articles/news/10/3/10/1
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Re:Fantastic
Like transparent concrete? http://optics.org/articles/news/10/3/10/1
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Translucent concrete
This seems even more practical.
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Old NewsI remeber reading about this in last year's "Coolest Inventions of 2003" located here Further investigation has also found that a guy registered a pantent for the same tech back in 2002 From the article:
The idea hinges on carefully mimicking background lighting conditions to help render an object invisible, similar to how a chameleon blends in with its surroundings. The rear and front surfaces of an object are covered with a material containing an array of photodetectors and light emitters respectively.
and another 2003 article from Wired
The photodetectors on the rear surface are used to record the intensity and color of a source of illumination behind the object. The light emitters on the front surface then generate light beams that exactly mimic the same measured intensity, color and trajectory. The result is that an observer looking at the front of the object appears to see straight through it. -
DUPE! (kinda, sorta)
Very cool story. Be even cooler if I hadn't seen it before. Right here. And it's a 'merican whose applied for the patent.
The idea of an "invisibility cloak" has made the leap from science fiction books to an international patent application. Ray Alden of North Carolina is attempting to patent a "three dimensional cloaking process and apparatus" for concealing objects and people (WO 02/067196). -
Re:Cool!From the pictures on the site, I imagine that they are just going to make a full piece of cement to your size specifications insted of you buying a whole bunch of smaller blocks and cementing them.
No, this picture clearly shows bricks. However generally cement isn't going to be a problem for this material. You can see that he's running fibres from one site of the concrete to the other. The light you see on one side appears in the position it fell on the other side, (look at the two shadows of the woman's right arm - the one cast outside the block is lower than the one cast through the block).
This being the case,you can create room for a channel of cement between blocks by bending the fibres, while having the blocks appear to be flush on the outside. ie:|upper______block|
|/////CEMENT\/<--- fibre bends round channel
|___/________\___|
|lower//////block|| ////////////////| -
Pocket projectors from other projects
Optics.org had an article
this summer about a pair of other pocket projector projects. These includes using an array of lasers to limit scanning or a single higher powered light-source. If 'pocket' is the only thing that matters you might also look into a development of normal bar-code scanners. -
Re:Mirror Site
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Re:Mirror Site
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Re:Mirror Site
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Re:Mirror Site
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Mirror Site
Mirror posted here.
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Re:Cutting patterns in cheese, not slicing it
For an informative post it's got too many factual errors.
:) The laser actually was not used to cut dinosaur patterns, it's what the customer said they want to ultimately be able to do. And "numbers" are not mentioned anywhere in the text. The only example mentioned is the University of Wisconsin-Madison motif (with a picture). -
Re:Stopped photonsWrong. Here's a paragraph from here:
"Earlier experiments on the storage of light stored only the 'signature' of the light pulses in a process somewhat similar to creating a hologram," said Bajcsy. "There were no signal photons present in the medium when the light was being stored. Our experiment, on the other hand, 'traps' actual signal photons inside the rubidium vapour in such a way that the overall signal pulse does not travel."
They are quite literally stopping the light.
Photons are quanta of energy; they are quite incapable of being split or combined. Consult your local library for books on quantam physics...
You'd go to the public library to learn about physics? No wonder your understanding is so botched and incomplete... I suppose you think what happened in this experiment is a figment of everyone's imagination? Quantum electrodynamics predicted that photons can split decades ago, and now they've done an experiment to prove it.
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A few more details
This article gives a few more details, and here is the actual press release.
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Here's another article on it w/picture
Here is another atricle about it that includes a picture of the display. This one isn't Slashdotted.
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Cellophane wraps up 3D displays
Here's a short but decent article on the same research.
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I trust its more inventive than this...The site's slashdotted.
So I didn't RTFA.
I'm assuming its similar to this
.I just hope the solution was more inventive than doing the old theatrical movie stunt about using relative shifting of color information and celluloid glasses - which gives you depth information at the expense of color information. Spy Kids 3D just did this using a blue or green image for the left eye and a red image for the right.. That one's been around since the 40's. In both movie and book. Cute trick but it gives me headaches to see it for any length of time.
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Laser powered rocket
This microwave rocket sounds totally pussy compared to the frikkin LASER powered rocket I saw on Discovery (or was it TLC? I never watch TLC anymore since it's all Trading Spaces now.)
Anyway the laser "rocket" is actually a very lightweight aluminum puck about a foot in diameter, with a some funky curves. They shoot high powered laser pulses up its ass and that superheats the air underneith it, the expansion of which propells the rocket upwards. The pulses fire at about 500Hz so the damn thing sounds like a pulsejet. But at last check it reached an altitude of 71 meters and a flight time of 12.7 seconds. Microwave rocket eat your heart out! :) -
Re:Heh
For your first point go here this is a news article from half way through 2000 for a DVD sized disc that holds 36GB of data - about the time when DVDs became mainstream.
As for the compression, MPEG-2 is 6.25GB/3 hour movie and Div-X is 1.25GB/3 hour movie in same res (if I remember the figures right).
CDs don't have the highest quality of sound, and a surround sound CD would be nice, but it doesn't really make too much of a difference.
On another note, have you heard Human Nature sing ACDC's TNT? Or Legs? Or G&Rs Sweet Child of Mine? It's an experience, look for Musical Challenge. -
I can come close
Before I start, I'm not sure you want a true sphere. It seems that such a design would make you move your fingers a very large distance to hit the proper key, and when pushing down, would get a narrow hole, easy to accidently push another key. This would also necessitate large gaps between keys, or else the keys would ram into each other when pressed (unless flexible keys or some wildly different approach was taken).
It seems like a better idea would be making the *interior* of the ball be the keyboard, have a hole for your hands, and possibly make the thing transparent. It'd minimize hand movement -- your hands stay in one place, and the keyboard spreads out from that point. Hell, heat the sphere and you can avoid those cold "typing fingers" in the winter. :-) That being said, lets see what I can do for you.
First, you could use this, this, or this slid at such an angle that the keyboard approximates the sides of a sphere.
Second, you could use one of the many keyboards that look like this and wrap it around a spherical object.
Third, if you want something with serious hack value, modify a idea like this to work from the angle needed to be typing on a curved surface. -
Re:AmazingNot trying to whore Karma, but check out the small 1 GB disk at these links: here and here.
In addition to LEDs and data storage, GaN based devices have tremendous potential in communication (cell phone base stations), space electronics, compact UV photodetectors, high power microwave integrated circuits, power electronics, medical devices, etc. (Sh*t, this stuff seems to be coming from my thesis-writing mode I'm in.)