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Communications Technology

Collimating Semiconductor Lasers Without Lenses 136

Posted by kdawson from the should-make-somebody-rich dept.
An anonymous reader writes "Researchers at Harvard University and Hamamatsu Photonics have found a way to collimate lasers without lenses. In the new 'plasmonic collimator' technique, grooves are etched directly into the semiconductor laser's internal mirror. This results in surface plasmons giving rise to constructive interference, eliminating the need for the bulky optical lenses that usually focus the light from semiconductor lasers. The technique has promise for steering laser beams without moving parts and for working with polarized light."
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Collimating Semiconductor Lasers Without Lenses More

Collimating Semiconductor Lasers Without Lenses

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  • what... (Score:2, Funny)

    by clone53421 ( 1310749 )

    no sharks?

    • Re: (Score:3, Funny)

      by IdeaMan ( 216340 )

      That joke has jumped the shark.

      • In Soviet Russia ... (Score:1, Flamebait)

        by PPH ( 736903 )
        ...the shark jumps you!

        • Re: (Score:3, Funny)

          by BitterOldGUy ( 1330491 )

          ...the shark jumps you!

          Sweeeet! Shark sex!

          • Re: (Score:3, Informative)

            by sm62704 ( 957197 )

            Wikipedia says [wikipedia.org]... er, actually no, it doesn't. The only mention I could find of the word "Sex" in its article about sharks is an occurance of ASEXUAL reproduction (i.e., virgin birth).

            It only mentioned the "Jesus Shark". Fish generally don't copulate like mammals, but instead the female lays eggs and the male then ejaculates on the eggs. I'm not sure if sharks reproduce like this, but if so, well, if the shark jumps you you will get laid -- TO REST.

            I think the goatse site has an article about bestiality wit

          • If I were a shark you'd already be dead...

          • Re: (Score:2)

            by bucky0 ( 229117 )

            Chuck Norris uses live sharks as condoms.

      • Re: (Score:2, Funny)

        by Anonymous Coward

        I think you mean it has nuked the fridge

      • At least let him have this one during Shark Week.
      • See, I'm only really worried about sharks in a water situation. If I saw a shark on the street, I'd be like "What? Fuck you." It's the opposite of how I feel towards lions. </lovingly ripped off from Demetri Martin>
    • This technology is incompatible with sharks.

      FTFA: The latter could be used for homeland security and environmental monitoring applications.

      Sorry, they're going to use this to find your sharks. Study this and develop some defense for your poor,cute, cuddly little sharks.

      • I don't see how homeland security and environmental monitoring applications are in any sense incompatible with sharks with freaking laser beams... in fact, both the DHS and the EPA would probably be better off if they had more of those! (I'm pretty sure I'd be worse off, though...)

        • I don't see how homeland security and environmental monitoring applications are in any sense incompatible with sharks with freaking laser beams... in fact, both the DHS and the EPA would probably be better off if they had more of those! (I'm pretty sure I'd be worse off, though...)

          You see, homeland security will have that tech and therefore, will be able to track it.

          As far as EPA is concerned, well, if they find that you're abusing your sharks, they'll come down hard on you! I mean, there are work rules - even for evil geniuses such as yourself. Excuse me, I didn't mean evil, I meant morally and ethically challenged geniuses.

          • Oh good heavens, you thought I'd be using these sharks? I swear I was planning all along to hand over the technology to the DHS, no really! What on earth would I do with sharks and lasers anyway?...

    • It hasn't even been tagged lasers...

  • It may be very cool (Score:4, Funny)

    by BadAnalogyGuy ( 945258 ) <BadAnalogyGuy@gmail.com> on Tuesday July 29, 2008 @12:12PM (#24388155)

    But can you hammer a 6 inch spike through a board with your penis?

    • Yeah, you know. What else is there to say about this. It is pretty nifty of course. Small lasers, probably cheaper to make as well, cool, that can well be a very profitable spin-off. The biggest disadvantage of the technique is that it is near to impossible to explain someone what a surface plasmon is ;) No, I won't try.

    • Re: (Score:3, Funny)

      by trongey ( 21550 )

      I don't plan to try without it.

    • Re:It may be very cool (Score:5, Insightful)

      by dgatwood ( 11270 ) on Tuesday July 29, 2008 @12:49PM (#24388749) Homepage Journal

      Amazing. A reference to a relatively mindless comedy (Austin Powers) gets modded up, while a reference to a really good geek movie (Real Genius [imdb.com]) gets modded down as off topic. *sigh* Kids with mod points, I tell ya.... Bets on whether the person who modded the parent down had been born yet when this movie came out? :-)

      • Re: (Score:3, Informative)

        by AKAImBatman ( 238306 )

        Welcome to today's Slashdot. Mindless fools that are 15 years old. The 80's? Don't even remember 'em!

        Or maybe it was always that way and we older folks just don't have the time to invest in shaping this community anymore and thus it has become a haven for the newcomers. Oh, and get off my lawn! :-P

        "Put simply, in deference to you Kent, it's like lasing a stick of dynamite." --Chris Knight

        • Hmm... in hindsight a better quote might have been:

          "I think the young people enjoy it when I "get down" verbally, don't you?" --Dr. Meredith

        • Re: (Score:3, Funny)

          by Lisandro ( 799651 )

          Welcome to today's Slashdot. Mindless fools that are 15 years old. The 80's? Don't even remember 'em!

          Sheeze, relax. We're getting of your lawn already.

    • Come on, offtopic? Real Genius anyone???? Totally on-topic and funny to boot.

    • Not right now.

  • Umbrella funding (Score:5, Interesting)

    by philspear ( 1142299 ) on Tuesday July 29, 2008 @12:15PM (#24388213)

    The latter could be used for homeland security and environmental monitoring applications.

    I don't know much of anything about physics research. Here in biology, if any aspect of your research has applications to cancer, you talk that connection up, even if it's somewhat tenous. There's a glut of funding available for cancer wheras there's substantially less for equally important medical research on aspects of biology "lay people" don't understand. A lot of research funded with cancer research money really has very little chance of actually taking steps towards curing cancer (which is not to say we shouldn't be funding those projects.)

    Is "homeland security" the equivalent of that for physics research? Show a link as to how your project might be used to prevent terrorism and you'll get a blank check from the government? I sincerely hope so, at least some good can come out of our paranoia.

    • I don't know much of anything about physics research. Here in biology, if any aspect of your research has applications to cancer, you talk that connection up, even if it's somewhat tenous. There's a glut of funding available for cancer wheras there's substantially less for equally important medical research on aspects of biology "lay people" don't understand. A lot of research funded with cancer research money really has very little chance of actually taking steps towards curing cancer (which is not to say

    • Physics has a lengthy history of being funded by military operations. For example, the laser itself stems from research into radar guided bombing systems for the military.

      http://www.bell-labs.com/history/laser/ [bell-labs.com]

    • Is "homeland security" the equivalent of that for physics research?

      Short answer: yes. Longer answer... oh wait, some guys with a black van are at the door, I'll be back in a minute.

    • Re: (Score:2)

      by drolli ( 522659 )
      Well - yes and no. Pne thing is - physics is usually concerned about better sensors. While car industry denfine that they want cheaper sensors, medical systems require the best sensors (to lower radiation etc..), security application demand new sensor types. Thats because you can protect a weapon against beeing seen on a 50 year old x-ray, because you can buy a device and test his technique. using new, non-generally available sensing techniques will protect against that.

  • The researchers claimed that if they can achieve a fully collimated laser, it will lower the cost of communications lasers by eliminating the need for lenses while enabling long-range chemical sensing. The latter could be used for homeland security and environmental monitoring applications.

    I don't remember laser sensors being a pressing need for defense of the motherland. Am I downplaying the risks here? I can only imagine that cheaper components will make total surveillance even easier.

    • You mean other than "enabling long-range chemical sensing", like inspecting suspicious boats and cargo from aircraft or other boats?

      You have a problem on seeing how that might help secure our ports from chemical attack?
      • Actually, the most pressing sensor application for the DHS is explosive detectors at airports. The big "puffer" devices they introduced are an utter failure; the "stand still for 30 sec" is an impossible hold-up in security line processing. Anything you can use for spectroscopic identification of chemicals without the need for contact gets funded.

    • Re: (Score:2)

      by Sj0 ( 472011 )

      Well, the truth is that if homeland security was half as important as people say it is, our army, which is better funded than the next 20 largest armies on earth combined, would be at home protecting people instead of in Iraq and Afganistan killing people who probably couldn't point to America on an unmarked map.

  • Disc size reader? (Score:5, Interesting)

    by courteaudotbiz ( 1191083 ) on Tuesday July 29, 2008 @12:23PM (#24388363) Homepage
    I guess this kind of advancement could give birth to disc-sized BluRay or DVD readers, since it is probably, along with the DC motor, the biggest moving part in a DVD assembly... Good for the laptop and ultraportable industry!

  • Back In My Day (Score:4, Funny)

    by Anonymous Coward on Tuesday July 29, 2008 @12:25PM (#24388393)

    We didn't have solid state lasers, you had to bring your own tank of CO2 and a Xenon flash lamp to get the thing pumping. You had to adjust your mirrors with a micrometer. muttering to myself... "damn smartass kids" as I wander across the room to get my Geritol.

  • Hologram (Score:2, Interesting)

    by PPH ( 736903 )

    Is this basically the same effect used by those cheap laser pointers to project cute pictures instead of a simple dot? For $10 I bought such a pointer that included about a dozen interchangeable tips. Each contains a tiny plastic film (a hologram) that shapes the beam into a cute symbol (arrow, smiley face, etc.).

    It sounds like what is being proposed is a hologram (basically a kind of diffraction grating) etched directly onto the die surface. Not a bad idea, but not really new. Unless you want to share you

    • Re: (Score:3, Interesting)

      by jellomizer ( 103300 )

      But that is with a lens. What they are doing is with plasma. So it can be controlled without moving parts. In theory with that you have a program that follows your eyes. then using these lasers they can shine the image and hit the right cells for realistic holodeck like images.

    • Re:Hologram (Score:5, Funny)

      by badboy_tw2002 ( 524611 ) on Tuesday July 29, 2008 @12:52PM (#24388775)

      Dear PPH,

      I am a scientist on the team mentioned in the article and I just wanted to say that you, sir, have rocked my world! I just went down to the mall after reading your comment, and bought one of these "laser pointing" devices. And holy shit, you were totally right! There is absolutley nothing unique or different with the research I've spent 7 years of my life on. This cheap $10 plastic toy is exactly the same thing as an laser built into an IC without a lense or moving parts. EXACTLY the same. I mean, they're both totally like lasers right? Mind. Fucking. Blown. Anyways, the guy that sold me the device is keeping quiet in exchange for top billing on the article in Science, and a piece of the sweet sweet Nobel prize money.

      Anyways, next up for me is taking the $10 plastic toy (because, after all, my research is completely useless as you've pointed out) and integrating it into a quantum computer. Refocusing the laser at quantum scales at the speed required to run a quantum computer can easily be achieved by swapping plastic tips on the end of the pointer (a process we've dubbed "rejiggering the doohickey" in science speak).

      Thanks, and God Bless for pointing out the errors of my way. Guess I need to spend less time in the lab and more time in the mall!

      Sincerely yours,

      Prof. T. Barnum Humperdink III

    • In some sense, yes, it is related to those holograms. They are indeed patterning the facet surface to project a desired pattern.

      One difference is that they are using "plasmonics" instead of holography/diffraction. This means they are using metals (materials that conduct electricity) instead of dielectrics (materials that don't). Plasmonics is more challenging, but offers the potential to create smaller (subwavelength) devices.

      Whether or not they are using diffraction or plasmonics, this is useful because

      • Re: (Score:2)

        by PPH ( 736903 )

        But is plasmonics a new phenomena or just an explanation for how diffraction gratings (and holograms) work? Did the idea of using a grating to focus light occur as a novel idea following its study (it doesn't seem so to me) or does in explain how an idea already used in a $10 toy 'might' be used for something more useful?

        • As I mentioned, plasmonics is different from diffraction, because it involves metals.

          When dielectrics (non-conductive things like glass) react with light, things are fairly straightforward. These materials have a well defined index that you can plug into Maxwell's equations to get your answer.

          With metals, things are more complicated because the metals absorb the light creating currents in the surface of metals. These currents are immediately re-radiated back out (with some absorption). The modeling is in

  • That's nothing. I just found a way to frabjimate SUPERconductor lasers without lenses.

  • Translation: (Score:3, Informative)

    by Tanman ( 90298 ) * on Tuesday July 29, 2008 @12:29PM (#24388449)

    "Researchers at Harvard University and Hamamatsu Photonics have found a way to collimate lasers without lenses. In the new 'plasmonic collimator' technique, grooves are etched directly into the semiconductor laser's internal mirror. This results in surface plasmons giving rise to constructive interference, eliminating the need for the bulky optical lenses that usually focus the light from semiconductor lasers. The technique has promise for steering laser beams without moving parts and for working with polarized light."

    Translation for people like me: Smart dudes at the #1 school and a lab with lots of funding and laserbeams found a way to fire said laserbeams by shaping the mirror instead of having a flat mirror and firing it through a shaping lense. This is good 'cuz now they will be able to do stuff they had a hard time doing before.

    • Re:Translation: (Score:5, Insightful)

      by f8l_0e ( 775982 ) on Tuesday July 29, 2008 @01:05PM (#24388993)
      I don't know what's more sad.

      1. Someone dumbing down a tech article for the slashdot crowd to read.

      2. Said post getting modded up as informative.

      Welcome to the new slashdot. Striving to be more like FOX news every day.

      • Look on the bright side, you can sit there on your high horse looking down on us and smile sadly, confident in your own superiority.

        • Re: (Score:1)

          by f8l_0e ( 775982 )
          I claim no superiority. I do however find it disheartening that people on a site catering to GEEKS need to be spoon fed a tech article. When I read something I don't understand, I look into it further. I don't wait for someone else to explain it to me.

          <quote>Translation for people like me: Smart dudes at the #1 school and a lab with lots of funding and laserbeams found a way to fire said laserbeams by shaping the mirror instead of having a flat mirror and firing it through a shaping lense. This is

      • Re: (Score:2)

        by Tanman ( 90298 ) *

        Many articles on slashdot are not tech articles. Also, among those articles, very few deal with nuances of laser technology. I'd go so far as to say that most articles on programming, robotics, etc, have nothing at all to do with lasers, plasmons, constructive interference, or many of the other things listed in that summary. To most people, that article reads like this:

        Harvard & lab has lasers blah blah blah blah lasers blah blah lense mirror blah blah aim blah blah blah vaporize from space blah blah

      • Well maybe you should spend more time learning Optics and less time picking on informative posts.

        What the parent poster was saying is that the "brilliant" scientists, took a mirror and turned it into a mirrored fresnel lens (i.e. a flat lens). So the laser isn't exactly without a lens, they just incorporated the lens into the mirror.

        Also, I've built lasers and the lenses used in lasers aren't what I'd call bulky. After all you can buy focused lasers that fit on key rings. I've built one using a bullet shell

    • Re: (Score:2)

      by sm62704 ( 957197 )

      I don't think that's correct. You know the flat fresnel lenses [wikipedia.org] they put on rear windows of minivans, and make into credit card sized magnifying glasses you can stick in your wallet? This is about not only using the same technique as a fresnel lens instead of a conventional lens, but what's more doing away with the lens entirely by putting the grooves directly on the laser's rod.

      • Re: (Score:2)

        by Tanman ( 90298 ) *

        It is still reshaping the mirror rather than using a lense -- shape doesn't just mean making it concave/convex. If they add a surface texture such as grooves/etc, it is still altering the shape of the mirror to refocus light rather than using a secondary lense to refocus the light.

    • Translation for people like me: Smart dudes at the #1 school and a lab with lots of funding and laserbeams found a way to fire said laserbeams by shaping the mirror instead of having a flat mirror and firing it through a shaping lense. This is good 'cuz now they will be able to do stuff they had a hard time doing before.

      That's a pretty accurate description. I'd just point out that it isn't so much shaping the mirror as it is patterning the mirror. The mirror is still flat, it just has parts of it etched away.

  • Steering laser beams (Score:5, Interesting)

    by clone53421 ( 1310749 ) on Tuesday July 29, 2008 @12:38PM (#24388561) Journal

    I'm a little curious... TFA didn't really clear this up much. It sounds like they've managed to focus the laser without needing a lens, which is definitely geeky enough to warrant notice... good stuffs like "interfere constructively" and "plasmonic collimator effect" are always fun.

    I am a little bit perplexed, though. They're apparently using etched grooves to induce electromagnetic interference which results in better polarization/linearity of the emitted light. What I don't understand is how this could be used to electronically "steer" the beam. It sounds to me like it can only be used to point the beam in one static direction. The article mentioned a "spatial emission pattern", but I'm really not sure what that means in English...

    They seem to be excited over the fact that no moving parts are involved, which also puzzles me. The lens in a stationary laser isn't a moving part, and it sounds like they've found a technology that replaces the lens. A laser that could be aimed, though, required moving lenses/mirrors... returning to my original question, I'm curious how they're going to "steer" the laser without moving parts.

    Finally, I'm really not sure what they mean by this statement:

    The researchers plan to etch concentric circular grooves in an attempt to fully collimate the laser beam in all directions.

    Isn't that kind of contradictory? Like saying "we intend to fully polarize the light in all directions"? You can't have partially polarized light, and you can't have partially collimated rays... that's like saying you have somewhat parallel lines or a slightly rectangular square...

    • Re: (Score:2, Informative)

      by Osurak ( 1013927 )
      Sounds a lot like a phased array radar: http://en.wikipedia.org/wiki/Phased_array [wikipedia.org]. You can steer beams from those without moving parts, too.

    • The article is misleading. They etched a single pattern in the facet, so the beam is always steered in one direction. With multiple lasers and facets the could choose different directions, I guess.

    • I don't understand it completely either, but if you skim: http://en.wikipedia.org/wiki/Phased_array [wikipedia.org] you may get a better idea of what they meant by no moving parts. I believe that that was referring to aiming the beam by changing the phase angle between adjacent parts, and the concentric circular grooves would allow them to aim it in 2 dimensions rather than just one (perpendicular to the grooves). I could have completely misunderstood it though.

    • Re:Steering laser beams (Score:5, Informative)

      by smaddox ( 928261 ) on Tuesday July 29, 2008 @01:49PM (#24389695)

      If you know the wavelength of a beam of light, you can use interference effects to direct it. This group's current laser uses parallel etched lines to collimate the beam in the Y direction. By switching to concentric circles, they can collimate the beam in both X and Y directions.

      You CAN have partially polarized light, though. Daylight is partially polarized. If you hold up a linear polarizer to the sky, it will be slightly darker or lighter depending on how you orientate it.

      You can have partially collimated light, too. In fact, you can never have completely collimated light. Light tends to spread out the farther it travels. This is usually attributed to diffraction, but in reality they are both results of the true behavior of light - which is modeled by quantum electrodynamics.

    • The researchers plan to etch concentric circular grooves in an attempt to fully collimate the laser beam in all directions.

      Isn't that kind of contradictory? Like saying "we intend to fully polarize the light in all directions"? You can't have partially polarized light, and you can't have partially collimated rays... that's like saying you have somewhat parallel lines or a slightly rectangular square...

      Yes, you can have "partially collimated" rays, as you put it.

      Without collimation, the rays spread out in a cone-shaped beam. In the way described above, the rays are probably collimated in only one axis, so that the cone is "squeezed flat" into a planar angular sector, so now the rays are all parallel to one plane.

      If they were also collimated in the other axis, then the sector would be "squeezed" into a pencil of rays, all parallel to a single straight line.

    • I'll admit to not being entirely sure what a plasmon is, but I suspect it is controllable by electric fields. The article gives the impression that they are trying to find a groove pattern in the mirror such that the plasmons can be adjusted to various patterns by regulating voltage to a few lumps of nearby conductor.

      • Surprisingly, my bio degree actually helps here. A plasmon is a portion of an EM wave that extends beyond it's carrier. It is directly related to the EM wave itself, but it's coupled to it, not a part of it.

        If you bounce a IR beam through a prism, you get total reflectance, with no IR extending through the back end of the prism. However, if you apply a material to the back of the prism, it's presence can mess with your IR beam. This is the principle behind Attenuated Total Reflectance (ATR) Spectroscopy.

        W

    • Re: (Score:2)

      by sadtrev ( 61519 )

      Raw Diode Lasers produce a highly elliptical output which makes it inefficient to couple to a round fiber. It is possible to reduce the astigmatism with fancy lens designs, but this needs to be very close to the die. Even then, the output won't be anywhere near as clean as a gas laser.

      This development sounds like a neat and robust way of doing what had previously be done with carefully assembled, and glued lens - pinhole -lens arrangements.

  • Sounds Fishy to Me (Score:4, Funny)

    by repetty ( 260322 ) on Tuesday July 29, 2008 @12:42PM (#24388631) Homepage

    I didn't RTF because... "plasmons"?

    Sounds fishy to me. Sounds like something a Jedi Knight uses.

    • I believe "Surface Plasmons" were either a rock band or the bad guys from a Dr Who episode.

    • Re: (Score:2)

      by sm62704 ( 957197 )

      I didn't RTF because... "plasmons"? Sounds fishy to me. Sounds like something a Jedi Knight uses.

      Wikipedia says [wikipedia.org] "In physics, a plasmon is a quantum of a plasma oscillation. The plasmon is the quasiparticle resulting from the quantization of plasma oscillations just as photons and phonons are quantizations of light and sound waves, respectively. Thus, plasmons are collective oscillations of the free electron gas density, often at optical frequencies. They can also couple with a photon to create a third quasi

      • FWIW, Fresnel lenses don't rely on the phase addition/cancellation physics that can be demonstrated by a diffraction grating. From reading the article, it looks like what they're using is definitely closer to a diffraction grating than a Fresnel lens.

  • Lightsaber! (Score:4, Interesting)

    by salec ( 791463 ) on Tuesday July 29, 2008 @12:46PM (#24388701)

    Ever since I watched Star Wars for the first time, I had this idea: if I could rapidly move common focal point of thousands of tiny laser beams along the fixed segment of handle axis, with constructive interference (mostly) sustained, with lasers' wavelength matched to a line of absorptive spectrum of atmospheric gas (on Earth it would be nitrogen), I would have a plasma weapon (or tool) very much resembling a lightsaber.

    It should also have adaptive (microcomputer controlled) focusing, so that if any obstacle enters the "blade" segment, all the lasers immediately keep focus on the point of contact, to make it yield to blade as fast as possible

    Now, there is a way to it. I imagined some piezoelectric-actuated mirrors would do, but had no idea how to construct it. This new thingy is so much better and more fine-grained.

    • Re: (Score:2)

      by smaddox ( 928261 )

      That's an interesting idea. Although, you would just be wasting energy ionizing air. So really, it would be just for show.

      That, and it wouldn't reflect ray gun beams - one of the coolest aspects of the lightsaber.

    • A very similar idea occured to me and I did some research into the feasability. I was less interested in the weapon/tool aspect as in the holloween costume/special effects aspect of a simple, low res, 3D display. It turns out there is a Japanese company that is developing a 3D display based on the same concept. The problem is that it makes a popping noise as the air rapidly heats and the process also releases other, more dangerous, bands of energy besides just the visible spectrum so you and any bystander

      • Re: (Score:2)

        by ErikZ ( 55491 ) *

        Are you seriously asking people to not go on violent rampages with imaginary laser weapons?

        If I were going to do such a thing, a chainsaw would be more within my budget.

  • Roger Crossbow, the rabbit is in the hole... (Score:3, Funny)

    by Tumbleweed ( 3706 ) * on Tuesday July 29, 2008 @12:54PM (#24388811)

    Now all we need is a large spinning mirror...

  • That summary sounded exactly like the rockwell automation's advertisement.

    http://www.youtube.com/watch?v=PtuqjFf7-N4
  • This results in surface plasmons giving rise to constructive interference...

    Surface plasmons... that's what Dillan and Troy used to generate a feedback loop in the Cylons in that episode of Battlestar Galactica 1980.

  • You can achieve the same effect by inverting a lateral undefined cloud. If we use the inertial containment nacelle to align it with the primary undefined coil, then by modifying this cargo flux bay, we can make it work in conjunction with the acute plasma procedure. I believe that this will increase the efficiency of the primary deflector undefined by 16 percent. Thus reducing the load on the optical isolinear plate.

    Hey, makes about as much sense as the article's existing intro blurb.

    • Re: (Score:3, Insightful)

      by sm62704 ( 957197 )

      Translation: instead of a conventional curved lens, they use a fresnel lens. This allows them to carve the lens directly into the laser, make it flat, and possibly tune it.

      You're at slashdot, where occasionally you're going to run into some articles that are writen at a postgraduate level instead of the eighth grade level sanity would logically insist on.

      I once read a paper that used the word "enumerate" five times in a single paragraph, and didn't once use the word "count". The submitter could have communi

  • Guess what I got in Google [google.com]:

    A dog's wife.

    So this about frikkin' dogs with frikkin' wives with frikkin' laser beams attached to their heads?

    • Re: (Score:2)

      by sm62704 ( 957197 )

      It means having the photons all travel in the same direction, rather than scattering. Non-solid state lasers are naturally collimated. With those lasers you need a lens to see a hologram, as you need the beam to be wider.

      Look it up on wikipedia.

  • because this might greatly simplify beam combination and steering. A 100 x 100 array of 10 watt lasers (total size, say, ~ 2 ft. on a side) would give a 100KW beam in the far field, steerable at electronic speeds. Yeah, dumping the heat will be problematic, but that's what diamond heat conduction components are for.
  • When focusing a laser through a lens, some of the energy in that laser must inevitably be lost due to the lens not being %100 transparent (invisible). I wonder just how much energy is lost in the lens?
  • Well, my first thought was "bad news for Nikon [nikonprecision.com]"

    That, plus the possible development of various "bug eye" type non-lensed photography [stanford.edu] methods could be bad news for the long-term viability of lens manufacturers. It may be sort of like Kodak in the early 90's- the vast majority of their profits came from film, and it was obvious film was rapidly heading towards obsolescence. The verdict's certainly not in yet on lenses the way it was on film. But what do you do, if you're a giant, successful corporation, but
  • I welcome our new plasmonic collimator overlasers!

  • ... has to clean it up.

  • Typically this is the trend isn't it?
    Collimating Semiconductor Laser Lens Workers will find themselves out of a job. Many will be forced into retirement, some retrenched and a few having to retrain to something like a Semiconductor Laser's Internal Mirror Groove Etcher instead; which is probably exacting and difficult manual labour.
    I mean they already are being teased by other departments aren't they? being called "Collie Maters"
    Geez! I already feel sorry for them.

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