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Toys Science

Laser Pointer Holograms 124

Posted by michael from the things-to-do-when-you-tire-of-playing-with-the-cat dept.
kgb1001001 writes: "A couple of instructors at Lake Forest College and the Kyoto Institute of Technology have put together a nice little page on amateur holography using laser pointer diodes. This home-page gives enough information to get started and also includes an order form for the photographic plates and chemicals needed to develop the holograms. Also, another page discusses the same techniques and materiels, but comes with some nifty pictures (2-d of course) of the final outcome."
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Laser Pointer Holograms More

Laser Pointer Holograms

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  • Too expensive (Score:5, Interesting)

    by BillyGoatThree ( 324006 ) on Saturday December 29, 2001 @09:14PM (#2763748)
    Laser pointers? Film? Chemicals? BAH!

    Draw them by hand [amasci.com] using a compass and plexiglass.

  • A lot of companies, sports teams, and record labels for example, have started using holograms as a certificate of authenticity and now that Everyday Joe can make holograms with a few supplies they will have to find something new to spoil the deeds of counterfeiters.
    • The reflection holograms described in the article require a very bright light source to properly view the image. They are very far removed from the commercial mass-production processes in use today.

    • Re:Counterfeits (Score:3, Interesting)

      by checkitout ( 546879 )
      The type of holographic labels companies use are completely different from what is being described here.

      The process being discussed uses glass plates, chemical developer and is monochromatic. The type of holography you're refering to uses micro embossed metal to produce an image.

      I dont think they have anything to worry about. :)

      Anyway, we did this for a science class in college, and it was a lot of fun even though the image of my pocket watch came out kinda dim. You need an object with a really reflective surface to get something sharp looking, plus a steady hand and a room with solid floor. There's a lot of variables to account for and a lot of people simply ended up with a glass plates with some cool looking lines on it.

    • Re:Counterfeits (Score:2, Informative)

      by capsteve ( 4595 )
      the holography that tj describes on his web page is a denisyuk or on-axis reflection hologram, done with a low powered laser on to silver halide based film. the holography that is being used as anti-counterfeiting methods(credit cards, cd's, baseball cards) are using a variation of the whitelight transmission or rainbow hologram. this method requires(typically) a multi-watt, water cooled argon laser with photoresist plates and a highly toxic development procedure. after a photoresist plate hologram is created, a nickel "mother" plate is grown using a plating process(like for choming). this mother plate is used to grow several daughter plates, which in conjunction with heat, pressure, and hard to aquire materials is embossed onto paper and plactics using a hot stamp process. the manufacture of these kind of holograms is just terribly time consuming, expensive, and spans several old-school technologies(photography, photochemistry, electro-plating, web press, foil hot stamping) and requires a small army of people. the security hologram is only security thru obscurity; the return on investment for the manufacturing of these security items is horrible, and the manufacturing of the materials used is built to order(not many people order tem00, 50 watt tunable argon lasers; photoresistplates; mercuric chloride, potassium permanganate, and other obscure toxic materials). all things which are easily tracked from manufacturer to purchaser.

  • Good article (Score:2, Insightful)

    by puma_duh ( 317981 )
    This is the kind of stuff that should be spread among all students... it's so cool that it makes me puke :-)

    That's the best way to spread the love for science and to make our curiosity take over our minds... that's the kind of stuff that makes the world go forward.

    Well done, keep up the good work!

  • Creating your own . . . (Score:5, Informative)

    by OverlordQ ( 264228 ) on Saturday December 29, 2001 @09:21PM (#2763759) Journal
    Here [hmt.com] is an informative page about creating your own holograms, and the different types.

  • More on Holography (Score:3, Informative)

    by nice ( 144965 ) on Saturday December 29, 2001 @09:24PM (#2763768)
    I knew I'd eventually use those pointers for more than annoying people.

    http://www.shadow.net/~holodi/holobook.htm [shadow.net]

    This seems to be a rather popular endeavor. Further resources:

    http://directory.google.com/Top/Science/Physics/Ed ucation/Light_and_Optics/Holography/ [google.com]
    • This seems to be a rather popular endeavor

      aloty of folks are looking to figure out how to run it in reverse.

      who ever invents the first holodeck gets to make a lot of money.:-)

  • Laser pointer holography was originaly developed by Frank DeFreitas. His web site http://www.holoworld.com/holo/diode.html [holoworld.com] has many pictures of his work. Quite a marvel. You should buy his book. It is very informative. It's about 17 bucks from Amazon.com [amazon.com] Its very helpful and takes you step by step in the process and a bit into the history of holograms etc. I'be had great success with his process. It's a bit harder to find his holographic plates, and this isn't exactly the cheapest thing in the world. The plates cost me US$60 for five or six! But the results are great. You CAN'T use this for any kind of forgery because the holograms are on a glass substrate. I suppose it is possible to put it on plastic somehow. But beats me on how to do it.

    W-S

    • Re:More in laser pointer holography (Score:5, Informative)

      by FTL ( 112112 ) <slashdotNO@SPAMneil.fraser.name> on Saturday December 29, 2001 @11:00PM (#2763904) Homepage
      > Laser pointer holography was originaly developed by Frank DeFreitas.
      > You should buy his book

      Absolutely not. Avoid that book like the plague. The supplier for his plates has gone out of business. The new supplier that took over manufacture of these plates describes Frank's technique as "crap". And it is.

      I made the mistake of purchasing his book and trying to get results. He makes things far far more complicated than they need to be. By contrast, the integraf techiques (as linked to from the main /. article) are much simpler much cheaper and produce perfect holograms. I just finished making some stunning integraf holograms a couple of days ago.

      • > Absolutely not. Avoid that book like the plague.

        Sorry, I didn't mean to be quite so energetic with my comments about Frank's "shoebox holography". He was (acording to him) the first person to use laser diodes. However the fact remains that his book hasn't aged well. As I said before, the main suplier for the plates has gone out of business. And in the mean time other people (such as Integraf) have come up with far simpler, easier and better methods. Whereas Frank uses a creaky assembly of threaded pipes, pipe ends, several spring clips, a lens, and a laser, Integraph gets much better results with just one laser, a clothes pin and a container of salt. Integraf's technique is so good that you don't even need a vibration isolation table!

        Frank's "Shoebox Holography" may have been the bible of laser diode holography several years ago. But Integraf has rendered him obsolete.

  • Did this project last month with my brother (Score:4, Interesting)

    by flxkid ( 171985 ) on Saturday December 29, 2001 @09:34PM (#2763788) Homepage
    It was really quite interesting to setup. The ones we made turned out so-so. The problem was the only room that we had to create the holograms in was on the 2nd floor of the house. So all kinds of vibrations from below caused some problems.

    If ur going 2 do this urself, I'd advise setting up the project in a school's darkroom or janitor's closet with a cement floor.

    Make sure ur far away from streets and all forms of noise (and therefore vibrations) as this REALLY causes problems.

    FLXkid (the Visual Dataflex Guru)
    ...
    Better VDF than VD!
    • My father was playing with holograms with a home made HeNe laser about 20 years ago I think.
      At the time I didn't understand much of the process but I remember he had to borrow a street level place in a low traffic area and had to place the working plane on a stack of strange things such as buckets of sand and tires' inner tubes.
      Doesn't sound too professional but might still work.

      baubau
    • The problem was the only room that we had to create the holograms in was on the 2nd floor of the house. So all kinds of vibrations from below caused some problems.

      Interesting. Maybe the best thing to do is do it outside on a dark night, or in side a light tight bag (like the kind they sell for changing film on medium or large format cameras...or even for 35mm HIE work).

      Make sure ur far away from streets and all forms of noise (and therefore vibrations) as this REALLY causes problems.

      Outside after a long hike into no man's land it is then...at least if holographic plates/film hold a latent image well. If you put one in a light tight bag after you expose it (or leave it in the bag and take the laser out), does the image remain stable until you develop it, or do you need to do that as soon as possible?

  • This is been done for years now. A couple of links. Check the dates. http://www.3dimagery.com/pointer.html http://www.holoworld.com/holo/diode.html Tim Massey Don't say I never gave you anything
  • I actually went to a little seminar one day at the MIT Media Lab where we did this. It was really cool. You can make much more impressive holograms with the right equipment, but the fact that you can do it with a laser pointer and not this expensive monster of a laser is really neat

  • is this going to be a contest (Score:1, Informative)

    by Anonymous Coward
    of who can link the most websites about holograms...cause i just won!

    The holoshop [holoshop.com]

    another page [holograms-online.co.uk]

    yahoo group on holography [yahoo.com]

    the big holobook [shadow.net]

    how to shoot holograms [imagesco.com]

    holoworld [holoworld.com]

    silver holographic [silver-holographic.com]

    holophile [holophile.com]

    the last one but a good one [come.to]
  • Man: Is your uh, is your wife interested in....holography, ay? 'Holographs, ay', he asked him knowingly?

    Squire: Holography?

    Man: Snap snap, grin grin, wink wink, nudge nudge, say no more?

    Squire: Laser pointer diodes, eh?

    Man: They could be, they could be taken with diodes. Candid, you know, CANDID holography?

    Squire: No, no I'm afraid we don't have a laser pointer.

  • Been there, done that, works great. (Score:4, Interesting)

    by FTL ( 112112 ) <slashdotNO@SPAMneil.fraser.name> on Saturday December 29, 2001 @10:50PM (#2763888) Homepage
    A couple of days ago I just finished creating my first set of holograms based on their techniques. And I have to say that it was a lot of fun and turned out quite well. If you've never tried creating holograms, give it a shot. It takes a bit of time, but it is well worth it.

    The only catch is that these holograms are only visible at a very narrow range of angles. Not just the two angles of rotation to your eye, but also the two angles of rotation to the point light source. So it can take a bit of fiddling before you suddenly see something. But when you do, it's very sharp and detailed.

  • Those laser pointers you can get with with switchable tips that cause the device to project different 2D images (by multi-slit-diffraction, I suspect) can be fun. One time I was in a hotel up on the tenth floor and I had just bought one of these toys.

    [Side note: yes, I know this is somewhat off topic, but this thing I'm about to tell you could have amplified effect with 3D projections.]

    I stuck on the tip which projected a 'UFO' image, stepped out onto the balcony and shone it onto the ground. I moved it around and after a few seconds I heard some little girl scream "MOMMY!" so then turned it off. Imagine what you could do with one of these things projecting the right 3D image ... fun!
  • That I can finally custom-make my holo-friend? I've always wanted a friend, but hologram technology hasn't caught up with my needs. Geeks have needs, too!!!
  • I'd probably be the smart ass that would creat a hologram of the windows 2000 cd.

    (you know, the one with the hologram on it?)

    Would that be like putting mirror in front of a mirror?

    Anywho, off to bed....

    .
  • ...Yet another thing those annoying teenagers can do with this annoying pointers at the movie theaters...

    When will those guys STOP?!?!

  • Pointer? Pointless! (Score:3, Informative)

    by tcc ( 140386 ) on Sunday December 30, 2001 @01:12AM (#2764085) Homepage Journal
    Get a used HeNe laser off ebay or any Optics surplus, with TEM00 properties (which means the laser is coherent... needed for holography, and you'll be able to make some holograms that have more than a few millimeters of coherence (hense, depth).

    Laser Diodes holography really sucks, it's pricey for the result you get, learn the thing with the right basic parts. If you're ready to invest let's say 400$ worth of chemicals films and all, with the idea of doing more in the future, might as well invest in the proper "amateur equipment"

    Also: High power laser diodes in a decent spectrum (630-640nm) aren't THAT powerful, or if they are, (more than 5mw) they are pricey. These laser diodes lacks coherence (notice how close are the object from the plates). Without coherence, you don't get depth, without power, you have more chances that your object might move (if the object moves just a quarter of the wavelength, it screws up the hologram), so getting a cheap used 20mW HeNe laser gives you the benifit of power (you won't make a 8x10 with that, unless you have a really stable environment that can take 30+seconds exposure time depending on the object, of course doing the hologram of a fruit might not work too well with that much exposure because only the "fermentation" of the fruit over 30 seconds changes the structure in the nm scale :), yeah sometimes it's that crazy, I tried :) ).

    The only downside of Gas lasers is their lifespan. You can be lucky and it would last for 3-4 years, like you can get one that will last for 6 months, depends on the manufacturer, prices, condition. Normally they give you the tube usage and lifespan. Also, it requires high voltage power supply, which isn't a problem for the low power heNe lasers (under 30mw at the output).

    Holography is cool, but it takes patience, a lot of trial/error, and when you want to move a step further, it takes as much money than doing high-end photography (with all the optics and chemicals).

    • Re:Pointer? Pointless! (Score:5, Interesting)

      by hyrdra ( 260687 ) on Sunday December 30, 2001 @02:26AM (#2764192) Homepage Journal
      I'd like to make a few comments on your post as one who has been in this field for over five years.

      First, TEM00 has very little to do with coherence properties. It's a type of resonant mode and has more to do with polarization than anything else. A TEM00 laser is not required to make holograms, nor is a polarized laser. In fact, ruby lasers which are not TEM00 and Argons who often mode jump left and right are used very often for holography.HeNe's are naturally coherent due to the spectral output characteristics of Neon, which doesn't change wavelength very well based on temperature or power flux. Diodes, on the other hand, have rated shift in wavelength with temperature and/or power. However, newer power supplies automatically sense changes via a feedback loop photodiode and adjust power characteristics accordingly. A good diode with a digital PSU will give you 12+ feet in workable coherence. Add a themoelectric cooler to stabilize the temperature and you can increase it even more. That being said, I doubt anyone has any use with 12 feet of coherence or more. A polarized HeNe from the manufacture Coherent, for example, has several 100's of yards coherence. But who needs that much, seriously? For doing simple objects, a few feet is plenty.

      Remember, the goal is trying to record the interference patterns of two (or more) beams on a film plate. Light only interferes well with like-wavelengths, so when your diode shifts in the middle of a 40 second exposure, it will degrade the pattern and thus the diffraction efficiency (if a transmission hologram) of the hologram, and thus the brightness -- the rest of the light is loss to scattering. However, with a 50 mW diode you can easily have sub-second exposure times with a 3x4" plate, which should produce a hologram with equal quality as one produced by a HeNe.

      A good test to find out the coherence length of your diode is the classical Michelson Interferometer. It produces controllable interference via a path length delta in one of the optical arms. As long as you can obtain an interference pattern at delta, that is your coherence length. I tested a 5 mW diode from Radio Shack and got around 3 feet of coherence.

      There are many advantages to using laser diodes for holography over the conventional HeNe. First, they're cheap -- much more so in the price/power ratio than a new or surplus HeNe. You can get a complete 50 mW 650 nm laser diode system for around $500. That's plenty of power for doing 8x10's with exposure times in the seconds. Diodes are also small and do not involve high voltages associated with the gas discharge tube-type supplies HeNe's employ. Even a used 20 mW HeNe on eBay (which is very rare) will run you about $700 to over $1k. A new one could cost several thousand. Better to get a multiline argon and do color ~

      I should also point out that you can obtain very high power diodes at around 670 nm -- these diodes produce 1W or more of power and cost only a few hundred. The beam requires a fair amount of conditioning because the emitter is rectangular and thus emmits a beam high in divergence, but an anamorphic prism pair will give you a nice round beam with 1.2 mRad of divergence for miles.

      Another thing to think about it that the HeNe, as a technology, has been around since the late 1960's. It's old and there is no more R&D going on with gas lasers. Diodes, on the other hand, continue to be a very hot materials and science research area. Diodes are getting more stable, smaller, more efficient, and the wavelengths keep going doing (Nichia makes 400 nm diodes now). You can also purchase a diode pumped solid state (DPSS) system to frequency double an IR diode to create useable green output. HeNe's see no more devlopment in these areas and are being replaced by diodes. This actually decreases demand and thus increases price...do the math!!

      Anyway, hope this helps someone. I have been using a TE cooled 500 mW Philips diode with digital PSU built from a PIC, with dual anamorphic filtering. With this setup I am able to create very bright holograms with several feet coherence length...

      At long last -- yes, it is true you can make holograms with a laser pointer!
      • Thanks for the clarification, it was 1am when I wrote this, I might want to add one thing though, the HeNe I got a few years ago were 10mW tubes and PSU for 100$ each, sometimes you can get great deals just by looking around.

        I'm really impressed that you got 3 feet of coherence with Diodes, maybe I should look into testing newer ones as well.

        As for 670nM the hologram won't be as bright as if you would have used 635nM, the higher you go in the spectrum the less sensible it is to the human eye. Or did you test something that contradict this as well? :)
        • As for 670nM the hologram won't be as bright as if you would have used 635nM, the higher you go in the spectrum the less sensible it is to the human eye. Or did you test something that contradict this as well? :)

          Actually if you soak the plate in some post-processor (depends on plate type/manufacture), it will shrink the plate, shrinking the interference fringes and thus lowering the wavelength. This still doesn't get rid of the sensitivity problem (most holographic film is more sensitive to 632.8 nm, the wavelength of a HeNe laser, than higher red wavelengths but it's still perportional), but using this method it is possible to create green and even blue colored holograms by shrinking the plate after exposure with a higher wavelength laser. Some of the green 550 nm holograms I've done are truly stunning in their brightness. If you think of a hologram more as fancy diffraction grating than a picture you can envision some really cool stuff. Try taking a transmission hologram of a lens and then viewing it -- you'll find you have created a holographic optical element -- a diffractive reproduction of a glass/plastic lens which bends light by changes in it's speed, and transformed it into something which bends light via diffractive effects and interference.

          What's really cool is taking a hologram of a telescope or other optical arrangement and then when you look through the lens of the holographic telescope it actually works!

          Optical science is always so fascinating.
          • Yeah I've seen some HOE stuff like you're referring to with the telescope, it's really interresting. You're lacking several diverging lenses? no problems, make an HOE of the lense and stick it back in the optical setup. Of course there's a big loss of power depending on the efficiency of the hologram, but it's still impressive :)

            Of course post-processing the plate is an option that I've completely forgot, maybe because I am more of a "less steps less chances of screwing up" type of person :) for the sensitivity you can always pre-latencify it depending on which type of film used (and of course if the datasheets are representative of the media used, some datasheets seems rather "what you SHOULD expect" from a batch of plates to another :) ).
    • Holography is cool, but it takes patience, a lot of trial/error, and when you want to move a step further, it takes as much money than doing high-end photography (with all the optics and chemicals).

      While I don't completely doubt you, I do want to make sure we have the same idea of "high-end photography".

      Canon has a 600mm f/4 lens and a 1200mm f/5.6 lens. Neither have list prices (well the 1200mm doesn't, I think the 600mm doesn't either). They are not stocked items either. Not just not stocked at camera (even CPS) stores, Canon also does not stock them.

      You call Canon, they quote you a price and build time, and then they make it. Not sure if you pay first, or after.

      One can also spend quite a bit on lights, $400 is on the very low end for a studio light, and some studios use 10+ of them ($200 is a good price for an amature's light, and it might be usable as a hair light to a pro if it is reliable enough).

      Some triggers (sound/laser) are in the $600 range, and fiddling with them trying to find the right delay and distance and sensitivity settings to catch a bullet in flight, or a balloon collapsing, or the like can consume many 36 exposure rolls of film (many pros don't like digital for that sort of work -- I expect they will in a few years though).

      35mm pro film cameras cost $1000 to $2000, digital $2000 (D30 - bad AF for a pro camera, bad flash exposure for a pro camera, bad weather seal for a pro camera, great everything else) to $5000 to $8000.

      Medimum format and large format cameras cost more, depending (actually the Holga 120 costs about $15, but it sucks pretty bad). MF digital scanning backs can cost $50,000 and up (as in $120,000 or more).

      Drum scanners make a Nikon 8000ED seem cheap.

      Cibachromes can approach $100 *per print* from a master printer.

      Is Holography going to run that much? (hmmm, may be time for a second job...)

    • I have used both a 5mw helium neon and a cheapo 3 to 5mw pointer diode laser. The helium neon has been sitting in the closet gathering dust for 8 months. The diode laser has only 5 minutes warm up time, at least 2 feet of coherence length compared to 8 inches with the gas laser. It's smaller, less fragle. Another plus, if your doing single beam holography you can pull the lens off the pointer and the beam diverges with out an extra lens. At least as far as holography is concerned, I think neon helium lasers are going to go the way of vacuum tubes.
  • www.photologie.net [photologie.net] has a geat walkthrough for laser pointer holograms with lots of pictures.

    It covers adding more power to the pointer as well and some details for opening the caseing without damageing it.

    Bust out your Dremel tool and potentiometer, and use the fish [altavista.com] cuz its in French.


  • In a similar vein, I've spent the past week or two trying to develop a way to produce seamless, stereoscopic 3D desktop backgrounds. I've always had an interest in stereography [ibiblio.org], but until now I couldn't find a way to apply it to my PROPAGANDA tiles..

    Just yesterday morning I finally managed to produce (and can reproduce at will) stereoscopic 3D wallpaper in Gimp. No rendering, no photography, nuthin but pure hand-made goodness in Gimp. :) The next best thing to holography, I suppose. :) Have a look here for a small example image [ibiblio.org], or if you have a very large display, you can see the unscaled original here [ibiblio.org]. Just bring it up in any image viewer, or set it as your background..The fun part about it is that casual onlookers look at your desktop and just see a nice background...You would only know it was 3D if somebody told you. :) It doesn't require any special 3D glasses or anything stupid like that -- All you need to do is lightly cross your eyes like looking at the image. Here's a quick lesson in how to see it in 3D -- Sit squarely in your chair a few feet away, directly facing your monitor. Don't look at it at an angle. Cross your eyes lightly until you see "the one in the middle". If you have problems seeing it, hold up a pencil exactly halfway between your eyes and the screen. Focus on the tip of the pencil for a few seconds and whammo, you'll see the background show up in 3D.. When tiled as a background, the 3D effect looks like an egg-carton, or like the sound-dampening walls of a recording studio. Spikes and pits. For added mirth and merriment, swivel in your chair a little bit and you'll see the image move correspondingly. Even more fun, is trying to move back slowly while seeing it. The farther you move back, the deeper the image will appear. I'll probably surprise the gimp-devel folks with an explanation of how its done in a day or two. :)

    Cheers,
    • Have you tried Random Dot Stereographs?

      PersonalPaint on the Amiga can produce R.D.S's.,
      even an Animated R.D.S.

      To the onlooker an RDS just looks like a pattern,
      until you tell the onlooker to look into the
      screen.
    • Actually, crossing your eyes is usually the 'quick' method to seeing the 3d image in a stereograph. Unless the stereograph was designed for this method, it will result in the depth being reversed. Normally you are supposed to set your point of focus beond the image.

      Most printed stereograph's use the 'slow' method.

      (I call it slow, because it is usually harder to set your point of focus FURTHER away than it is to set it closer.)

      Another side effect to using the 'quick' method (besides the image being in reverse) is that the image will appear smaller in size than if the 'slow' method is used. Atleast this is the effect I get :)

      Of course I do do not remember the last time I played with a stereograph... its been a while... However I have tried both of these methods while on the john looking at the tiles at the floor... Have to have something to do when you have nothing to read :)
  • If you built yourself 2 nitrogen lasers (produce UVA light) and you pumped high voltage electricity into them, you will have an electric beam that will shoot a few hundred yards.
    It works because the intense UV light from the laser ionizes the oxygen in the air. Ionized air is more conductive of electricity. The high voltage electricity shoots down the path of the laser beams.
    You have to have two laser beams to have a complete circuit. If you shot this at a deer or somthing, the electricity would travel down one beam, pass through the deer's central nervous system, and pass back out on the other beam.
    BTW, you could set it from "stun" to "kill"
    Also there is quite a few people who build nitrogen lasers. Its not hard.
  • I don't think anyone has mentioned a reasonable way of damping vibrations on the cheap. We set up a cheap optical table (in high school, 20 years ago...) by building a sandbox and setting on four motorcycle inner tubes. That did a good job of minimizing vibration which was important since our exposure times were about 2 minutes with our very weak laser... A nice benefit was that by putting mirrors and objects mounted on PVC pipe tubes, we could use the sand to position things were we wanted them- just ram them in and wiggle into the best spot... Those were the days...

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