Slashdot is powered by your submissions, so send in your scoop

 


Forgot your password?
Close
typodupeerror
×
Displays Portables Hardware

Using Cellophane For 3D Displays On Your Laptop 217

Posted by Hemos from the pop-up-ebooks dept.
prestidigital writes "From the abstract: [the authors] present a novel, inexpensive, stereoscopic technique for generating 3D displays from cellophane and a laptop computer screen. (Once again my physnews update sends me email that doesn't suck!)"
This discussion has been archived. No new comments can be posted.

Using Cellophane For 3D Displays On Your Laptop More

Using Cellophane For 3D Displays On Your Laptop

Comments Filter:

  • what? (Score:5, Funny)

    by b17bmbr ( 608864 ) on Wednesday August 13, 2003 @02:56PM (#6688928)
    no duct tape?

  • Cellophone (Score:2, Funny)

    by burdicda ( 145830 )
    Cell o phone ???????

  • Just cross your eyes! (Score:5, Interesting)

    by dschuetz ( 10924 ) * <davidNO@SPAMdasnet.org> on Wednesday August 13, 2003 @02:57PM (#6688939)
    Okay, I just had to respond to this. I've been a long-time semi-dabbler in stereophotography, and naturally anything 3-D related on /. just jumps right out at me (sorry about the pun). This article, while organized in a scholarly-looking fashion, really doesn't present anything new whatsoever. In fact, if I'm reading it correctly, you can achieve exactly the same results with no cellophane at all!

    They talk a lot about cellophane having natural polarizing characteristics (I'd never heard that, but okay). Then they talk about how laptops have polarizers built into them -- sure, I've known that ever since the glasses for Starchaser: Legend of Orin made my digital watch look funky. Where their article breaks down is in the actual application of polarizing technology on the laptop.

    They suggest putting the right eye's image on the left half of the screen, and the left eye's image on the right, then using polarizing filters to ensure that each eye only sees what's appropriate for it. Great. No problem. Except that there is one problem -- when your left eye is looking at the right half of the screen, your right eye is looking there, too!!

    In order for your brain to properly "fuse" the images together, your eyes will have to perform some tiresome calisthenics -- that is, your left eye is going to have to turn slightly right, to face the right half of the screen, while your right eyes turns slightly left. Basically, you're crossing your eyes.

    If you're just going to cross your eyes anyway, drop all the cumbersome cellophane goggles and overlays and crap, and simply look at two images side by side.

    Also, I'm not convinced that placing a polarizer over half the screen wouldn't just turn that half of the screen totally black (as shown in figure 2 of the paper).

    The challenge for 3-D image display isn't blocking the "wrong" images from each eye, it's blocking the wrong images when they're displayed in the same space -- overlaid in a single frame. For that, you need colors (anaglyphic glasses), or polarizing filters (again, though, both images displayed in the same space), or lcd shutters (multiplexing the images in time, rather than in color or polarization). Or you can use a lenticular screen, that bends the images left or right and draws them in a series of interlaced vertical stripes.

    But not what they're suggesting here. It all seems pretty useless to me.

    [obCaveat: "Unless I'm missing the point entirely."]
    • RTA (quoting physnews [aip.org])

      Taking advantage of the fact that light emitted from a laptop display is naturally polarized to begin with, a 3D stereoscopic effect can be achieved by covering half the screen with a cellophane sheet in order to construct orthogonally polarized left and right scenes while the viewer wears eyeglasses holding two polarizers oriented 90 degrees apart...

      • Re:Just cross your eyes! (Score:4, Informative)

        by Christopher Thomas ( 11717 ) on Wednesday August 13, 2003 @03:13PM (#6689095)
        Taking advantage of the fact that light emitted from a laptop display is naturally polarized to begin with, a 3D stereoscopic effect can be achieved by covering half the screen with a cellophane sheet in order to construct orthogonally polarized left and right scenes while the viewer wears eyeglasses holding two polarizers oriented 90 degrees apart...

        You appear to have missed the parent poster's point.

        If the images for each eye are on different halves of the screen, then polarizing is pointless. It removes phantom images, but the phantoms are far away from the real image, so there's no advantage to doing so.

        Polarizing filters, as the parent poster pointed out, are useful when you have both images in the same place on the screen (overlapping). As overlapping images can't be distinguished by position, some other method is needed (polarization, colour, light direction, etc). When the images don't overlap, they can be distinguished without aids (just cross your eyes).

        • Re:Just cross your eyes! (Score:4, Informative)

          by rsidd ( 6328 ) on Wednesday August 13, 2003 @03:23PM (#6689170)
          You appear to have missed the parent poster's point.

          If the images for each eye are on different halves of the screen, then polarizing is pointless. It removes phantom images, but the phantoms are far away from the real image, so there's no advantage to doing so.

          Actually, there's a huge effect in filtering out the "wrong" image from each eye. The eyes naturally focus much better on separate images if there are no clues that they are separate. That's why stereoscopic viewers have a divider between the two eyepieces for "parallel-eye" viewing (you can equally just place a sheet of paper, if your eyes can decouple well enough without extra optics). Note that images meant for parallel-eye viewing will look "inside-out" when viewed cross-eyed.

        • If the opposite images are filtered out, your eyes will cross automatically, because your brain is convinced that they're just focusing on an object that's closer.

          The real problem is that this technique doesn't allow you to have any objects appear to be outside of a wedge with corners at your eyes and the center of the screen; anything outside of this wedge have one eye or the other looking at the wrong side of the screen. So this is great for objects which seem to hit the user in the face, but is not gene

          • Yes, stuff hitting you in the face would be notably limited, but the wedge doesn't stop at the LCD screen---it extends away from you to infinity.

            The effect (and the affect, for you psychologists out there :-) comes from your eyes/brain applying what they know about parallax to the funky display. The larger the shift in position (relative to each half-LCD frame), the closer the synthesized object appears. At some point, the delta is great enough that if you believed your eyes/brain, the object would be b

    • RTFA (Score:3, Insightful)

      by rsidd ( 6328 )
      Except that there is one problem -- when your left eye is looking at the right half of the screen, your right eye is looking there, too!!

      No, because your right eye is wearing a polarizer that blacks out the right half of the screen and lets it see only the left half. See figure 3.

      • Re:RTFA (Score:4, Interesting)

        by dschuetz ( 10924 ) * <davidNO@SPAMdasnet.org> on Wednesday August 13, 2003 @03:31PM (#6689228)
        No, because your right eye is wearing a polarizer that blacks out the right half of the screen and lets it see only the left half. See figure 3.

        Yes, that's true, but your right eye isn't focused on (isn't pointing at) the left side of the screen -- it's looking where your left eye is, that is, at the right half of the screen, toed in to be where your brain knows the screen is.

        So the only way this could work is if you focus your eyes at the center of the screen, and then maybe, your brain will fuse the images into one. Or you'll relax and eventually your eyes will automatically cross to do the fusing for you.

        All this does, as another poster pointed out, is to help to hide the "phantom" images that you'd see, and potentially be confused by, when crossing your eyes. But when looking at one or the other image, the other one will always be a peripheral image, unless you cross your eyes to really focus on that side of the screen.

        In practice, what you'll probably see with this is an image that sort of shimmers half clear and half black, and a near-duplicate of the image just to the side (perhaps one one side, perhaps on the other). I'll bet that actually fusing the images, in practice, will be difficult and not all that natural. They didn't have any photographs of people actually using their proposed apparatus, so I'm wondering if they didn't just come up with a cool idea, and write a paper about it, without actually testing it.

        All questions of image fusing aside, as I also pointed out, I have a hard time believing that the cellophane wouldn't just turn half your screen black.
        • Think of it as just looking at a spot in the air between you and the screen - the object overing in the air between the screen and the observer in the fugure.

          Of course, you could just put the left eye image on the left side and focus on a point behind the monitor as well, but in order to get good image size you'd have to be pretending to look at something pretty far away (or holding your monitor real close).

        • Yes, that's true, but your right eye isn't focused on (isn't pointing at) the left side of the screen -- it's looking where your left eye is, that is, at the right half of the screen, toed in to be where your brain knows the screen is.

          No, your right eye will be looking at the virtual image that is floating in front of the screen, just like your left eye is. When you project both lines of sight, they fall on opposite sides of the screen.

          Actually, it depends on whether the individual's depth perception is

          • Really good stereoscopic systems will have the image focus depth and the image triangulation depth at the same "distance", so that your brain doesn't have to do any extra work to perceive the image.

            They could solve this pretty easily by providing the lenses as a prescription lens that adjust your focus by the average amount required to change your focus to the correct plane. it would still be a bit off for people like myself who tend to sit over twice the average distance from the screen, but it would c

    • Amazingly effective: Animated GIFs (Score:5, Informative)

      by UsonianAutomatic ( 236235 ) on Wednesday August 13, 2003 @03:18PM (#6689123) Homepage
      The challenge for 3-D image display isn't blocking the "wrong" images from each eye, it's blocking the wrong images when they're displayed in the same space -- overlaid in a single frame.

      This animated GIF technique [well.com] showed up on Metafilter a couple of weeks ago, and for me it was one of those "Why the hell didn't anyone try this sooner" epiphanies for me. Yes, the constant jitter while flipping between frames gets old, but not nearly as old as straining your eyes with the 'cross-eye' viewing method.

    • Also, I'm not convinced that placing a polarizer over half the screen wouldn't just turn that half of the screen totally black (as shown in figure 2 of the paper).

      No. The cellophane (which is placed on half the screen) isn't a polariser, it's a half-wave plate. That means it rotates the polarisation of any light passing through it by 90 degrees.

      In effect, they're making the left half of the screen emit light with horizontal polarisation, and the right half with vertical polarisation (or vice versa).

      • No. The cellophane (which is placed on half the screen) isn't a polariser, it's a half-wave plate. That means it rotates the polarisation of any light passing through it by 90 degrees.

        In effect, they're making the left half of the screen emit light with horizontal polarisation, and the right half with vertical polarisation (or vice versa).

        Aha!

        Interesting. Thanks, that helps a little. So, then, we're back to how easy it is for the brain to fuse two peripheral images (or one primary and one really-perip

    • Basically, you're crossing your eyes.

      What would be better would be to find a way to polarize every other column of pixels, so one image is only a fraction of a millimeter offset from the other. On a high DPI display, halving the horizontal resolution wouldn't be that catastrophic...and would be plenty good for wholesome Internet activities that benefit from 3D.
    • Well, the point of the Celephane is to prevent the left eye from seeing the right eye's image, and vice-versa. It's exactly the same as crossing your eyes, but this way you don't get that ghosting effect. But nevertheless, in the end your eyes will hurt and everything is gonna look really close & small.

      So, you're completely right, all this does is make that annoying ghost image disappear. It also makes looking at water hurt your head.

      But they might also be working with paralell projection (where
    • This site [wsu.edu] has some really neat stuff on this.

      Note the "prismatic lorgnettes" about midway through the article which describes a little pair of prismatic glasses designed to trick the eye to view side-by-side images.

    • Re:Just cross your eyes! (Score:1, Interesting)

      by Anonymous Coward
      I've been a long-time semi-dabbler in stereophotography...

      But clearly, you've not studied optics. The article is pretty clear about what is novel and what isn't, and rather than scholarly-looking, I'd say it was, in fact scholaraly.

      In order for your brain to properly "fuse" the images together, your eyes will have to perform some tiresome calisthenics ...

      Ah, no, the whole point is that you'll focus in front of the screen where the virual object will appear, as clearly depicted in figure 1. Because y

      • In order for your brain to properly "fuse" the images together, your eyes will have to perform some tiresome calisthenics ...

        Ah, no, the whole point is that you'll focus in front of the screen where the virual object will appear, as clearly depicted in figure 1. Because your eyes will be crossed, the image to be sent to your right eye will perforce be presented on the left side of the screen, and vice versa for the left eye.

        You've missed something: yes, you'll be focusing in front of the screen on the

    • Ahh... Thank you...

      I see the schooner now.
    • If you're just going to cross your eyes anyway, drop all the cumbersome cellophane goggles and overlays and crap, and simply look at two images side by side.

      Well, yeah. The problem with random dot stereography or just unfocusing your eyes is that it's hard. With random dots, once you have it, then the eyes have something to grab onto, but if you lose your concentration, the brain uses the other 20 methods of determining what your plane of focus should be and snaps you back to reality.

      The purpose behind t

    • The lenticular screen idea is similar to what I thought of when I read about this; one could possibly manufacture a laptop screen with a strip of cellophane over every other vertical column, or possibly alternating columns with each row for a kind of "dithered" effect. This could allow normal viewing of 2D images without glasses, and 3D viewing with polarized glasses.

    • The thing is your eyes do "cross" when you're looking at something close up.

      Try this: hold your finger six inches from your face, with your monitor in front of that. You'll notice that if you close each eye the image of your finger is in front of the opposite half of the screen.

      Now, if you put the cellophane on the other side of the screen, instead of the image appearing between you and the screen, it would be behind the screen.

      It's the same as if you cross your eyes when you look at those sterescopic p

    • Re:Just cross your eyes! (Score:3, Interesting)

      by brakk ( 93385 )
      You've got a lot of responses about what the cellophane is actually doing and random dot stereograph images so I won't go into that.

      Here [3dculture.com] is a site that lets you see what it's like to just cross your eyes with two images displayed on the screen. (just click on the first icon by each pic, the one with the crossed eyes) What you are doing is trying to line up the two images to meet in the middle to make one 3d image. You will also be able to see an image on each side that if you try to look at you will loose
    • In order for your brain to properly "fuse" the images together, your eyes will have to perform some tiresome calisthenics -- that is, your left eye is going to have to turn slightly right, to face the right half of the screen, while your right eyes turns slightly left. Basically, you're crossing your eyes.

      Actually, that's exactly what you do to view a 'Magic Eye' image - and lots of us out there don't find that tiring at all. Bending your eye's 'outwards' is very tiring, but inwards is easy.

      The celloph

  • Good excuse (Score:5, Funny)

    by Anonymous Coward on Wednesday August 13, 2003 @02:58PM (#6688949)
    Dude1: Hey, you been pr0ning again? Dude2: Erm, no way dude! Dude1: So why you got cellophane over your screen?! Dude2: 3D display man, 3d display Dude1: Aahhhhhh

  • great (Score:3, Funny)

    by Boromir son of Faram ( 645464 ) on Wednesday August 13, 2003 @02:58PM (#6688950) Homepage
    I can't wait to try this with TuxRacer.

  • And in case of emergencies... (Score:5, Funny)

    by Black Parrot ( 19622 ) on Wednesday August 13, 2003 @02:58PM (#6688953)

    ...you can rip it off your monitor and use it as an ad hoc prophylactic, if your computer prowess makes visiting chicks hot.

  • Now will be my laptop who will wear the glasses (as is shown in Figure 3), not me!

    But, if things will be like is shown in Fig 4, I have to wear two pairs of glasses for work in 3d?

  • Alternate. (Score:5, Funny)

    by Gefiltefish11 ( 611646 ) on Wednesday August 13, 2003 @03:01PM (#6688975)

    I recommend wrapping the cellophane around your head. It takes very little time after application before things look 3D, an effect that lasts suprisingly long before everything goes black.

  • With some saran wrap and a more robust server... :)

  • mirror (Score:5, Informative)

    by tedtimmons ( 97599 ) * on Wednesday August 13, 2003 @03:03PM (#6689002) Homepage
    My spidey sense tells me that server is about to die. Here's my mirror:



    http://perljam.net/cache/individual.utoronto.ca/ii zuka/research/cellophane.htm [perljam.net]



    -ted

    • Congratulations -- your server is about to join it in death. :)

      For simple, albeit graphics-intensive, non-commercial sites like this, perhaps using bittorrent to distribute a zip of the site would be indicated. (Maybe one day I'll use my super-special subscriber look-into-the-future ability and save the world. Or something like that.)

  • JUST IN.... (Score:3, Funny)

    by smd4985 ( 203677 ) on Wednesday August 13, 2003 @03:03PM (#6689003) Homepage
    Porn companies have decided to ship Cellophane to their customers free of charge. ;)

  • Another idea (Score:5, Interesting)

    by cybermace5 ( 446439 ) <g.ryan@macetech.com> on Wednesday August 13, 2003 @03:07PM (#6689038) Homepage Journal
    I believe displays that use this technique already exist, but couldn't you print a transparency with a special dot pattern, and place it over the laptop screen? The dots would be arranged so that the parallax from your eye spacing would block the pixels that the other eye can see. Laser printers have much more resolution than LCD screens, so you could adjust for the changing viewing angle from the center to the edges of the screen. You'd have to be able to control the distance from the mask to the screen pretty accurately, and there would be pretty much only one viewing position.

  • If you put the cellophane over your face... (Score:1, Funny)

    by Anonymous Coward
    ...you'll see a 3-d star field. But it fades out after a while.

  • for those who care! (Score:2, Informative)

    by Anonymous Coward
    Using cellophane to convert a laptop computer screen into a three-dimensional display

    Keigo lizuka

    Department of Electrical & Computer Engineering
    35 St. George Street
    University of Toronto
    Toronto, Ontario, Canada M5S 1A4
    Abstract

    We present a novel, inexpensive, stereoscopic technique for generating 3D displays from cellophane and a laptop computer screen. Stereoscopy requires independent manipulation of the left and right eye views.1 Our technique takes advantage of two facts; the first is that the light
  • Does this mean that Nokia will come out with a cool new cellophone with one of these 3-d saranwrap displays?

  • better with real polarizer sheets (Score:5, Informative)

    by Anonymous Coward on Wednesday August 13, 2003 @03:17PM (#6689119)
    cellophane has a poor separation quality, i.e the difference between 90 degrees (blocked) and 0 degrees (pass) polarized light is little.

    Real lab-quality polarizer crystals are way to expensive and generally too small for this application.

    however, sheet polarizing material can be bought in photo equipment stores and cut to size with normal scissors. It's more expensive than cellophane but less expensive than lab polarizers and has a quality that is waaaaay better than cellophane. I paid about 15 bucks for 25*25 cm. about 8 years ago in Germany. Hama sold them at the time
  • ... so their burgers don't look so flat.

  • 3d? Try 0d (Score:5, Funny)

    by Lord_Dweomer ( 648696 ) on Wednesday August 13, 2003 @03:18PM (#6689131) Homepage
    Screw 3d. Thanks to Slashdot their site now displays in 0d.

  • I'd hate to have to peel off the melted cellophane from the LCD.

    Alex.

  • Uh (Score:1)

    by pmz ( 462998 )

    does it work with edible underwear, too?

  • I trust its more inventive than this... (Score:5, Informative)

    by anubi ( 640541 ) on Wednesday August 13, 2003 @03:24PM (#6689175) Journal
    The site's slashdotted.

    So I didn't RTFA.

    I'm assuming its similar to this [optics.org].

    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 [citizen-times.com] using a blue or green image for the left eye and a red image for the right.. [osu.edu] 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.

  • Now that everyone can create 3-D pr0n in the comfort of thier own home, (the cellophane doubles as a great um... contaminant guard)

    ...when do we get the Scratch N Sniff feature?

  • Odd saying... (Score:3, Funny)

    by darkstar949 ( 697933 ) on Wednesday August 13, 2003 @03:26PM (#6689194)
    I guess that this is more proof of the old saying that technology is driven by either
    a) Man's desire to impress women
    b) Man's desire to find a subsitute for women when he is rejected
  • This reminds me of a rather famous April fools joke here in Sweden. Some guy (known for his technical expertise in different matters) said, on TV, that if you put nylon stockings or pantyhose over the screen, you got color TV (this was in 1962).
    • "Some guy (known for his technical expertise in different matters) said, on TV, that if you put nylon stockings or pantyhose over the screen, you got color TV (this was in 1962)."

      I know this bloke. Goes by the name of MacGuyver, right? Same guy once made a laser cannon out of a 9 volt battery, an ice cube, and a kitchen collander. He can use escape from prison using a paperclip, a piece of chewing gum, and the head of an action figure.
  • This idea has been around for years. I first saw in the "Garage VR Handbook", which was published in the early 90's.
  • I've done this before, it really works.

    Just put cellophane over your head, be sure to cover your nose and mouth.

    Stare at your laptop screen and it'll start spinning & rotating. It doesn't work for very long though. My frags dropped after a bit, dunno why.

  • It is only a matter of time before SCTV's Dr Tongue (maker of 3-D House of Pancakes and 3-D House of Beef) sues these guys for prior art.

  • Cellophane wraps up 3D displays (Score:2, Informative)

    by Anonymous Coward
    Here's a short but decent article [optics.org] on the same research.
  • I had this idea myself, actually, but it was stemmed from being pissed off that there was no good, cheap VR headmounted gear.

    I was thinking about using 2 relatively-cheap cellphone LCD displays, mounting them with some lenses, and using that for some nice 320x200-style action. I figure the lcd driver machinery should be cheap and/or have well-enough-documented interfaces, and so wouldn't be *that* hard. Then again, there are many massive projects that were spawned from solutions that were 'not too hard'.

    O

    • using 2 relatively-cheap cellphone LCD displays, mounting them with some lenses, and using that for some nice 320x200-style action. I figure the lcd driver machinery should be cheap and/or have well-enough-documented interfaces, and so wouldn't be *that* hard. Then again, there are many massive projects that were spawned from solutions that were 'not too hard'.

      One of the very first live modern stereo display experiments was done by a researcher at NASA Ames Research Lab in the SF Bay Area, I think about 19

  • It's been a while since I've looked into optics, but with having to basically display the same image on each half of the screen, won't monitors have to become extremely large to make any kind of 3D display worth while? Or is there some special property I'm overlooking that would allow functional 3D displays on todays "small" LCD screens?

    I could see this becoming very useful for building 3D UI's where you could technically stack things on top of each other. Might have to play around with the point-and-clic

  • Why do I need an LCD screen at all? (Score:5, Insightful)

    by raehl ( 609729 ) * <raehl311.yahoo@com> on Wednesday August 13, 2003 @04:56PM (#6689955) Homepage
    Couldn't I just take a regular old CRT monotir, put celophane over the right half to polarize it, then put another pice of celophane over the left half, but rotated 90 degrees, and still end up with two halves of a monitor polarized 90 degrees from each other?
  • I'm completely baffled by what seems like a totally pointless system. If you're going to put a pair of "glasses on the computer," all you need to do is use a pair of lenses that have the right focal length to view the screen sharply, and the right amount of "prism" to provide a comfortable amount of convergence to the eyes.

    This is essentially what the Wheatstone stereoscope--the familiar Victorian parlor stereoscope--did, well over a century ago.

    The cellophane and the polarizers add nothing much useful t
  • MacGyver
  • In other news the gross national usage of cellophane went through the roof this week as thousands of geeks tried to test it's light altering abilities.

    I just threw away a bunch of celophane after tring to get it to polarize or block light from my laptop. Can someone who got this to work a little send me the "oh yeah" clue I'm missing?

    M@
  • The polarization 3D effect causes severe headaches and eye pain in some people. Stick with red/green red/green is your friend, red/green ask for it.

    IcePirates was that stupid, ignorant, lame, ugly flick that used these to steal water from earth when there was plenty just floating around in space. Or something equally bad.
  • Those screen shots look two-dimensional to me.

  • There is a problem if you use polarized sunglasses and your car's lcd display is polarized in the wrong direction. When that happens is that they all appear black and cannot be read. You can use cellophane or some other suitable plastic to "correct" the lcd's angle of polarization and allow the use of polarized sunglasses while driving.


    I'd have posted this info yesterday if I had actually been able to RTFA.

Slashdot Top Deals

In the long run, every program becomes rococco, and then rubble. -- Alan Perlis

Close