18-Inch 3D LCD Screens

Rob Polyn sent in a story about a new 18" LCD screen using DTI to simulate 3D. An excerpt describes the technique: "The second approach to true 3D animation is known as autostereoscopy (which DTI monitors utilize). In this method, two solid and unyielding images are produced for the user to view. These images are merged together, and if viewed by one eye, will appear to be two overlapping images, which don?t quite merge together correctly. However, when viewed with two eyes, autostereoscopy can produce vivid lifelike 3D images."

Other 3d Technologies?

This kind of display effectively displays a stereo pair without the need of special glasses etc. Every example I have ever seen requires the viewer to be in a relatively constrained angle to the monitor to receive a true effect. The best 3d I have experienced was a pair of polarized projectors (one horizontal, one vertical) with a passive set of polarized glasses, a camera would track the viewers motion and redraw the scene appropriately, the affect was very much like looking through a window.

Does any one know of any other 3d visualization system being developed, any links would be most appreciated.

Medical Difficulties Have Resulted ...

Unfortunately, this concept has proven to create problems for individuals prone to epilepsy or similar medical conditions. The chance of exciting or aggravating a condition such as this increases if the images are of an autostereoscopy, but are also flashing. Another area of concern is that it seems to cause headaches in many individuals, also.

The goal would be creating a system capable of delivering images to multiple viewers at their respective locations. Current technologies allow a single viewer with a 30-degree viewzone. This may or may not be practical with the current design. Also, another hurdle is producing full color 3-D and proper occlusion (depth cue allowing an object in the foreground to block the ones behind it).

Thanks.


Domenic R. Merenda
Director of Strategic Business Development
BeOpen.com

Spendy

$11,000? Yikes!

LCD is gonna be cool. My dream is for a hardware standard puts 12" LCD displays in the stores for cheap, like $100 or less. Each of these LCD displays could function as an independant monitor, but the coolness would be that you could take the plastic edges off and expose the LCD going all the way to the edge, and there would be an androgynous connector running down each side that could plug into another identical LCD. Take four of these and plug them together in a square, and you have a 24"x24" monitor. You could go out and buy a couple panels every paycheck until eventually you were satisfied with the size or had a monitor-wall to run Quake on.

This would work for TVs as well, and could really make it easier to get big TVs without needing to spend so much money at once.

Just an idea...

Hmmmm...

I wonder how these work for people who are cross-eyed?


thank you.

Something doesn't add up....

In this method, two solid and unyielding images are produced for the user to view. These images are merged together, and if viewed by one eye, will appear to be two overlapping images, which don?t quite merge together correctly. However, when viewed with two eyes, autostereoscopy can produce vivid lifelike 3D images.

That's just not an explanation. But, I figure, it's just a review by some graphics fans. So I checked the company's website [dti3d.com]. (Which barely works. A peek at the image directory got me this [dti3d.com]. I guess we know they're hosting on a Mac, huh?) Their FAQ [dti3d.com], in response to "Q: I am wondering how your display works?" links to http://www.dti3d.com/dev/ [dti3d.com], which is not especially useful. I downloaded the developer's package. The readme says:

dti_vw libray diretory has source files for our driver.
dti_vw app directory has sample file for how to use our libray in a application program.
Our library is so simple and easy to use.
There for this sample is good enough to know how our library works.
Our library make a application can communicate between a computer and our unit.
If we change our the communication method and way, we will update immediately.

I gotta be honest: This all looks pretty sketchy. Has anybody seen/used one of these? I'm not convinced that this thing is legit. I don't have the skills to be able to read the code to figure out how all of this works. But "view with two eyes" just ain't gonna cut it for this crowd.

-Waldo

Re:I don't get it.

I followed some links that were posted in other comments and found the name of the technology that is used. I had saved an old article which described the technique, but I forgot where I got it.

It works with backlighting. There is a striped mask over the lamp, and the lamp is positioned a little distance behind the liquid crystals. If you draw a lines in 3D space from a light stripe to each eye, each line will pass through different pixel elements on the way.

a better explanation of how it works

i read their review and they really don't explain how it works. yes, i know steroscopic vision is one of the many techniques used to create a 3d effect inside the brain, but how does it work? how do they make sure each eye gets a separate image?

after a little more research i came up with this Philips research paper [philips.com]. (be sure to look at the nice diagrams in the slides).

the gist of it is this: much like 3d postcards, they use a grid of cylindrical lens over the LCD panel. each lens covers a specified number of real LCD pixels, 4 being a common number. since the lens is constructed to have the LCD pixel be at the focal point, when you look at the screen through the lens your eye will be directed towards one of the 4 pixels and not the others. thus the lens has turned 4 real pixels into one 3d pixel. (and dropped your resolution to 1/4th!) if you shift your viewing angle then you will look at a different one. if, like many people, you have two eyeballs which are separated by a few inches, then each eye will see a different image.

another way of thinking about it is to imagine that four zones of images are being projected out from each pixel to your eyes. as long as your eyes are in separate zones then you are okay. this is the case if you are sitting at normal reading distance. but if you get too far away (or have a head the size of a mouse) then your eyes will end up in the same zone and you lose the 3d effect.

philips has also done some innovative work to even out the resolution loss and improve the viewing angle.

- joshy

after reading how it works i now understand why it's so dim. if there is a 4:1 ratio of real pixels to 3d pixels, then each eye is only getting 1/4 the light it used to. guess they are going to have to beef up that backlight. then you can switch back to 2d and have a blinding image reflect of your face, just like in the movies. :)

I dread the coming psuedo 3d wave ..

.. as I am blind in one eye. As well as fearing wearable computers for the same reason. How many other "disabled" people out there wonder how we will adapt to the toys of the "perfects" in the future of computing???

Not TOO limited.

However, I imagine it is a fairly restrictive veiwing angle and thusnot that great if you want to show something to others.

It's not all THAT bad. (If this is what I think it is) there are a SET of narrow angles from the screen where the stereo effect works correctly.

They're bisected by another set of angles where the depth is reversed, and the space between the clean images (normal or reversed depth) has regions where the two images wash into each other.

So a person can sit closely beside you (distance from your right eye to his left is one, three, five, etc. times the distance between your eyes) and simultaneously see the same image.

The main problems are...

- You have to be at distance from the screen equal to a constant times the spacing between your eyes (plus or minus maybe 20%) to get the effect. At the wrong distance the images for each eye also bleed into the other eye, giving you a triple image - the one you want, plus two single-eye ghosts.

- Images TOO far ahead of or behind the screen will give you eyestrain - because your eyes have to focus at the distance to the screen, but the paralax depth cue says the object is far from the screen. So your eye muscles hunt and get tired.