3D LCD's for Sale

Hollinger writes "Dimension Technologies, Inc. has created and is selling LCD displays that yield true 3D images without tracking hardware. 'No Glasses. No Headtrackers. No Eyestrain. No Compromise. No Kidding,' according to their Web site. " I'll believe it when I see it, but can you imagine playing Everquest or something on this thing?

Nothing new.

Ahh, the Russians have had these capabilities for years, its called "clay pottery" and involves the realtime molding of clay by a team of russians who hide behind your monitor.

The U.S. could have had this working long ago if they hadn't cut their spending on high speed kiln research.

Hotnutz.com [hotnutz.com] - Funny

somewhat related...

The Human Interfaces Technology Lab [washington.edu] at U Washington has some cool projects going on.

The one I thought was really neat are their Virtual Retinal Displays [washington.edu] which can scan a 3D image directly onto your retinas using tiny lasers. That would rock for Unreal TE.

numb

Re:Refresh rates + techniques

They say on their products page that they are using a 60Hz refresh rate which is using "LCD technology, which is inherently flicker-free".

Apparently the revie w in [dti3d.com]Machine Design [machinedesign.com] says that "The screen uses a liquid-crystal display and an illumination plate. The LCD generates translucent colors while the plate carries light lines or pencil-thin light generators that run the height of the unit and are spaced on a two-pixel pitch. The plate also holds lenticular lenses that direct light at a slight angle. The LCDs are wired so that every other column displays image information intended for a viewer's left eye and the other columns for the right. In the current design, both halves of a stereo pair are displayed simultaneously. Several people can view stereo images at once.".

This sort of makes more sense if you see the diagrams on the page, but I would have thought that it would require you to be pretty much directly in front of the screen and viewing it at a perpendicular angle, (from a certain distance) otherwise you are going to start receiving the wrong information to each eye.

However, once you have it calibrated for your eye seperation, I see no reason why you shouldn't get really strong stereoscopic images. When's the next trade show near Brussels so I can try it out?

Interesting side point: The press on this form of 3d vision on their web site dates back to 1994 so it's not exactly cutting edge (unless they've recently undergone a quantum leap forwards and I haven't picked up on this from the site).

Patent Searching for Dummies

If you want to know "how it works", you can read their patents.

Instead of giving you a giant results URL, I'll explain how to do it:

• Go to US Patents & Trademark Office [uspto.gov].
• Select Patents.
• Select Search US Patent Databases (it's big, it's red, it likes like a title rather than a clickable item!)
• Select Boolean Search.
• Search for Dimension Technologies in the Assignee Name field (when an engineer works for a company, the usual deal is that the engineer agrees to assign patent rights to the company in partial consideration for the salary they get. The company is the assignee and this is the primary way companies come to own patents).
• Read the patents.

I'm not enough of a hardware guy to understand how this display actually works, but maybe someone here can comment on that!

Seen this at EPCOT Innoventions

I saw a demo of this kind of technology at Walt Disney World's EPCOT Center in Innoventions, at least 2 years ago (probably more like 3).

Hammacher Schlemmer had a booth there, and showed a 3D video of people kyaking down a river. You didn't need glasses, and you had to stand in just the right place to eliminate the moire-like interference effects caused by the way it did the 3D, but it did work.

It was cool, but I'd personally prefer to wear some lightweight 3D glasses rather than ensure I'm always in the exact position to get the full 3D effect. However, I don't know why we haven't seen at least a few of these for sale by now, as I imagine they would have their niche.

heinrich hertz institute

The Heinrich-Hertz-Institute [www.hhi.de] has released some detailed papers about projection technology like this a long time ago. Especially interesting is the proposal for an operating system using the stereoscopic image.

The display [www.hhi.de]
Something about the Operating System [www.hhi.de] for the screen.

press release [www.hhi.de] about all this.


It's from 1997 actually

How it is done.

I saw a demonstration of a simple hack to convert a laptop to do this at a conference a few years back. (Cost: About 15 cents.)

You make a moire plate by hacking up a postscript program to draw thin lines across a page with a spacing of half the pixel spacing on your LCD panel. (Tune the program as necessary to get the spacing right.) Print it on an overhead-projector transparency and mount it over your LCD display.
Each eye sees half the scan lines, with the other half are blocked by the black stripes. One eye gets one half, the other eye the other half.

You typically have to rotate the display a quarter turn, because the typical display has vertical color stripes, so using it in the normal position will give you half the colors, rather than half the scanlines, into each eye.

In addition to having the right spacing on the plate (very slightly closer together than twice the line spacing), and the right distance from the plate to the pixels (which you get by tuning that "slightly" so the plate can sit on the screen, typically with the toner on the side toward your eye), you have to be roughly centered in front of the screen and roughly the right distance from it.

The obvious improvement(which I've been meaning to do for a couple years, if nobody got around to it commercially - and it looks like these guys did) is to replace the flat plastic sheet with light-absorbent stripes with one with triangular and slightly curved ridges - exactly the sort of plastic stuff you see in those thick, non-holographic pictures, some of which are 3-D, others animated-when-you-move-your-head-or-the-picture. This does the same thing by bending, rather than blocking, the light, so you don't have to waste half of it.