this technique has many disadvantages ..

- 2D material looks horrible
- you must keep your head in the same position all the time, meaning that it's probably not good for gaming or watching movies.. (probably not as much an issue for the 3DS, as you can move the device)
- it only works well at a certain distance, you can't sit close or far away
- the 3D effect isn't as good as with glasses

@ Rainbird )

afaik it doesn't work with the existing/coming 3D movies

sounds very costly with 9 layers.

The 3DS should have a similar tech... but definitely not as advanced.

That would have been my guess.

There are implementations that try to track your head. Not sure how mature they are, but I know they're in the research stage.

Well, it's 15º in all directions, so 30º total. Not much room at all, but it IS enough for a few people to fit in front of.

People generally don't view handheld devices at an angle unless the display is being used as a viewer for a digital camera, so this shouldn't be a huge issue. But for anyone who thought they'd be able to see a 3D profile image of the action on screen; you'll be disappointed.

Nintendo isn't using a bleeding edge, just announced display technology for the 3DS; use some common sense. Nintendo always prioritizes cost factors when designing their hardware, meaning they'll use the most cost effective, most readily available solution.

The 3DS is well past the concept and initial design phases, meaning the displays have been sourced for quite some time. Most signs point to Sharp as the supplier for the 3D displays using technology that was introduced back in 2004.

Sharp recently started mass producing these displays for mobile devices (April 2010).

http://www.physorg.com/news733.html
http://www.slashgear.com/sharp-3d-touchscreen-lcd-another-nintendo-3ds-contender-0280110/
http://www.asahi.com/english/TKY201003240434.html

yea, the head-tracking/eye-tracking technique for 3D probably will be the future, but it really needs high speed cams and much processing power (and very good software) for low input lags/support of several viewers

I was listing the disadvantages of the "normal" layer technique

You realize that both the Sharp screens and these new Toshiba screens use the same tech right? They're both paralax-barrier based, the only difference is that the Toshiba screen enables the picture to change depending on viewing angle, whereas Sharps will not. However with use of a camera and face tracking technology, the 3DS will be able to emulate such an effect.

15 degrees in both horizontal directions.  It says nothing about vertical angles.

If they're the same, then the OP should have referenced Sharp, which will likely be the actual supplier of 3DS displays. They aren't the same even though they both use parallax barrier implementation.

I haven't seen any info that clarifies whether the specs on the Sharp displays have changed from the original (2004) 2-parallax to the 9-parallax barrier of the recently announced Toshiba displays, or whether they are separate part lines. There is a significant difference between the two. 2-parallax only shows the 3D effect with a left to right shift in perspective. The Toshiba shifts in 9 directions.