Mercedes-Benz Splitview display lets the driver and passenger see different material on the same in-dash LCD, typically navigation for the driver, a movie for the passenger. It's one of the highlights of the 2009 Los Angeles Auto Show, which opened today for press previews. Splitview orients alternating pixels at driver and passenger, so each sees the full center stack screen, 7.0 inches in the case of the Merecedes-Benz S-Class and CL-Class cars that are first to get Splitview. Splitview is based on Sharp's Dual View technology, which has been available to automakers for half a decade. Because the driver can't see what the passenger sees, Splitview should get around state prohibitions on front-seat DVD players visible to the driver when the car's in motion.

I first saw Sharp Dual View at the CEATEC 2005 trade show in Tokyo and was blown away with its potential: Why shouldn't a front-seat passenger have the ability to watch a movie, too? Alas, U.S. automakers didn't have the blinding clarity of vision I had. That or they saw problems not immediately evident to mere journalists:

-- Dual View / Splitview provides half the resolution to each person, so the auto industry's highest-resolution LCD display, the 1280-by-480 panel on high-end BMWs would effectively be a vanilla 640-by-480 VGA for each viewer; that resolution dates back to the mid-1980s on PCs. On the other hand, the pixel density of a display that's 7 to 10 inches diagonal remains pretty high. And it's not hard to jack up the resolution on smaller panels.

-- Special panels and display drivers are required, increasing development costs. Of course, if Splitview sells a few more $85,000 Benzes, you get back your investment pretty quick.

-- Some state legislatures, not thinking ahead to the era of Dual View / Splitview, wrote laws that prohibited video playback in the front seat when the car was moving, as opposed to using their collective wisdom - we are talking state legislature here - to write laws that say "can't be viewed by the driver when in motion." When I previously asked other automakers why they didn't leap to embrace Dual View, they all cited legal hassles as one reason for inaction. Either Mercedes has worked around the problem or realizes it's not a problem for all practical purposes. Think how many portable GPS units technically violate windshield obstruction laws, and how few tickets are written. (The states with GPS-exemption laws often say it has to be down low in the left corner, while most units are centered in the windshield.)

Sharp says Dual View uses a parallax barrier, or mask, that orients the view of alternating pixels left then right, left then right. Splitview isn't like those velvet paintings where, as you walk along, you see Elvis, then Jesus, Elvis, Jesus (that is, where you can see each image from multiple angles). Here the driver sees the left-facing image best when he or she is 30-45 degrees off center; it fades as you move closer to being directly in front of the LCD. To see the movie the passenger is watching, you'd have to move your head over almost to the center of the passenger seat; simply moving your head to the centerline of the car wouldn't be good enough.

Visteon, the auto electronics manufacturer, previously released a back-seat DVD player with Dual View (a lso a replacement in-dash radio / navigation system), but success was limited. One reason is that the trend has been away from a single DVD player / display that drops down from the roof (obscuring the rear view mirror in some cases) in favor of separate screens in the backs of the two front headrests, giving each back seat passenger a display directly in front.

I could see Splitview also being popular in high-end 2+2 touring cars - meaning costly, great front comfort, pretty tight in back - where it's typically two people traveling together. It would also play well in SUVs, crossovers and minivans where mom or dad in the front passenger seat wants to watch the same movie the kids are seeing in back. The long term trend is the same as on airlines: one seat, one display, rather than shared displays. For a lot of passengers, an iPod is the display, although for longer trips, it's easier to jack into a bigger display.

Most automakers (just not the Germans) now lock out access to some navigation commands when the car is rolling. You can call up a preset address at speed, but not enter the address character-by-character. With a Dual View / Splitview display, you could at least allow the passenger to enter a new destination while underway, browse the Web if the car has an embedded cellphone, or find a hotel or restaurant, all without stopping. In a decade, Dual View / Splitview may be the de facto standard display on every car.