Autostereoscopic small & mid size displays

 At the Emerging display conference is San Jose, 3M discussed their new technology for creation of small to mid format (under 10″) stereoscopic 3D displays. They brought a working sample of a 9″ digital photo frame that had an autostereoscopic, glasses free, display. The display was capable of displaying both 2D and 3D digital images, and were shown in an alternating manner on the prototype.

The technology that is used is called directional backlight. Rather than using a standard 60hz lighting and data rate, it requires a 120hz lighting and data rate. The doubled rate, allows for displaying a left eye and a right eye image in the standard display time. In the case of still photos, the data for the frame is loaded and then illuminated with the left eye light and the right eye light, directing the appropriate image to the viewer. The system synchronizes the side based lighting with the appropriate image (left or right).

directional backlight 3D

3M has created a 3rd generation, 3D enhancment film.  The second generation product that is currently in production and usable for displays from 2″ to about 5″, with the 3rd generation being available in 2011 and supporting up to 10″ displays. The film can be operated using LED edge lighting to perform the alternating illumination. The advantage of the film, is the display can be full resolution in both 2D and 3D mode, and it supports a large view angle as the full screen image is displayed at all times. This means, that there are no “dead spots” in viewing the display as appear in lenticular and paralax barrier displays.

3M Enhancement Film

The film is targeted towards several handheld products and digital picture frame products in the near term future. These devices, have full depth 3D as captured by the cameras and the stills being displayed rather than a “Nintendo 3DS” style depth adjustment.  Unlike prior films, this product is projected capacitance compatible, so it can be used with touch control products.  At this time, the film is not compatible with resistive touch systems that use a standard silver coating – it requires a clear overlayer only. Although it has the higher power form factor, the first generation applications will be a battery based product and still support the alternating of the  two light sources, the higher brightness and a 2X refresh rate.  There are traditional wall cord based applications also in progress.

This solution is a valid one for consumer product use, as it has minimal impact on the need for additional pieces required to view 3D vs 2D, maintaining brightness of the 3D images near levels of the 2D images, and maximization of single user view angle.  For professional use, the film is also compatible with shutter glasses as a solution.

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