Hitting Every Angle with Autostereoscopic 3-D Displays
By Gregg E. Favalora, Optics for Hire
Clever use of electro-optics, lens arrays, diffusers and software advances the multidimensional way of seeing
The broad field of autostereoscopic display – the creation of imagery that appears three-dimensional without requiring the use of additional eyewear1,2 – is evolving. Optical engineers continue to push 3-D display technologies to match depictions in science fiction movies. It’s 2012, after all – can’t one simply buy a “holographic video display” that snaps into a DVI port and generates a cubic meter of full-color, occlusion-bearing, utterly natural imagery?
Well, almost.
There is much to consider in our journey, with 38 species of stereoscopic and autostereoscopic displays in 3D@Home’s taxonomy, and several possible classifications.3,4 (Reference 3 is a recommended starting point for technically oriented newcomers to the topic.).
The 3-D display is just one element of a broad pipeline spanning content generation, or acquisition, to the production of a 3-D image.
What are the aims of current research?
This depends on the particular use of each type of display. A mobile device, such as Sharp’s directional parallax barrier backlighting in the Nintendo 3DS, permits a solitary user to view the display at less than arm’s length, from one constant viewing angle. Therefore, a two-view autostereoscopic image suffices. Contrast this with the aims of research in autostereoscopic television, which might require hundreds of unique viewpoints to numerous simultaneous viewers at various distances and viewing angles or, alternately, some combination of head-tracking and fewer unique views. Finally, consider boardroom and military uses, in which 10 people might encircle a horizontal display that projects volume-filling imagery above a tabletop.
Other than mobile, which I consider “solved enough” because of technologies from Sharp, MasterImage 3D and 3M, the field is experimenting with acceptable solutions for larger displays. Researchers still yearn to combine high-definition (HD) resolution, a natural effect of horizontal motion parallax for multiple simultaneous viewers, and the high-fidelity reproduction of depth both in and out of the display surface. For example, there are many vendors of flat panel autostereoscopic displays for desktop or living room use, but these devices usually are hampered by uncomfortably narrow restrictions on the viewer’s head placement within a viewing zone [more…]
Source: Photonics Spectra