Can the VR craze and new display technologies save 3D TV?

Can the VR craze and new display technologies save 3D TV?

After nearly a decade of promoting 3D as the next great thing in television, most of the industry has moved on to promoting 4K, richer color, flatter screens, and clever applications instead. But the flame hasn’t entirely died, and a combination of new technologies for glasses-free 3D and a coming boom in 3D source material driven by the craze for virtual reality (VR) experiences might just be enough to resurrect it.

The Holy Grail: Ditching the glasses

The need for special, sometimes-expensive, glasses to view TV in 3D is the most-often-cited reason for its failure in the market. Lack of source material has also been a major issue. Ironically, the companies pouring billions of dollars into various not-quite-ready or on-the-drawing-board VR products have doubled down on the need for glasses — their solutions all require even more onerous and expensive goggles. Beyond hard-core gamers, many of whom will put up with ungainly VR headsets to get the benefit of immersive gaming, it’s not clear how many users will put up with the inconvenience of headgear — although much like the IMAX franchise, there will be a niche market in immersive experiences using those same headsets.

The premium price of the needed hardware and immersive content is appealing to companies seeking desperately for profitable products. That — along with the gold rush of companies including Facebook, Google, Sony, Samsung, and others competing to dominate this nascent industry — is beginning to drive massive content creation. In addition to new startups like JauntVR, relative veteran companies like Lytro are re-purposing their technology to help creatives djinn up VR content.

For those of us still not willing to wear a heavy and disorienting pair of goggles to experience our entertainment, that leaves the door open to repurpose all that amazing VR content onto our TVs and computers. However, the benefit of the immersive experience will be completely lost if our TVs aren’t at least 3D-capable — it would be like trying to watch an IMAX movie at home. So expect these same companies to start looking around to see if they can restart the 3D TV market using newer technology to provide a compelling glasses-free experience.

There are a number of trends moving in their favor. First, instead of having TVs that needed to split a 1080p HD signal across the two eyes — or by even more than that to support multiple viewing positions — we’ll be working with 4K and even 8K systems that have a lot more resolution to sacrifice. Dolby even has a system that it claims allows full-resolution to be sent out to both eyes. Second, autostereoscopic (glasses-free) 3D displays continue to improve. There are several new approaches that might make it to market in time.

Tricking your eyes into seeing 3D with tensor displays

Just like compressive sensing cameras, that appear to be able to gather more data than their sensor can capture, compressive displays use advanced math to display different high-resolution images to different viewers at the same time without needing a much higher resolution system. The most advanced version of these are what Stanford professor Gordon Wetzstein calls tensor displays — which were originally prototyped at MIT’s Media Lab. These displays incorporate several layers of LCDs over a light source. By factoring  3D source material into components that can be displayed sequentially at high frequency on different layers, the display shows viewers what they would be seeing if they were looking at the 3D scene from their perspective. Watched at full speed these displays look nearly like a hologram. The magic is revealed when you look at a tensor display in slow motion. It looks like a changing pattern of near-gibberish. When these displays can be made thin-enough, and high-resolution enough, they may provide an excellent solution to the Holy Grail of glasses-free 3D TV.

Tensor displays rely on a lot of advanced math, but this video from MIT provides a good overview of how they factor a signal into components that can be displayed on each of several layered LCDs so that they can modulate a backlight to create the appearance of a 3D image from several different viewer positions:

Advances in microlens-based displays

The other major approach to 3D displays that support multiple points of view — for TV viewing, many viewpoints need to be possible, not just the two eyes that might be enough for a smartphone or laptop — uses tiny microlenses to project different versions of the image to each viewing position from each “pixel.” To date, microlens technology has greatly limited the viewing angle of these displays, but research hasn’t been standing still. Recent prototypes have substituted small spheres for the microlenses, allowing for lower-cost, wider field of view, displays.

More radical are the hologram-like systems that use projected light to create a 3D effect. Currently they are very limited in size, like the Leia system, or very expensive like the model from Holografika. But recent work that extends tensor display technology to work with projected light sources might be a sign that we’ll eventually have high-resolution projected 3D images.

Maybe 3D TV will happen, but not on your TV

The biggest reason 3D TV is hard is because it needs to support a wide viewing angle, potentially with many people looking at the image from different perspectives. For small-screen, single-person, viewing, parallax barriers provide a relatively-low-cost and simple solution. A filter is placed over the display that allows half of the pixels to radiate towards the left eye, and the other half to radiate towards the right eye, in alternating columns. Then 3D source material has each channel projected onto the appropriate pixels. This technology is used in autostereoscopic (glasses-free) 3D smartphone displays like the Nintendo 3DS. With an increasing amount of movie and video content being consumed on the small, personal screens of phones, tablets, and laptops, it will be much easier to provide a satisfying glasses-free 3D experience. That alone may be enough to rekindle excitement in the 3D entertainment market.

Dolby, Philips, and James Cameron all say it can happen

In the meantime, Dolby Labs has partnered with electronics giant Philips and megahit Director James Cameron to provide glasses-free 3D TV solutions for content creators and device makers alike. Their system can encode either native 3D content, or 2D content rendered into 3D for viewing on glasses-free displays. Cameron has a long track record for being a stickler for high-quality when doing 3D projects, so his backing means that the effort is worth watching. Despite several licensing deals, no device maker has yet been able to ship a set that actually delivers the technology to consumers yet. Other solutions that seem to be perpetually on the horizon include Ultra-D, which has been licensed by TV-maker IZON for its upcoming product line. Ultra-D uses microlenses to divide an image into portions for each of several viewing positions, similar to the monstrously expensive Toshiba “Naked-Eye” 3D TV. LG also aims to have sets similar to its CES-demo prototypes on the market within a couple years.

Unfortunately, the concept of glasses-free 3D TV has been like Lucy holding the football for Charlie Brown — a perennial promise that has yet to live up to the hype. But once the dust settles on 4K TV, and that upgrade cycle is finished, expect the industry to dive back into providing 3D solutions full steam to continue to fuel its growth.