Just a few years ago, mobile displays took a leap forward with increased pixel densities that ensure crisp images on realtively small screens. Today, most smartphones feature displays with up to 538 pixels per inch (ppi) – a resolution that is much higher than what the human eye can see. So what’s the next display innovation we can look forward to?
In her recent article on IEEE Spectrum, Sarah Lewin introduced two companies that are working on making what she calls “holographic” light field displays (i.e. glasses-free 3D displays) a reality.
Ostendo Technologies recently presented the results of nine years’ work at the Display Week conference: An array of 4×2 Quantum Photonic Imager chips (each consisting of LEDs, image processors and embedded rendering software) plus microlens array form a 1 megapixel (1024x768px, XGA resolution) prototype display which sends out light not into every direction – like conventional displays do – but rather into very narrow, collimated angles of light. This enables the prototype to emit different images into different directions, producing about 2,500 different perspective views, so the image and motion displayed appear consistent regardless of the viewer’s position. Continue reading →
About a year ago, Nvidia presented a novel head-mounted display that is based on light field technology and offers both depth and refocus capability to the human eye. Their so-called Near-Eye Light Field Display was more a proof of concept, but it’s exciting new technology that solves a number of existing problems with stereoscopic virtual reality glasses.
Nvidia researcher Douglas Lanman recently gave a talk at Augmented World Expo (AWE2014), in which he explained the background and evolution of head-mounted displays and the history and design of Nvidia’s near-eye light field display prototypes: Continue reading →
Today’s glasses-free 3D displays ususally consist of dozens of devices, which makes them not only very complex, but also bulky, energy-consuming and costly. At SIGGRAPH 2014 conference, Gordon Wetzstein and Matthew Hirsch from the MIT’s Camera Culture Group presented a new approach to glasses-free 3D that is based on projectors and optical technology found in Keplerian telescopes. Their novel method for “Compressive Light Field Projection” consists of a single device without mechanically moving parts.
Because it’s relatively cheap to build with today’s optics and electronics, the presented prototype could pave the way for cinema-scale glasses-free 3D displays. Continue reading →
At this year’s SIGGRAPH conference, currently taking place in Anaheim CA, tech blog Engadget spotted an unusual participant in the “Emerging Technologies” section. Douglas Lanman and David Luebke from the research labs at graphics processing specialist Nvidia presented what may be considered a prototype of the future of Virtual Reality: a near-eye light field display.
But what does it do? Microlens arrays, which are mounted just in front of the high resolution displays, are used to convert pixels to individual light rays, thus creating a light field directly in front of the eye. The viewer is thus able to refocus at multiple depths into the scene.
3D displays are slowly moving into mainstream, but most of the technologies used today require the viewers to wear special 3D glasses, or watch from a very defined, small optimum viewpoint. More advanced 3D displays use eye tracking, and create a stereoscopic effect by specifically sending different images to either eye.
David Fattal and colleagues from HP Laboratories in Palo Alto, California developed a new approach to glasses-free 3D displays, which comes with a number of improvements: Their prototype displays use multi-directional diffractive backlight technology, which makes them particularly well-suited for mobile devices (e.g. smartphones, tablets, or watches). They’re high-resolution, very thin (<1 mm), don’t require eye tracking, and feature a very wide view zone (up to 180 degrees) at an observation distance of up to a metre. Their work was recently published in Nature.