New head-mounted displays (HMDs) are revealed on a near-weekly basis, so it’s become hard not to operate under the preconceived notion that they’ll mostly be a carbon copy of the Oculus Rift or Google Cardboard. Tarring Stanford University’s Light Field Stereoscope with the same brush would be foolhardy however, as for once we come across a HMD that is positively striving for innovation.
The HMD itself is bulky and uncomfortable. Poorly designed for everyday use, however to judge it on these merits is to miss the point entirely. The Light Field Stereoscope is an innovation in the visual presentation of virtual reality (VR) experiences, and though it may still be some way from becoming a standardised piece of the technological puzzle of HMDs, it’s a sign of good things to come.
If you couldn’t guess from its name, the Light Field Stereoscope is intended to improve the stereoscopic displays used in HMDs. By ‘improve’, the technology is designed to directly tackle the issue with focal points that occur with the single-screen HMDs that are coming from the likes of Oculus VR, Sony Computer Entertainment and Valve/HTC. It does this by layering two screens one behind the other.
This isn’t a simple case of borrowing from anaglyph 3D with a separate image for each eye, the Light Field Stereoscope instead renders an image out to booth screens and allows your brain to interpolate the images itself. The differential is that of where the eye is able to draw focus: typically the user can only focus on the screen and not specific objects as there is no distance between the objects drawn upon it, however with the Light Field Stereoscope the user is able to adjust their focus between near and far objects as there is added depth given that they are presented on separate screens.
The difference between the stereoscopy in Stanford University’s Light Field Stereoscope and a more familiar HMD’s stereoscopic 3D display is subtle, as it should be. It’s not a forced or mechanical action to adjust your focus: it’s as natural as doing so outside of a HMD.
The software used to demonstrate the differences is well presented but decidedly limited. A series of static 3D models are available for the user to scroll through using the RB button on an Xbox 360 control pad and pan using the left and right analogue sticks. Furthermore, the user could flick between a traditional stereoscopic 3D view using a single screen and the Light Field Stereoscope view by simply pressing the A button.
The software was a precise showcase of the differences between the two forms of stereoscopic 3D, however it also highlighted how underdeveloped the technology currently is. Developers are currently struggling to deliver high quality visuals rendered twice at a constant 90 frames-per-second (fps), with the Light Field Stereoscope renders the frame rate dropped to 25 fps; a decidedly uncomfortable performance.
Stanford University’s Light Field Stereoscope is an important step for VR HMD technology. The subtly in the difference between focal points highlights just how much closer to natural sight the technology can bring VR experiences and will surely become standardised in HMDs a few years from now. However, at this point the technology is limited by the graphical capabilities of the hardware surrounding it, and is likely to be for quite some time.