updated 04:36 pm EDT, Tue July 29, 2014
Cascaded display research from Nvidia could lead to cheaper virtual reality displays
High-resolution, low-cost displays for virtual reality headsets such as the Oculus Rift could become a reality sooner than first thought, if recently-revealed research from Nvidia is adopted. Researchers working for the graphics chip producer realized that stacking two lower-resolution panels on top of each other could effectively provide a similar experience to the user as looking at a higher-quality display.
The company tested the theory by acquiring two standard 7-inch 1280x800 displays, reports ExtremeTech, with the LCD panels layered on top of each other with a small offset, effectively allowing one pixel on the top layer to lie above the quarters of four different pixels on the lower layer. A single blacklight was used to illuminate both layers of the "Cascaded Display."
Nvidia then created software which allowed the pixels on the front LCD panel on and off, allowing for only a certain quarter of the lower pixels to be shown. On the second pass, the front panel changes the shown pixels, while the rear changes the panel's colors, and so on, allowing for all of the quarter-pixels to be displayed, and in turn providing a higher-resolution image.
While promising overall, the research does point to a number of drawbacks in the system. Power saved by going for a lower-resolution display may have been mitigated by the extra processing power required to render the image correctly, as well as a need to increase the brightness of the backlight. The process does offer relatively fast refresh rates above 60Hz, though the process may introduce extra unwanted lag, something which can help destroy the effect of virtual reality headwear. Viewing angle limitations may also prevent it from being used on tablets and smartphones, but still makes it viable for head-mounted displays.