One of the key hurdles that desktop-class virtual reality companies like Oculus VR and HTC must overcome is latency, or the amount of time it takes for the platform to register the fact that you’ve moved your head to the moment the display responds to the movement.
If it’s too low, you’ll likely run into motion sickness.
As Road to VR notes, current high-end headsets feature displays running at 90Hz which means they can display 90 images per second. That’s the generally accepted standard today but according to Nvidia’s Vice President of Research, David Luebke, there’s plenty of room for improvement.
During Nvidia’s recent GPU Technology Conference, Luebke demonstrated a prototype display operating at an impressive 1,700Hz which is nearly 20 times faster than what today’s consumer headsets are doing. The prototype was attached to a rail system that rapidly moved back and forth yet due to the high refresh rate, the resulting image was barely affected.
Luebke said they overloaded the display and was driving it with a novel binary delta sigma encoder approach. The executive joked that you could put the display in a paint shaker and it would appear to stay solid, effectively eliminating the display as the latency bottleneck.
With a fast display like this, the bottleneck simply moves elsewhere so you’d need an extremely low latency input to accommodate it. Luebke told the publication that the wheels on the rail system used in the demo fed the movement of the carriage almost instantaneously to the system. Without a low latency input mechanism, the fast refresh rate of the display is essentially useless.
Until we reach a point where latency is lowered across the board, clever tricks like low persistence will have to suffice.
