It seems like Sony is going all out with their push in to VR technology, as they reportedly announced an in-house engine designed strictly for their VR endeavor.
In a thread posted on Neogaf, Sony London showcased at a GDC session the project running under the name LSSDK. The engine was built from scratch, with some tech shared with other companies.
The engine will use Voxel-based global illumination called Lightfield. If you're confused on what a voxel is, think of them as being physical points in space you can see. They can also serve to decrease graphics acceleration requirements. The problem is though, if we want to fill our screens, voxels either need to be very big or there needs to be a lot of them.
Sony will also utilize a Resolution Gradient technique as reported at the session. This will supposedly save upwards of 25% GPU power. At last weeks GDC, Valve presented a technique that was much the same, but Sony's will feature a way to mask the pixels by applying temporal AA through a shifting pattern.
It was also confirmed that Sony renders up to 1.3x the screen resolution akin to other VR hmds.