In the patent application, Sony outlines the concept as:
"A method for determining an orientation of a photosensor of a controller with respect to a projector is described. The method includes generating, by a beam generator of the projector, a beam. The method further includes modifying a direction of travel of the beam using a micro-electro-mechanical system (MEMS) mirror that moves in a pattern, deflecting the beam, calculating a time at which the beam is detected and determining based on the pattern and the time an orientation of the beam to determine the orientation of the photosensor."
While it may sound confusing, it is basically outlining a similar device to what the Vive utilises — a beam projector that determines the player's position in the play-space based on light and mirrors (similar to the way sonar works). For those who do not know difference between an external system such as then HTC Vive, compared to what PSVR has built in; it all comes down to immersion. At present, the PSVR employs a built-in system that relies on light from the headset and the PlayStation camera to place the player in the virtual world, offering little mobility for the player.
While there are downsides to an external tracking solution, the key point is it would be more accurate, and would place the PSVR in the same league as the Oculus and the Vive. While the PlayStation 4 may not match the power of a gaming computer with the latest technology, it would at very least give developers a similar toolset when porting games.
It's unclear if Sony plans to use this patent with the technology that is already present in the PSVR, or if this is part of a plan for a PSVR 2, but it is great to see Sony pushing forward with VR, and not letting it die on the bush as many other projects have in the past. PSVR launched the fall of 2016, with overall good sales when compared to the Vive or the Oculus, but as of yet, have not managed to reach mainstream appeal.