A new “Direct retinal projector” patent granted to Apple by the U.S. Patent and Trademark Office describes a new system for Apple Glass which will remove the external display screens and project images directly in the users’ pupils.
Cupertino tech giant is reportedly working on augmented reality (AR) and virtual reality (VR) glasses and headsets to allow users to enjoy immersive gaming, training, or other experiences. Based on previously granted patents, Apple Glass will be worn over the eyes for unlocking other devices, video recording, and even displaying an AR keyboard on any surface.
To avoid accommodation-convergence mismatch problems, Apple Glass will be equipped with a direct retinal projector
The filing explains that AR and VR devices display computer-generated images to create an immersive artificial environment that makes users feel that they are physically present in the projected reality. Such artificial reality can be used for virtual training, gaming, controlling drones, watching content, browsing, and more.
However, accommodation-convergence mismatch problems can physically impact users by causing headaches, nausea, or eyestrain. “Accommodation-convergence mismatch arises when a VR or AR system effectively confuses the brain of a user by generating scene content that does not match the depth expected by the brain based on the stereo convergence of the two eyes of the user.” Therefore, the new patent proposes a gaze tracking system in the AR Apple Glass which will detect users’ pupils and will automatically adjust and project images directly in their eyes.
A direct retinal projector may include a gaze tracking system that tracks position of a subject’s pupil and automatically adjusts projection of a scanned light field so that the light field enters the pupil. A control loop adjusts a scanning mirror to substantially center an IR beam on a position sensing detector (PSD). In so doing, the scanning mirror is correctly positioned so that the scanned light field from the projector enters the subject’s pupil.
In addition, a direct retinal projector may include an adjustable focusing element that adjusts focus of a combined light beam generated by a projector as the light beam is scanned to an ellipsoid mirror that reflects the light beam to the subject’s pupil. The focusing of the scanned beam may be adjusted as the beam is scanned across the azimuth angle of the curved ellipsoid mirror.
It is difficult to predict the viability of such a system to project beams directly in users’ eyes and related health concerns to that system. It must be kept in mind that Apple files for thousands of patents annually and does not develop every technology filed in the patents.