Apple has obtained a patent for a VR headset and / or smart glasses that work with a direct retinal projector
Today, the US Patent and Trademark Office officially granted Apple a patent for a VR headset and / or smart glasses that use a direct retinal projector system to resolve the conflict between convergence and adaptation. Apple has been working on it for a few years now. Apple was granted another patent related to this project in September 2021. One of Apple’s first in-depth patent applications covering a direct retinal projector dates back to September 2019. Today’s patent adds to this set of work on a direct retinal projector.
In Apple’s patent history, they note that conventional virtual reality and augmented reality systems can suffer from accommodation-convergence mismatch issues that cause eye strain, headaches, and / or discomfort. nausea. Accommodation-convergence mismatch arises when a VR or AR system effectively confuses a user’s brain by generating scene content that does not match the depth expected by the brain based on the stereo convergence of two eyes of the user.
For example, in a stereoscopic system, images displayed to the user may cause the eye (s) to focus at a far distance while an image is physically displayed at a closer distance. In other words, the eyes may attempt to focus on an image plane or focal depth different from the focal depth of the projected image, thereby causing eye strain and / or increased mental stress.
Hosting-convergence mismatch issues are undesirable and can distract users or affect their level of enjoyment and endurance (i.e. tolerance) of virtual reality or augmented reality environments.
The patent issued by Apple covers various embodiments of methods and apparatuses for providing virtual reality (VR) or augmented reality (AR) systems. Methods of carrying out a direct retinal projector are described which can, for example, resolve the convergence-accommodation conflict in head-mounted AR and VR systems. A VR or AR headset system is disclosed that can include or implement different techniques and components of the retinal direct projector.
Embodiments of a gaze tracking component or system are disclosed relating to a direct retinal projector system that tracks the position of a subject’s pupil and automatically adjusts the projection of a scanned light field generated by a projector component. system so that the scanned light field of the projector enters the subject’s pupil.
In some embodiments of a gaze tracking component, a light source (eg, an infrared (IR) LED) projects an IR beam of light. One or more beam splitters ensure that the IR beam is approximately q at the center of the scanned light field generated by the projector component of the direct retinal projector system.
The projected light and IR beam are reflected by a 2D scanning mirror and the curved ellipsoid mirror before reaching the subject’s eye. Part of the infrared beam entering the pupil of the eye reflects off the retina and exits the pupil (forming a “bright pupil”). The return infrared beam reflects off the curved ellipsoid mirror, 2D scanning mirror and beam splitters to reach a position detection detector (PSD), for example a quadrant cell technology PSD (also called cell PSD quadruple).
A control loop adjusts the 2D scanning mirror to substantially center the return infrared beam on the PSD. In doing so, the 2D scanning mirror is correctly positioned so that the scanned light field of the projector enters the pupil of the subject.
Apple’s patent FIG. 4A below illustrates a substantially ellipsoid curved mirror; FIG. 4B illustrates the light of a curved ellipsoid mirror of a direct retinal projector hitting the pupil at different positions.
Apple patent FIGS. Figures 5A and 5B below illustrate the principle of operation of a gaze tracking system; FIG. 6 illustrates a direct retinal projector which includes a gaze tracking system.
Apple’s patent FIG. 9 below illustrates a direct retinal projector that includes an adjustable focusing lens. The projector # 2004 of FIG. 9 can, for example, be used in a direct retinal projector system as shown in FIG. 6.
Apple’s patent FIG. 11A above illustrates an example of optical actuator # 3020 which can be used as an adjustable focusing element for the beam in the projector.
An example of a system that is configured to implement any or all of the techniques described herein is illustrated in FIG. 12 below. For example, the system 400 illustrated in FIG. 12 can be configured as a virtual reality headset.
Apple’s patent FIG. 17 below is a logical block diagram of a frame for a VR / AR device. The figure shows an example of a system (# 900) including a frame (# 905) that can be configured to contain various elements of a VR / AR device, such as the elements of system # 400 of FIG. 12. In various embodiments, the frame may be an eyeglass frame, an eyeglass frame, a helmet, or the like, configured to be worn on or over a subject’s head so as to position the curved mirrors ( # 415A and 415B) in front of the subject’s left and right eyes (# 990), respectively.
For more details, see the patent granted by Apple 11,157,072