Apple won 43 Patents today covering an HMD with a Direct Retinal Projector System and Reflective Holographic Combiner & more
The U.S. Patent and Trademark Office officially published a series of 43 newly granted patents for Apple Inc. today. In this particular report we briefly cover Apple's technology in regards to their future headsets (VR, MR, Glasses) with a Direct Retinal Projector System and Reflective Holographic Combiner and more. And as always, we wrap up this week's granted patent report with our traditional listing of the remaining granted patents that were issued to Apple today.
HMD with Direct Retinal Projector System with a Reflective Holographic Combiner
Apple's granted patent covers various embodiments of an augmented reality (AR), and/or mixed reality (MR) direct retinal projector system that may include an AR headset (e.g., a helmet, goggles, or glasses) that uses a reflective holographic combiner to direct light from a light engine into the user's eye, while also transmitting light from the user's environment to thus provide an augmented view of reality.
The holographic combiner may be recorded with a series of point-to-point holograms; one projection point interacts with multiple holograms to project light onto multiple eye box points. The holograms may be arranged so that neighboring eye box points are illuminated from different projection points.
The holographic combiner and light engine may be arranged to separately project light fields with different fields of view and resolution that optimize performance, system complexity and efficiency, so as to match the visual acuity of the eye.
The light engine may implement foveal projectors that generally project wider diameter beams over a smaller central field of view, and peripheral projectors that generally project smaller diameter beams over a wider field of view.
The light engine may include multiple independent light sources (e.g., laser diodes, LEDs, etc.) that can independently project from the different projection points, with a proportion being foveal projectors and a proportion being peripheral projectors.
In some embodiments, the light engine may include two or more two-axis scanning mirrors to scan the light sources; the light sources are appropriately modulated to generate the desired image.
The light engine may include a series of optical waveguides with holographic or diffractive gratings that move the light from the light sources to generate beams at the appropriate angles and positions to illuminate the scanning mirrors; the light is then directed into additional optical waveguides with holographic film layers recorded with diffraction gratings to expand the projector aperture and to maneuver the light to the projection positions required by the holographic combiner.
In some embodiments, the light engine may include at least one focusing element (e.g., optical lens, holographic lens, etc.) for each projector to focus emitted light beams such that, once reflected off the holographic combiner, the light is substantially collimated when it enters the subject's eye. The required focal surface may be complicated by the astigmatism of the holographic combiner, but is a curved surface in front of the combiner. The ideal focal surface is different for different eye box positions, and errors may lead to less collimated output.
Apple's patent FIG. 5 below illustrates an augmented reality (AR) system that uses a reflective holographic combiner to direct light from a light engine into a subject's eye, while also transmitting light from the environment to the subject's eye.
Apple's patent FIG. 7 below illustrates high-level components of an AR system.
Apple's patent FIG. 8 below illustrates foveal and peripheral projectors of a light engine in an AR headset; FIG. 9 illustrates light beams from foveal projectors in an AR system.
Apple's patent FIG. 27 below illustrates a best fit focus curve and a focusing element for foveal projections in an AR system.
For tech enthusiasts, developers and engineers that want more details, check out granted patent 11,215,829.
Richard J. Topliss: Senior Camera Technology Specialist
Richard Tsai: Sr. Camera Design Engineer
Alexander Shpunt: Distinguished Engineer. Was the CTO & Founder of PrimeSense that Apple acquired in 2013.
Paul Gelsinger: Optical Engineer
Gregory Thomas: Senior Area Manager
The Remaining Patents Granted to Apple Today