Adaptive lens assemblies including polarization-selective lens stacks for augmented reality display

Inventors

KOMANDURI, Ravi Kumar • Oh, Chulwoo

Assignees

Magic Leap Inc

Abstract

The present disclosure relates to display systems and, more particularly, to augmented reality display systems an related methods. In one aspect, an adaptive lens assembly includes a lens stack configured to exert polarization-dependent optical power to linearly polarized light. The lens stack includes a birefringent lens and an isotropic lens contacting each other to form a conformal interface therebetween. The adaptive lens assembly is configured to be selectively switched between a plurality of states having different optical powers.

Core Innovation

An augmented reality display system uses an adaptive lens assembly of a head mounted augmented reality display device to focus virtual images at a plurality of depth planes among a real world view. The focusing uses selectively switching the adaptive lens assembly between a plurality of states having different optical powers so that the virtual images are focused at plane depths among the real world view while simultaneously refocusing the real world view to appear without substantial distortion.

The adaptive lens assembly includes a lens stack supported by the head mounted augmented reality display device. The lens stack comprises a birefringent lens and an isotropic lens contacting each other to form a conformal interface between the contacting surfaces, and the adaptive lens assembly is configured to exert polarization-dependent optical power to linearly polarized light.

Switching among the plurality of optical-power states is implemented using polarization control and electrically controlled switching elements, including switchable TN liquid-crystal switchable half-waveplates and/or lens-stack configurations using reactive mesogens with electrodes, to create switchable polarization-dependent optical power. In integrated AR operation, the system includes a waveguide assembly that guides and outcouples light through an output surface to the adaptive lens assembly, and polarization management embodiments include polarizing reflectors and reflector stacks, including cholesteric liquid crystal polarizing notch reflectors and related reflector and optical components such as quarter-waveplates.

Claims Coverage

The provided material includes four independent method claims for AR focusing that share a common inventive structure: focusing virtual images at multiple depth planes using an adaptive lens assembly with polarization-dependent optical power formed by a birefringent lens contacting an isotropic lens via a conformal interface, and selectively switching among a plurality of optical-power states to focus the virtual images while simultaneously refocusing the real world view to appear without substantial distortion. Additional inventive coverage is provided for waveguide guiding and outcoupling, polarization-management reflectors, and multi-side adaptive lens implementations.

Across the independent claims, the inventive core is the use of a polarization-dependent adaptive lens assembly in an AR head-mounted display, including a lens stack with a birefringent lens contacting an isotropic lens via a conformal interface, and selective switching among multiple optical-power states to focus virtual images at multiple depth planes while refocusing the real world without substantial distortion. Claim coverage further includes waveguide guiding and outcoupling and distinct polarization-management reflector configurations, including polarizing reflectors passing one polarization and reflecting another, including cholesteric liquid crystal implementations for circular polarization.

Stated Advantages

Documented Applications