Reald Inc.

Colorlink, Inc.

University of Colorado

Meta Platforms Technologies, LLC

Gary Sharp Innovations, LLC

Facebook Technologies, LLC

Magic Leap, Inc.

University Technology Corporation

Reald Spark, LLC

Other

United States of America As Represented by the Secretary of the Air Force

Wavefront Technology, Inc.

Boulder Nonlinear Systems, Inc.

Reald Luxe, LLC

Reaid Inc.

Gary Dean Sharp

Michael Geraint Robinson

David A Coleman

Kristina M Johnson

Miller H Schuck

Jianmin Chen

Anthony D McGettigan

Kevin R Curtis

Douglas J McKnight

Jonathan R Birge

Joel Mikael Petersen

Graham John Woodgate

Jonathan Harrold

Christopher Chapman Rich

Raymond Jacob Lewandowski

Chulwoo Oh

Ravi Kumar Komanduri

Scott Gilman

Jian-Yu Liu

Steven A Serati

Terry Norton

Jay E Stockley

Jacques Gollier

Jack P Salerno

Paul Francis McManamon

Bradley William Walker

Miller Harry Schuck, Iii

Mark O Freeman

Warren D Slafer

Chris Rich

Anat Sneh

Michael S Salisbury

Ray Lewandowski

Charles S Wong

Darlene K Kondo

Teresa Kaye Ewing

A switchable optical assembly comprises a switchable waveplate configured to be electrically activated and deactivated to selectively alter the polarization state of light incident on the switchable waveplate. The switchable waveplate comprises first and second surfaces and a liquid crystal layer disposed between the first and second surfaces. The liquid crystal layer comprises a plurality of liquid crystal molecules. The first surface and/or the second surface may be planar. The first surface and/or the second surface may be curved. The plurality of liquid crystal molecules may vary in tilt with respect to the first and second surfaces with outward radial distance from an axis through the first and second surfaces and the liquid crystal layer in a plurality of radial directions. The switchable waveplate can include a plurality of electrodes to apply an electrical signal across the liquid crystal layer.

Wide field-of-view polarization switches with liquid crystal optical elements with pretilt

A reflective polarization rotator based on a twisted nematic (TN) liquid crystal (LC) configuration may be optimized for achromatic performance in both bright and dark states by compensating wavelength dependence of polarization transformation by the TN LC layer. At linear achromatic input polarization, the compensation aims to provide a circular achromatic polarization at the reflector, which guarantees the achromaticity of the 90 degrees polarization rotation on double pass. The compensation takes care to preserve linear polarization at the reflector when the LC device is driven to a vertical LC director configuration. Such an approach ensures that the performance of the polarization rotator is achromatic in both driven and undriven states of the LC device.

Broadband polarization rotator and optical switch

A switchable optical assembly comprises a switchable waveplate configured to be electrically activated and deactivated to selectively alter the polarization state of light incident thereon. The switchable waveplate comprises first and second surfaces and a liquid crystal layer disposed between the first and second surfaces. The first liquid crystal layer comprises a plurality of liquid crystal molecules. Said first and second surfaces may be curved. Said plurality of liquid crystal molecules may vary in tilt with respect to said first and second surfaces with outward radial distance from an axis through said first and second surfaces and said liquid crystal layer in a plurality of radial directions. The switchable waveplate additionally comprises a first plurality of electrodes to apply an electrical signal across said first liquid crystal layer.

Optical systems that can produce digitally switchable optical power, optical pathlength, or both. It can apply to reconfigurable wide-angle optical systems that are compact, light-weight, and light-efficient. Architectures that increase pathlength can utilize polarization splitters to produce an additional round-trip of one or more optical cavities. Changing the focus distance of synthetic imagery in augmented/virtual reality systems is an example of an application where the techniques taught herein are particularly well suited. Passive double-cavity systems can be used to increase the throughput and decrease the stray-light/ghosts in polarization-based compact wide-angle lenses.

Compact polarization-based multi-pass optical architectures

An eyewear lens is described that provides polarization filtering and spectral filtering using polarization interference. The lens produces enhanced saturation and colorfulness, increasing enjoyment when observing commonly encountered imagery. The lens can be configured to optimize accuracy/efficiency when performing a task involving colored imagery, and can improve performance in sports. The lens can further be helpful for color discrimination by those with certain types of color vision deficiency.

Optical filter with color enhancement

An imaging system that contains a display, a polarization folded path lens with an intended image signal path and an exit pupil wherein light entering the PFP lens from the display substantially follows the intended signal path. A variant of this system is disclosed where the light entering the PFP lens substantially follows the signal path and leaves via the Exit pupil (as opposed to being aperture). Compared to the prior art, the techniques described herein improve transmission efficiency and reduce corruption of the image by non-signal path light.

Polarization folded path device with complementary angle filtering

Polarization-based optical angle-filters disclosed herein can be engineered to transmit a prescribed amount of light as a function of incidence angle and azimuth. Such filters can transmit light without introducing artifacts, making them suitable for the image-path of an optical system. One example may include an angle-filter having an input circular polarizer, an analyzing circular polarizer, and a retarder positioned between the circular polarizers, the retarder having a thickness-direction retardation. The thickness-direction retardation of the retarder (R) is selected to produce a prescribed angle-of-incidence dependent transmission function, and the circular polarizers reduce the amount of azimuth-dependence in the transmission function.

Polarization-based filters with angle-sensitive transmission having circular polarizers

A compound retarder that creates independent control of Rand R. This can be done by forming a three-layer compound retarder, including a pair of matched &#x2212;A-plates, combined with single +A-plate. The +A-plate is typically an MD-stretched film, with retardation that is specific to the in-plane requirements (R) of the application. The pair of &#x2212;A-plates have their optic axes crossed, such that R=0, with an optic axis aligned parallel to the +A-plate. A single retardation value for the &#x2212;A-plate can produce improved field-of-view performance over a broad range of Rvalues, making it a very practical means of universal compensation. While Ris typically associated with a single retarder, retarder stacks with a diverse range of optic-axis orientations can be considered to have a compound (or composite) Rvalue (R). The three-layer compound retarder has the practical benefit of enabling field-of-view compensation across a broad range of normal-incidence polarization transformations.

Wide-angle compensation of uniaxial retarder stacks

A laminator for high-precision solvent-bonding of retardation films is disclosed. The laminator is capable of producing laminates with high orientation repeatability and low in-plane stress which can otherwise create gaps between optimum theoretical performance and that which is physically realizable. Batch-mode laminators are scalable to large area mother-sheets and are suited to high-throughput manufacturing.

Equipment and processes for precision fabrication of solvent-laminated retarder-stacks

In polarization-based optical systems, preserving a state-of-polarization (SOP) over a prescribed range of incidence angles and wavelengths may be necessary. Optical materials with local normal tilted with respect to an incident ray can introduce an undesirable polarization nonuniformity that can be substantially corrected using a compensator as disclosed herein. The compensator may include a uniaxial retarder and a z-partial polarizer (ZPP). The ZPP may include a uniaxial material with an absorption axis normal to the substrate.

Polarization compensator for tilted surfaces

A three (or more) polarizer arrangement is used to demonstrate a wide-angle variable-neutral-density (VND) filter that has both contrast uniformity and color uniformity. According to one embodiment, the outer polarizers effectively counter-rotate with respect to a fixed center polarizer as a means of compensating for transmission non-uniformity associated with geometrical polarization distortions experienced by off-normal rays. In particular, the achromatic compensation arrangement enables angle uniformity relative to normal-incidence transmission when the number of stops of attenuation grows large (e.g. 10-stops, or OD3). The filters are useful for cameras or instrumentation allowing mechanical or electromechanical tuning.

Wide angle variable neutral density filter

A device for manipulating the polarization of light which includes a first retarder-stack (Stack) that converts the polarization of input light from a first polarization basis vector (PBV) to a second polarization basis vector (PBV), a second retarder-stack (Stack) that returns the polarization of light from PBVto PBV, and one or more optically functional layers between Stackand Stack. Stackhas a plurality of layers, wherein the number of layers, retardation values, and orientations of layers in Stackare selected to produce a PBVthat is substantially spectrally-uniform over a prescribed range of wavelengths. PBVis a non-trivial eigen-polarization of combined Stackand Stack. Stackhas a plurality of layers and Stackis arranged in series with Stack. Alternatively, instead of two different stacks, a reflector may be used to produce a return pass through Stack

Retarder stack pairs for polarization basis vector transformations

Hollow optical elements that derive optical power from compound-curved reflective surfaces to produce a desired composite optical power. The reflective surfaces in combination with polarization control, can produce a triple-pass arrangement that determines the optical power. Two functional films, one or both of which are formed (e.g., thermoformed), can be joined at the perimeter to form units that are mechanically robust and therefore preserve optical performance under mechanical load. The air-spaced cavity formed between the two layers is free of birefringence concerns, where polarization control is crucial to contrast. These optical elements can be installed in frames or headsets to form lightweight wearable magnifiers, wide-angle collimators, tele-photo lenses, or for any application requiring optical power. They may be most appropriate for applications where light efficiency is not critical, such as well-lit environments, where the insertion-loss of 1 to 2 stops is not problematic.

Hollow triple-pass optical elements

Growing community of inventors

Boulder, CO, United States of America

Gary Dean Sharp