Patent classifications
G02B5/1833
OPTICAL COMBINER WITH UNIFORM ILLUMINANCE THROUGHPUT
A device includes a display configured to generate an image light. The device also includes a waveguide optically coupled with the display and configured to guide the image light to an exit pupil of the device. The waveguide includes a grating including a birefringent material, and a birefringence of the grating is configured to increase along a pupil-expanding direction of the device.
THIN LIQUID CRYSTAL STACK FOR POLARIZATION CONVERSION
A polarization conversion device includes a geometric phase grating and an angular selective waveplate. The geometric phase grating includes a first liquid crystal layer and is configured to diffract a unpolarized or partially polarized incident light beam into a first light beam and a second light beam (e.g., in two different diffraction orders). The first light beam is characterized by a first polarization state and propagates in a first direction. The second light beam is characterized by a second polarization state and propagates in a second direction. The angular selective waveplate includes a second liquid crystal layer, and functions as a zero or full-wave plate for the first light beam incident in the first direction and a half-wave plate for the second light beam incident in the second direction.
HIGH EFFICIENCY INFRARED REFLECTOR HAVING REDUCED COLOR
Infrared reflectors are described. In particular, infrared reflectors with reduced off-axis color are described. Such infrared reflectors may be useful in laminated glass constructions, particularly for applications where the glass may be exposed to water.
SYSTEM AND METHOD FOR FABRICATING LIQUID CRYSTAL POLARIZATION HOLOGRAMS
A system includes a light outputting element configured to output a first beam propagating toward a beam interference zone from a first side of the beam interference zone. The system also includes a reflective assembly configured to reflect the first beam back as a second beam propagating toward the beam interference zone from a second side of the beam interference zone. The first beam and the second beam interfere with one another within the beam interference zone to generate a polarization interference pattern.
PHASE STRUCTURE ON SURFACE-RELIEF GRATING-BASED WAVEGUIDE DISPLAY
A waveguide display includes a substrate transparent to visible light, a first grating on the substrate and configured to couple display light into or out of the substrate, and a phase structure on the substrate and configured to change a polarization state of the display light after or before the display light reaches the first grating. The first grating is characterized by a polarization-dependent diffraction efficiency. The first grating includes, for example, a surface-relief grating or a volume Bragg grating.
Segmented birefringent chromatic beam shaping device
A segmented birefringent chromatic beam shaping device comprises at least three birefringent chromatic segments arranged side by side in a pupil of the beam shaping device. The birefringent chromatic segments are essentially nλ waveplates at a first design wavelength. At a second design wavelength, the birefringent chromatic segments are essentially (m+1/2)λ waveplates. Each of the birefringent chromatic segments comprises a stack of birefringent elements including at least three chromatic birefringent elements. Orientations of fast axes of each pair of directly consecutive chromatic birefringent elements of each of the birefringent chromatic segments differ by at least 5 deg. The at least three birefringent chromatic segments comprise same sequences of materials, thicknesses and orientations of their birefringent elements so that they only differ is their orientations in the pupil.
CHOLESTERIC LIQUID CRYSTAL LAYER, METHOD OF FORMING CHOLESTERIC LIQUID CRYSTAL LAYER, LAMINATE, LIGHT GUIDE ELEMENT, AND IMAGE DISPLAY DEVICE
Provided are a cholesteric liquid crystal layer having a high diffraction efficiency, a method of forming the same, and a laminate, a light guide element, and an image display device that include the cholesteric liquid crystal layer. The cholesteric liquid crystal layer is obtained by immobilizing a cholesteric liquid crystalline phase, in which the cholesteric liquid crystal layer has a liquid crystal alignment pattern in which a direction of an optical axis derived from a liquid crystal compound changes while continuously rotating in at least one in-plane direction, in a cross-section observed with a SEM, bright portions and dark portions are tilted, in a case where a tilt angle of a direction in which an in-plane retardation is minimum with respect to a normal line in a slow axis plane or a fast axis plane is represented by θ2, an absolute value of an optical axis tilt angle φ represented by “sin θ2=n.Math.sin φ (n represents an average refractive index of the cholesteric liquid crystal layer)” is 5° or more.
Optical element
The optical element is an optical element comprising a first optically anisotropic layer which is a cured layer of a liquid crystal composition containing a first disk-like liquid crystal compound, in which the optical element has a liquid crystal alignment pattern in which an optical axis of the first disk-like liquid crystal compound is parallel to a surface of the first optically anisotropic layer, the first optically anisotropic layer is disposed along at least one direction in a plane of the first optically anisotropic layer, and orientation of the optical axis of the first disk-like liquid crystal compound rotationally changes continuously, and the orientation of the optical axis rotates by 180° with a period of 0.5 μm to 5 μm.
DEVICE INCLUDING DIFFRACTIVE OPTICAL ELEMENT
A device includes a waveguide, an in-coupling element, and an out-coupling element coupled with the waveguide. The waveguide, the in-coupling element, and the out-coupling element are configured to deliver a plurality of portions of an image light to an eye-box of the device. At least one of the in-coupling element or the out-coupling element includes a polarization selective diffractive element. The polarization selective diffractive element includes a grating including a plurality of microstructures defining a plurality of grooves filled with a passive optically anisotropic material having a first effective refractive index along a groove direction of the grooves and a second effective refractive index along an in-plane direction perpendicular to the groove direction. One of the first effective refractive index or the second effective refractive index substantially matches with a refractive index of the microstructures.
Innovative solutions to improve laser damage thresholds of optical structures
Optical structures, including thin film designs and components with topography, are provided that achieve significantly improved laser damage thresholds and/or ultra-low-loss. These advances may be achieved by utilizing a bulk window including a material having a band gap that is at least 5.0 eV and a thickness. The bulk window can be configured to increase the laser induced damage threshold of the underlying optical structure.