G03H2001/0439

METHOD AND APPARATUS FOR HOLOGRAPHIC RECORDING

The present invention relates to a method and apparatus for holographic recording based on holographic printing technology, and more specifically, to a method and apparatus for holographic recording, in which the hologram is recorded after the deviation in diffraction efficiency for each hogel is pre-compensated for by varying the intensity (luminance) of the object beam for each hogel during the hologram recording in response to a deviation in diffraction efficiency (reconstruction efficiency) for each hogel of a holographic recording surface that occurs when the hologram is reproduced. Accordingly, the reproduction imbalance of a near-eye display (NED) using a holographic optical element (HOE) is resolved by controlling the diffraction efficiency uniform on the entire holographic recording surface when the hologram is reproduced.

Photopolymer composition

The present disclosure relates to a photopolymer composition, and more particularly, to a compound having a novel structure, a photopolymer composition including the compound as a dye, a hologram recording medium produced from the photopolymer composition, an optical element including the hologram recording medium, and a holographic recording method using the photopolymer composition.

STRUCTURE AND MANUFACTURING METHOD OF HOLOGRAPHIC OPTICAL ELEMENTS

Manufacturing methods are disclosed to produce a seamless hologram using a free-form-lens enabling arbitrary adjustment of diffraction angle and also a thick hologram made of transparent inorganic materials and heat and UV resistant is disclosed.

System and method for autostereoscopic imaging using holographic optical element

Systems and methods for creating an autostereoscopic display include a holographic optical element (HOE) recorded using coherent light divided into diverging reference and object beams that illuminate the HOE from opposite sides. The object beam passes through first and second diffusers with one diffuser being a directional diffuser to more uniformly illuminate the HOE. Optic elements may be used to more closely match beam diameters and/or profiles of the recording wavelengths. Baffles may be positioned on opposite sides of the HOE with openings aligned proximate the reference beam and object beam paths, respectively, to reduce stray reflections and provide ambient air flow attenuation or damping. One or more edges of the HOE are masked to reduce or prevent stray light from entering and reflecting within the HOE during recording.

FILTER FOR LASER PROTECTION
20190129077 · 2019-05-02 ·

A method of forming a filter, comprising the steps of:selecting at least a first wavelength corresponding to a predetermined laser threat and having a first colour in the visible spectrum;providing a generally transparent substrate and forming a first notch filter region therein configured to substantially block incident radiation thereon of wavelengths within a first predetermined wavelength band including said first wavelength;selecting a second wavelength having a second colour in the visible spectrum and forming a colour balancing notch filter region in said substrate configured to block incident radiation thereon of wavelengths within a wavelength band including said second wavelength, thereby to balance or neutralise any colour distortion of said substrate caused by said first notch filter region.

SKEW MIRRORS, METHODS OF USE, AND METHODS OF MANUFACTURE

An optical reflective device referred to as a skew mirror, having a reflective axis that need not be constrained to surface normal, is described. Examples of skew mirrors are configured to reflect light about a constant reflective axis across a relatively wide range of wavelengths. In some examples, a skew mirror has a constant reflective axis across a relatively wide range of angles of incidence. Exemplary methods for making and using skew mirrors are also disclosed. Skew mirrors include a grating structure, which in some examples comprises a hologram.

Holographic substrate-guided wave-based see-through display

A holographic substrate-guided wave-based see-through display has a microdisplay, capable of emitting light in the form of an image. The microdisplay directs its output to a holographic optical element, capable of accepting the image from the microdisplay, and capable of transmitting the light. The holographic optical element couples its output to an elongate substrate, capable of accepting the light from the holographic optical element at a first location, and transmitting the light along a length of the substrate by internal reflection to a second location, the elongate substrate being capable of transmitting the accepted light from the second location. The substrate couples out what it receives to a transparent holographic optical element, capable of accepting the light transmitted from the substrate and transmitting it to a location outside of the holographic optical element as a viewable image.

FILTER FOR LASER PROTECTION
20190107656 · 2019-04-11 ·

A method of forming a conformable filter, comprising the steps of: selecting at least a first wavelength corresponding to a predetermined laser threat; providing a conformable photosensitive film (320) and exposing said film to radiation from a focused laser source (100) of said first wavelength to create a first filter region therein configured to substantially block incident radiation thereon substantially only of said first wavelength while substantially allowing other visible wavelengths to be transmitted; selecting a bandwidth corresponding to a first predetermined wavelength band including said first wavelength and exposing said polymeric film (320) to radiation from one or more further laser sources of respective different wavelengths within said first predetermined wavelength band to create a notch filter region therein, including said first filter region, said notch filter region being configured to substantially block incident radiation thereon at a wavelength within said first predetermined wavelength band whilst substantially allowing visible wavelengths outside of said first predetermined wavelength band to be transmitted therethrough.

PUPIL EQUALIZATION
20190101760 · 2019-04-04 ·

An optical reflective device for pupil equalization including at least one or more grating structures within a grating medium is disclosed. The grating structures may have reflective axes that need not be constrained to surface normal. The grating structures are configured to reflect light about substantially constant reflective axes across a relatively wide range of wavelengths. The optical reflective device may reflect light towards a specific location, such as an exit pupil or eye box. Each grating structure within the device may be configured to reflect light of a particular wavelength at a plurality of incidence angles.

VARIABLE SHEAR WITH VOLUME HOLOGRAMS

An optical device including a first rigid substrate, a flexible holographic optical element, a transparent flexible material having a variable shear transmission property across an in-plane direction of the flexible holographic optical element, and a second rigid substrate, wherein the flexible holographic optical element and the transparent flexible material are located between the first and second rigid substrates, wherein the variable shear transmission property of the transparent flexible material transmits variable amounts of a shear force applied to the first or second rigid substrates across the in-plane direction of the flexible holographic optical element.