Disclosed are high-density energy directing devices and systems thereof for two-dimensional, stereoscopic, light field and holographic head-mounted displays. In general, the head-mounted display system includes one or more energy devices and one or more energy relay elements, each energy relay element having a first surface and a second surface. The first surface is disposed in energy propagation paths of the one or more energy devices and the second surface of each of the one or more energy relay elements is arranged to form a singular seamless energy surface. A separation between edges of any two adjacent second surfaces is less than a minimum perceptible contour as defined by the visual acuity of a human eye having better than 20/40 vision at a distance from the singular seamless energy surface, the distance being greater than the lesser of: half of a height of the singular seamless energy surface, or half of a width of the singular seamless energy surface.

A light projection apparatus is provided comprising: a source of light; a switchable grating on a first substrate; and a diffractive optical element. Light is diffracted at least once by the switchable grating and is diffracted at least once by the DOE.

An optical device includes an optical assembly having a first end and a second end, the optical assembly including a first optical component and a second optical component, the first optical component having at least a first optical surface, a second optical surface, and a third optical surface that are non-parallel to one another. The first optical surface is curved and extends between the first end and the second end. A first polarization selective redirector is located between the first optical component and the second optical component, and a first polarization rotating redirector is disposed at the second end.

A device includes a polarization non-selective partial reflector configured to transmit a first portion of a first light and reflect a second portion of the first light. The device also includes a polarization selective reflector configured to reflect the first portion of the first light received from the polarization non-selective reflector back to the polarization non-selective reflector. The device further includes a path correction device disposed between the polarization non-selective partial reflector and the polarization selective reflector, and configured to forwardly steer the first portion of the first light propagating between the polarization non-selective partial reflector and the polarization selective reflector.

An optical coupler includes a plurality of volume gratings in a substrate. The gratings include an array of fringes extending along length and thickness dimensions of the substrate. A difference between a refractive index of the fringes and a refractive index of the substrate depends on a depth coordinate along the thickness dimension of the substrate. A dependence of the difference on the depth coordinate has a bell-shaped function which suppresses ghost image formation due to optical crosstalk between gratings of neighboring spatial pitches.

The disclosure provides recording materials include fluorene derivatized monomers and polymers for use in volume Bragg gratings, including, but not limited to, volume Bragg gratings for holography applications. Several fluorene structures are disclosed: simply substituted fluorenes, cardo-fluorenes, and spiro-fluorenes. Fluorene derivatized polymers in Bragg gratings applications lead to materials with higher refractive index, low birefringence, and high transparency. Fluorene derivatized monomers/polymers can be used in any volume Bragg gratings materials, including two-stage polymer materials where a matrix is cured in a first step, and then the volume Bragg grating is written by way of a second curing step of a monomer.

A holography sensor system is provided that includes an illuminator, a backscatter array, an array controller, and processing circuitry. The illuminator may be configured to output an illumination signal into a target volume. The backscatter array may comprise a plurality of backscatter elements. The array controller operably coupled to the backscatter elements, and the array controller may be configured to activate selected backscatter elements to enable the selected backscatter elements to transmit a backscatter signal in response to receipt of the illumination signal. The receiver may be configured to receive the backscatter signals from the selected backscatter elements. The processing circuitry may be configured to receive the backscatter data based on the backscatter signals from the receiver, aggregate the backscatter data with other backscatter data to form a holographic field measurement data set, and generate an image of the target volume based on the holographic field measurement data set.

Methods and systems are described that enable manufacturing of holograms with high spatial frequencies and allow composite master holograms to be formed in reflection configurations. An example system for replicating transmission-type holographic elements includes one or more prisms positioned to receive an illumination beam on a first face. A composite master holographic element is positioned in contact with a second face of the one or more prisms to receive the illumination beam after propagation through he one or more prisms. The composite master hologram includes a reference beam component and an object beam component. The replication hologram is positioned in contact with a third face of the one or more prisms to receive, upon illumination of the master HOE by the illumination beam, a holographic exposure comprising first order diffracted illumination from both the reference beam component and object beam component at an exposure region of the copy HOE.

The technology provides a spectroscopy system having a fringe tilted grating that varies a refractive index to diffract light. The diffracting mechanism may be formed by modulating a refractive index to produce fringe planes that are oriented relative to each other through a depth of the grating material The spectroscopy system includes a detector that converts optical signals into electrical signals to render spectral data. The spectroscopy system employs the fringe tilted grating to minimize fictitious Raman peaks that correspond to a fluorescence response signature.

A grating coupler may be fabricated by exposing a photopolymer layer to grating forming light for forming periodic refractive index variations in the photopolymer layer. The photopolymer layer may be exposed to apodization light for reducing an amplitude of the periodic refractive index variations in a spatially-selective manner. The apodization may also be achieved or facilitated by subjecting outer surface(s) of the photopolymer layer to a chemically reactive agent that causes the refractive index contrast to be reduced near the surface(s) of application. The apodized refractive index profile of the gratings facilitates the reduction of optical crosstalk between different gratings of the grating coupler.