A method for determining the validity of a parallax image, including: receiving a parallax image's captured two-dimensional image having at least three target identifiers, where at least two target identifiers are located at different depth planes in the parallax image; identifying at least three target identifiers in the parallax image's captured two-dimensional image and determining spatial relationship between at least three target identifiers in the two-dimensional image of the parallax image; comparing the spatial relationship of at least three target identifiers in the parallax image's captured two-dimensional image against a predetermined spatial relationship of at least three target identifiers that indicates authenticity; and adjudicating the authenticity of the parallax image based on the degree of difference between spatial relationship of at least three target identifiers in the parallax image's captured two-dimensional image and the predetermined spatial relationship of at least three target identifiers.

A carrier medium embodied as a light guide has an input coupling region and an output coupling region, each of which are embodied as a holographic element. The carrier medium forms a cover plate for an image display region of a screen and the input coupling region is at least one partial region of the cover plate surface. Light incident on the input coupling region from the surroundings is coupled into the carrier medium, transmitted to the output coupling region by internal reflection and is in turn coupled out from the output coupling region. The coupled-out light is captured by an image capturing device and used to generate image data correlated with the captured light.

An all-optical Diffractive Deep Neural Network (D.sup.2NN) architecture learns to implement various functions or tasks after deep learning-based design of the passive diffractive or reflective substrate layers that work collectively to perform the desired function or task. This architecture was successfully confirmed experimentally by creating 3D-printed D.sup.2NNs that learned to implement handwritten classifications and lens function at the terahertz spectrum. This all-optical deep learning framework can perform, at the speed of light, various complex functions and tasks that computer-based neural networks can implement, and will find applications in all-optical image analysis, feature detection and object classification, also enabling new camera designs and optical components that can learn to perform unique tasks using D.sup.2NNs. In alternative embodiments, the all-optical D.sup.2NN is used as a front-end in conjunction with a trained, digital neural network back-end.

Improvements to gratings for use in waveguides and methods of producing them are described herein. Deep surface relief gratings (SRGs) may offer many advantages over conventional SRGs, an important one being a higher S-diffraction efficiency. In one embodiment, deep SRGs can be implemented as polymer surface relief gratings or evacuated periodic structures (EPSs). EPSs can be formed by first recording a holographic polymer dispersed liquid crystal (HPDLC) periodic structure. Removing the liquid crystal from the cured periodic structure provides a polymer surface relief grating. Polymer surface relief gratings have many applications including for use in waveguide-based displays.

Improvements to gratings for use in waveguides and methods of producing them are described herein. Deep surface relief gratings (SRGs) may offer many advantages over conventional SRGs, an important one being a higher S-diffraction efficiency. In one embodiment, deep SRGs can be implemented as polymer surface relief gratings or evacuated periodic structures (EPSs). EPSs can be formed by first recording a holographic polymer dispersed liquid crystal (HPDLC) periodic structure. Removing the liquid crystal from the cured periodic structure provides a polymer surface relief grating. Polymer surface relief gratings have many applications including for use in waveguide-based displays.

A display body includes a base material having a first region, a second region, and a third region. In the display body, the first region is formed with a code or an image of identification information, and the second region is formed with a hidden code containing information obtained by encoding at least a part of the identification information. An encrypted ciphertext is recorded in the third region, and the ciphertext is generated from at least one of the code of the identification information and the hidden code.

The present invention relates to surface functionalized titanium dioxide nanoparticles, a method for its production, a coating composition, comprising the surface functionalized titanium dioxide nanoparticles and the use of the coating composition for coating holo-grams, wave guides and solar panels. Holograms are bright and visible from any angle, when printed with the coating composition, comprising the surface functionalized tita-nium dioxide nanoparticles.

Embodiments herein describe a sub-micron 3D diffractive optics element and a method for forming the sub-micron 3D diffractive optics element. In a first embodiment, a method is provided for forming a sub-micron 3D diffractive optics element on a film stack disposed on a substrate without planarization. The method includes forming a hardmask on a top surface of a film stack. Forming a mask material on a portion of the top surface and a portion of the hardmask. Etching the top surface. Trimming the mask. Etching the top surface again. Trimming the mask a second time. Etching the top surface yet again and then stripping the mask material.

The present disclosure relates to a hologram medium comprising: a polymer substrate including a polymer resin in which a silane-based functional group is located in a main chain or a branched chain, wherein a fine pattern is formed on at least one surface of the polymer substrate, and an optical element.

A method is provided. The method includes directing a first beam to a polarization sensitive recording medium. The method also includes directing a second beam to the polarization sensitive recording medium to interfere with the first beam to generate a polarization interference pattern, to which the polarization sensitive recording medium is exposed. One of the first beam and the second beam has a planar wavefront and the other has a non-planar wavefront. A first propagation direction of the first beam and a second propagation of the second beam are non-parallel.