This application discloses an in-line system and method for measuring the optical performance of an HOE in motion during a roll-to-roll fabrication process.

This application discloses an automated system for measuring the quality of an HOE using incoherent light and a camera or image screen.

To provide an authentication device and method for a security medium including a reflective volume hologram having a light source disposed on the front surface side of the reflective volume hologram so that light emitted therefrom is incident on the reflective volume hologram, a first observation device disposed in a pre-designed diffraction direction of the reflective volume hologram, and a second observation device disposed in a direction other than the pre-designed diffraction direction of the reflective volume hologram. Light including a pre-designed diffraction wavelength is emitted from the light source to be incident on the reflective volume hologram, and when the light amount observed in the first observation device is larger in the diffraction wavelength than in other wavelengths, and the light amount observed in the second observation device is smaller in the diffraction wavelength than in other wavelengths, it is determined that the reflective volume hologram is genuine.

An apparatus for measuring a spatial resolution of a hologram reconstructed image optically reconstructed on a space is provided. The apparatus for measuring a spatial resolution of a hologram reconstructed image includes: a measuring unit measuring first spatial frequency resolving powers for a horizontal direction of the hologram reconstructed image and second spatial frequency resolving powers for a vertical direction of the hologram reconstructed image at first spatial positions having a predetermined interval in horizontal and vertical directions within a viewing angle range of the hologram reconstructed image; and an evaluating unit evaluating the spatial resolution of the hologram reconstructed image using the first spatial frequency resolving powers and the second spatial frequency resolving powers measured at each of the first spatial positions.

[Problem to be Solved] Conventional devices for reproduction of holograms for appreciative viewing do not have any functionality to gate access to special content by exploiting the characteristics of the hologram. Further, a system that allows users to easily perform judgment of authenticity has been much awaited as, with holograms, although a counterfeit prevention effect can be expected visually, counterfeit imitations of the holograms themselves are already in circulation. [Means to Resolve the Problem] It is made possible to read holographic barcodes with such portable information consoles as smartphones to perform judgment of authenticity. In this process, by controlling from the portable information console side the light sources illuminating the hologram, it is possible to add a strong authenticity judgment function without a major increase in cost and also without building any special infrastructure.

Light reflected from an illuminated object is mixed with a reference beam and sensed at a sensor array of a digital hologram apparatus. Digital hologram data, determined from the sensed light, is dependent upon complex valued reflection coefficients of the object and upon phase perturbations in propagation paths between the object and the sensor array. Reflectance values, which may be dependent upon expected values of the absolute square of the reflection coefficients, and phase perturbations are determined for which a test function is at an extremum, where the test function contains a data fidelity term dependent upon the hologram data from a single hologram, a first regularization term dependent upon the phase perturbations and a second regularization term dependent upon the reflectance values. An image of the object may be formed from the reflectance values and a wavefront of the reflected light may be determined from the phase perturbations.

The present disclosure provides an anticounterfeiting system based on optical technology that verify the authenticity of protected cinema screens. The optical technology includes taggants embedded or attached to the screen and an optical readout system that can interrogate the taggant layer and receive the taggant output. The taggants are capable of reflecting a pattern that unambiguously demonstrates that the screen contains the taggant. The taggants are covert because they are not visible under normal lighting conditions or during cinema operation, but are detected when interrogated by the optical readout system.

A metrology target having a periodic or quasi-periodic structure, which is characterized by a plurality of parameters. At least one of these parameters varies locally monotonically, wherein the maximum size of this variation over a distance of 5 m is less than 10% of the size of the at least one parameter. In addition, the metrology target has at least one used structure and at least one auxiliary structure, wherein the auxiliary structure transitions progressively into the used structure with regard to the locally monotonically varying parameter. Also disclosed are an associated method and associated device for characterizing structured elements configured as wafers, masks or CGHs.

A projector arranged to project an image within a display area on a display plane. The image comprises a light feature. A light sensor is spatially separated from the display plane. In an aligned state, light forming the light feature of the image on the display plane is at least partially disposed around the light sensor. In the aligned state, substantially no light forming the light feature impinges on the light sensor. The aligned state defines a selected alignment between the display area and the display plane (i.e. a selected position of the display area on the display plane).

Provided is an apparatus and method for encoding a hologram and evaluating a holographic image quality for an amplitude-modulated hologram. A hologram encoding method may include acquiring three-dimensional (3D) information of a scene or an object; generating hologram information based on the 3D information; deriving a real number hologram function by extracting a real number part and an imaginary number part from the hologram information; determining an intermediate hologram function based on a sign characteristic of the real number hologram function; and determining encoded hologram information based on the intermediate hologram function.