Methods of recording a volume Bragg grating are provided. A recording medium is formed from a matrix polymer precursor, an inimer comprising a polymerizable functional group and a controlled radical reactive group, a first photoinitiator system that is more reactive with the polymerizable functional group than the controlled radical reactive group in the presence of an excitation source, and a photoredox catalyst. The medium is cured thereby forming a support matrix. The medium is exposed to light causing the first photoinitiator system to react with the polymerizable functional group and to polymerize the inimer within the support matrix thus forming a latent grating image of the volume Bragg grating within the medium. The latent grating image comprises a plurality of bright fringes and a plurality of dark fringes. A concentration of polymerized inimer is higher in the plurality of bright fringes than in the plurality of dark fringes.

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.

A method for large volume holographic imaging is provided that may include determining projection operators within sub-volumes of a decomposed target volume, and determining a point aggregation operator for each sub-volume based on the projection operators. The method may further include receiving holographic field measurement data set captured for the target volume via the sensor array, generating a sub-volume interest value for each sub-volume by applying the holographic field measurement data set to each point aggregation operator, determining a sub-volume with a highest sub-volume interest value, and determining respective lower-tier sub-volume interest values for lower-tier sub-volumes of the sub-volume with the highest sub-volume interest value. The lower-tier sub-volumes may be defined by decomposing the sub-volume with the highest sub-volume interest value. Additionally, the method may include generating an image of the target volume based on the lower-tier sub-volume interest values.

Methods of recording volume Bragg gratings are provided. A recording medium includes matrix polymer precursor, inimer comprising a polymerizable functional group and a controlled radical reactive group, photoinitiator more reactive with the polymerizable functional group than the controlled radical reactive group in the presence of an excitation source, and a photoredux catalyst. The medium is cured to form a support matrix. The medium is exposed to the excitation source, forming a latent grating having bright fringes and dark fringes. Polymerized inimer is more concentrated in the bright fringes than in the dark fringes. A high refractive index monomer reactive with the controlled radical reactive group is diffused into the medium and exposed to light to cause controlled radical polymerization between the high refractive index monomer and the controlled radical reactive group of the polymerized inimer, driving up a refractive index of the bright fringes relative to the dark fringes.

Methods, apparatus, devices, and systems for reconstructing three-dimensional objects with display zero order light suppression are provided. In one aspect, a method includes illuminating a display with light, a portion of the light illuminating display elements of the display, and modulating the display elements of the display with a hologram corresponding to holographic data to diffract the portion of the light to form a holographic scene corresponding to the holographic data, and to suppress display zero order light in the holographic scene. The display zero order light can include reflected light from the display.

Methods, apparatus, devices, and systems for reconstructing three-dimensional objects with display zero order light suppression are provided. In one aspect, a method includes illuminating a display with light at an incident angle, a portion of the light illuminating display elements of the display, modulating the display elements of the display with a hologram corresponding to holographic data to diffract the portion of the light to form a holographic scene corresponding to the holographic data, and redirecting display zero order light away from the holographic scene to suppress the display zero order light in the holographic scene. The display zero order light includes reflected light from the display.

Methods, apparatus, devices, and systems for reconstructing three-dimensional objects with display zero order light suppression are provided. In one aspect, a method includes illuminating a display with light at an incident angle, a portion of the light illuminating display elements of the display, modulating the display elements of the display with a hologram corresponding to holographic data to diffract the portion of the light to form a holographic scene corresponding to the holographic data, and redirecting display zero order light away from the holographic scene to suppress the display zero order light in the holographic scene. The display zero order light includes reflected light from the display. The light includes a plurality of different colors of light.

The invention relates to a security element (1) with a first volume hologram layer (11), which spans a coordinate system with the coordinate axes x and y (3, 4) perpendicular to each other in an unbent state of the security element (1), wherein a first volume hologram is introduced into the first volume hologram layer (11) in at least one first area (51), wherein the first volume hologram is formed such that a first item of information (21-30) is visible for an observer (7) in a first observation situation in a first predefined bent state of the security element (1) and is not visible in the first observation situation in the unbent state of the security element (1) or vice versa.

Holographic energy directing systems may include a waveguide array and a relay element. Disclosed calibration approaches allows for mapping of energy locations and mapping of energy locations to angular direction of energy as defined in a four-dimensional plenoptic system. Distortions due to the waveguide array and relay element may also be compensated.

A functionalized waveguide for a detector system is provided. A transparent base body of the waveguide has a partly transparent coupling-in region and a coupling-out region at a distance therefrom in a first direction. The coupling-in region includes at least two volume holograms, which each deflect only part of radiation coming from an object to be detected and striking the front side such that the deflected part, as coupled-in radiation in the base body, is propagated by reflections as far as the coupling-out region and strikes the coupling-out region. The volume holograms of the coupling-in region differ in that their deflection function has different spectral angular properties. The coupling-out region deflects at least part of the coupled-in radiation striking said region such that the deflected part exits the base body via the front side or rear side, in order to strike the detector system.