Systems, devices, and methods for holographic optical elements are described. A holographic optical element includes a first layer of holographic material and a second layer of holographic material. The first layer of holographic material includes a first hologram responsive to light in a first waveband and a second hologram responsive to light in a second waveband. The second layer of holographic material includes a third hologram responsive to light in a third waveband and may include a fourth hologram responsive to light in a fourth waveband. The first, second, third, and fourth wavebands are distinct and may comprise light of red, blue, green, and infrared wavelengths, respectively. Distribution of the three or four holograms on two layers of holographic material allows each hologram to have an index modulation of greater than 0.016, a diffraction efficiency of greater than 15%, and an angular bandwidth of greater than 12.

Systems, devices, and methods for holographic optical elements are described. A holographic optical element includes a first layer of holographic material and a second layer of holographic material. The first layer of holographic material includes a first hologram responsive to light in a first waveband and a second hologram responsive to light in a second waveband. The second layer of holographic material includes a third hologram responsive to light in a third waveband and may include a fourth hologram responsive to light in a fourth waveband. The first, second, third, and fourth wavebands are distinct and may comprise light of red, blue, green, and infrared wavelengths, respectively. Distribution of the three or four holograms on two layers of holographic material allows each hologram to have an index modulation of greater than 0.016, a diffraction efficiency of greater than 15%, and an angular bandwidth of greater than 12.

Systems, devices, and methods for holographic optical elements are described. A holographic optical element includes a first layer of holographic material and a second layer of holographic material. The first layer of holographic material includes a first hologram responsive to light in a first waveband and a second hologram responsive to light in a second waveband. The second layer of holographic material includes a third hologram responsive to light in a third waveband and may include a fourth hologram responsive to light in a fourth waveband. The first, second, third, and fourth wavebands are distinct and may comprise light of red, blue, green, and infrared wavelengths, respectively. Distribution of the three or four holograms on two layers of holographic material allows each hologram to have an index modulation of greater than 0.016, a diffraction efficiency of greater than 15%, and an angular bandwidth of greater than 12.

The invention relates to a method for producing a holographic optical element by providing a recording stack comprising at least one recording element laminated on at least one supporting element, irradiating at least a part of the recording stack with at least one recording beam in an irradiating step, wherein during the irradiating step, the recording stack bends, providing a bending deviation threshold for the recording stack, and adjusting at least one first process parameter such that an expected maximum bending deviation of the recording stack does not exceed the bending deviation threshold, wherein the at least one first process parameter influences the bending behavior of the recording stack during the irradiating step.

A main object of the present disclosure is to provide a hologram structure having excellent forgery preventability and designability. The present disclosure achieves the object by providing a hologram structure comprising: a hologram layer including a reflection type hologram forming region carrying a recorded phase type Fourier transform hologram that transforms an incident light from a point light source into a desired optical image; and a vapor deposition layer formed so as to come into contact with a concavo-convex surface of the reflection type hologram forming region of the hologram layer, and a size of the reflection type hologram forming region in plan view is in a range of 5 mm square or more and 50 mm square or less.

The present invention provides a means for suppressing an occurrence of a ghost by enhancing diffraction efficiency of a holographic optical element having a volume hologram recording layer. The present invention is a holographic optical element including: a volume hologram recording layer containing a photopolymer, and at least one adjacent layer which is in contact with the volume hologram recording layer and contains a resin, wherein a diffraction grating is formed so as to extend from the volume hologram recording layer to the adjacent layer.

Lighting information comprising at least the reflectance data of a plurality of regions of an object surface is generated and printed out as a series of relightable holograms. Each of the printed holograms comprises the reflectance data of a corresponding region of the object. A model of the object is generated such that the model also comprises a plurality of portions corresponding to the regions of the object surface. The series of holograms are each affixed to a portion of the model such that a particular hologram of the series which encodes the reflectance data of a particular region of the object is affixed to the corresponding portion of the model. In an embodiment, the model of the object is generated from a metal. The series of holograms is engraved directly onto the metallic model such that a particular hologram of the series which encodes the reflectance data of a particular region of the object is engraved onto the corresponding portion of the metallic model.

A hologram recording composition includes at least: a photopolymerizable compound containing at least a first photopolymerizable monomer; binder resin that is inactive to photopolymerization; and a photopolymerization initiator. A change in polarity of the first photopolymerizable monomer by photopolymerization reduces compatibility with the binder resin of the photopolymerizable compound than that before polymerization, the compatibility of the photopolymerizable compound before the polymerization being high.

Disclosed herein is a lens for a wearable projection system. The lens includes a holographic optical element embedded within the lens and covering a portion of the viewable area of the lens. The lens can be manufactured by providing a first lens blank, affixing the HOE to a portion of the first lens blank, and forming a second lens blank on the first lens blank to embed the HOE between the lens blanks.

Disclosed herein is a lens for a wearable projection system. The lens includes a holographic optical element embedded within the lens and covering a portion of the viewable area of the lens. The lens can be manufactured by filling a cavity in a lens blank with a photosensitive material and exposing the photosensitive material to a number of light beams to form the HOE.