The holographic Christmas tree is a holographic device. The holographic Christmas tree projects a three-dimensional image of a Christmas tree. The holographic Christmas tree includes a pedestal, a holographic projector, a substrate, and an image. The image is the three-dimensional image of a Christmas tree. The holographic substrate projects the image into the substrate. The pedestal contains the holographic projector.

Typical waveguides rely on total internal reflection between the outer surfaces of substrates, which can make them highly susceptible to beam misalignment caused by nonplanarity of the substrates. In the manufacturing of the glass sheets commonly used for substrates, ripples can occur during the stretching and drawing of glass as it emerges from a furnace. Although glass manufacturers try to minimize ripples using predictions from mathematical models, it is difficult to totally eradicate the problem from the glass manufacturing process. Typically, these beam misalignments manifest themselves as image distortions and non-uniformities in the output illumination from the waveguide. Many embodiments of the invention are directed toward optically efficient, low cost solutions to the problem of controlling output image quality in waveguides manufactured using commercially available substrate glass and to the problem of compensating the image distortions and non-uniformity of curved waveguides.

An optical assembly includes a first flexible membrane and a first optical element coupled with at least a first portion of the first flexible membrane. The optical assembly also includes a substrate having a curved surface. The first optical element is coupled to the curved surface of the substrate with the first flexible membrane. A method for making an optical assembly includes obtaining a first flexible membrane and a first optical element. The method includes coupling the first optical element with at least a first portion of the first flexible membrane and coupling, with the first flexible membrane, the first optical element to a curved surface of a substrate.

A dielectric based metasurface hologram device includes: a substrate layer provided at a lowermost portion of the dielectric based metasurface hologram device; and a dielectric layer forming a geometric metasurface on the substrate layer. The substrate layer includes a plurality of unit cells which are continuous, and the dielectric layer includes a plurality of nano-structures which are disposed with a predetermined distance therebetween. The single nano-structure is disposed on the unit cell, and a hologram image is formed when an incident light from a light source is reflected by the nano-structure so that a phase of the light is controlled.

A method includes obtaining a first optical assembly including a first optical element and a first flexible membrane. The first optical element has a first optical element surface and a second optical element surface that is opposite to the first optical element surface. The first flexible membrane has a first membrane surface and a second membrane surface that is opposite to the first membrane surface. The first optical element is a geometric phase optical element or a polarization volume hologram optical element. The second optical element surface of the first optical element is coupled with at least a first portion of the first membrane surface of the first flexible membrane. The method also includes coupling the first optical element with the first flexible membrane attached thereto to a target substrate. Also disclosed is an optical assembly comprising the first optical element and the first flexible membrane.

The disclosure relates to an optical waveguide for a display device and to a method for producing such an optical waveguide. The optical waveguide has a substrate on which a hologram layer is arranged. A cover layer includes a light-transmissive material that has been subjected to a curing process is arranged on the hologram layer. The substrate can consist of glass. Alternatively, the substrate likewise consists of a light-transmissive material that has been subjected to a curing process.

A near-eye display device and a wearable device having the same. The near-eye display device includes a laser generation module, an optical waveguide element, and a holographic optical element; the laser generation module is configured to emit parallel laser beams; the optical waveguide element has an in-coupler area and an out-coupler area, the optical waveguide element is configured to receive the parallel laser beams and output the parallel laser beams in parallel after one-dimensional pupil expansion or two-dimensional pupil expansion; the holographic optical element has interference fringes and is attached to the out-coupler area, the holographic optical element is configured to receive the parallel laser beams from the optical waveguide element and to reflect or transmit the parallel laser beams by diffraction to output a plurality of converging image light beams.

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 behaviour of the recording stack during the irradiating step.

An optical element of the present disclosure includes a hologram layer, a resin substrate to which the hologram layer is adhered, and a holder portion that supports the resin substrate and has a thermal expansion coefficient smaller than that of the resin substrate. One of the holder portion and the resin substrate includes a contact surface along an axis extending in a plate thickness direction of the resin substrate, and the other of the holder portion and the resin substrate includes a pressing surface that presses the contact surface.

A method for manufacturing an optical element according to the present disclosure includes, a first step of, after affixing a hologram forming material to a glass substrate having a marking portion, performing interference exposure on the hologram forming material, thereby forming a hologram layer at the glass substrate, and a second step of affixing the hologram layer peeled off from the glass substrate to a plastic substrate having a first alignment mark, wherein in the second step, the first alignment mark on the plastic substrate, and a second alignment mark formed at a position corresponding to the marking portion in the hologram layer during the interference exposure are used to implement positioning of the plastic substrate and the hologram layer.