An optical waveguide is provided. The optical waveguide includes a base structure and a plurality of grating structures disposed at the base structure. The grating structures include a plurality of in-coupling grating structures configured to couple a plurality of lights into the optical waveguide. At least one of a grating period or a slant angle of a first in-coupling grating structure is different from at least one of a corresponding grating period or a corresponding slant angle of a second in-coupling grating structure. The grating structures also include a plurality of out-coupling grating structures configured to couple the lights out of the optical waveguide.

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.

There are provided holographic optical elements (HOEs) and methods of making the same. An example of such methods includes recording a first hologram in a contiguous holographic recording medium of the HOE. The first hologram may receive a beam of light and direct at least a portion of the beam into a light guide to form an incoupled beam. The method also includes recording a second hologram in the contiguous holographic recording medium. The second hologram may receive at least a portion of the incoupled beam and direct the portion of the incoupled beam out of the light guide to form an outcoupled beam. In addition, the method includes affixing the holographic recording medium to the light guide.

The invention relates to a light modulation device for a display for representing two- and/or three-dimensional image content or image sequences. The light modulation device comprises a light modulator and a controller. The phase and/or the amplitude of a light wave field, which is substantially collimated, can be varied by means of the light modulator depending on the location of the light modulator. The light modulator can be actuated by means of the control device. According to the invention, in the direction of propagation of the light wave field, at least one diffracting unit is arranged downstream of the light modulator. The diffracting unit has a variable diffracting structure. By means of the diffracting structure, the light wave field varied by the light modulator can be diffracted in a variable and predeterminable manner. Further, the present invention relates to a display and a method for producing a light modulation device.

A filter device for an optical sensor, including a hologram having a defined number of holographic functions, which are developed in such a way that the filter device blocks optical radiation that impinges upon the filter device from a defined first solid angle and optical radiation that impinges upon the filter device from a defined second solid angle is able to pass through the filter device.

A display device is configured to be operable in a normal mode that blocks ambient light or a see-through mode that allows ambient light to be visible to a user. The display device includes an emission surface configured to output image light, a switchable window configurable to block ambient light in the normal mode or to transmit ambient light in the see-through mode, and an optical assembly. The optical assembly includes a first region configured to receive image light from the emission surface and to direct the image light toward the eyes of a user. The optical assembly also includes a second region configured to receive ambient light from the switchable window and to allow at least a portion of the ambient light to pass through. A method of setting the display device in normal mode or see-through mode is also disclosed.

Systems and methods for fabricating optical elements in accordance with various embodiments of the invention are illustrated. One embodiment includes a method for fabricating an optical element, the method including providing a first optical substrate, depositing a first layer of a first optical recording material onto the first optical substrate, applying an optical exposure process to the first layer to form a first optical structure, temporarily erasing the first optical structure, depositing a second layer of a second optical recording material, and applying an optical exposure process to the second layer to form a second optical structure, wherein the optical exposure process includes using at least one light beam traversing the first layer.

The disclosure provides for a display apparatus for a vehicle for displaying images captured by at least one image sensor to a driver of the vehicle. The display apparatus includes a display projector configured to project images derived from the image data, a display screen for displaying images projected thereon by the display projector, and a reflector positioned to reflect the images from the display screen towards a viewing direction. According to one embodiment, the display apparatus further includes an adjustment mechanism for adjusting the display projector relative to the vehicle. According to another embodiment, the display apparatus further includes a frame assembly on which the display projector, the display screen, and the reflector are mounted, the frame assembly is mounted to the vehicle such that the frame assembly may be moved relative to the vehicle to adjust the positions of the display projector, the display screen, and the reflector.

Multiple pairs of substrate-guided wave-based holograms (SGWHs) are laminated to a common thin substrate to form a transparent substrate-guided wave-based holographic CHMSL (SGWHC) that diffracts playback LED illumination over a wide angular range. This device is made pursuant to a technique that includes the steps of recording a first set of SGWHs with one setup, that upon playback, will couple and guide the diffracted light inside the substrate, and a second set of SGWHs recorded with another setup, that will diffract and couple the guided light out.

The invention relates to a light modulation device for a display for representing two- and/or three-dimensional image content or image sequences. The light modulation device comprises a light modulator and a controller. The phase and/or the amplitude of a light wave field, which is substantially collimated, can be varied by means of the light modulator depending on the location of the light modulator. The light modulator can be actuated by means of the control device. According to the invention, in the direction of propagation of the light wave field, at least one diffracting unit is arranged downstream of the light modulator. The diffracting unit has a variable diffracting structure. By means of the diffracting structure, the light wave field varied by the light modulator can be diffracted in a variable and predeterminable manner. Further, the present invention relates to a display and a method for producing a light modulation device.