A display article (10) includes a plurality of display areas (12, and 13a to 13c). Display areas adjacent to each other differ in at least one of an average hue, an average brightness and an average chroma and a first object to be displayed (21) is formed by a combination of the plurality of display areas (12, and 13a to 13c). At least one of the display areas (12, 13a to 13c) includes a Fourier transform hologram (20R, 20Y) configured to convert incident ray from a point light source or a laser light source into a second object to be displayed.

An illumination device has a coherent light source, an optical device that diffuses the plurality of coherent light beams and illuminates a predetermined illumination area, and a timing control unit that individually controls incident timing of the plurality of coherent light beams to the optical device or illumination timing of the illumination area, wherein the optical device has a plurality of diffusion regions, the diffusion regions being provided corresponding to the plurality of coherent light beams, the plurality of diffusion regions illuminate the illumination range by diffusion of incident coherent light beams, the plurality of diffusion regions have a plurality of element diffusion regions, the plurality of element diffusion regions illuminate partial regions in the illumination area by diffusion of incident coherent light beams, and at least parts of the partial regions illuminated by the plurality of element diffusion regions are different from one another.

A display device includes a light source, a waveguide element, a liquid crystal coupler, a first holographic optical element and a second holographic optical element. The light source is configured to emit light. The waveguide element is located above the light source. The liquid crystal coupler is located between the waveguide element and the light source. The first holographic optical element is located on a top surface of the waveguide element, in which the liquid crystal coupler is configured to change an incident angle that the light emits to the first holographic optical element. The second holographic optical element is located on the top surface of the waveguide element, and there is a first distance in a horizontal direction between the first holographic optical element and the second holographic optical element, in which the second holographic optical element is configured to diffract the light to the waveguide element below.

A lighting device for vehicles, in particular a signal light, with a light source for emitting a light beam and an optical unit associated with the light source for producing a predetermined light function, the optical unit having a holographic element and a lens arranged in the main emission direction in front of the holographic element, the holographic element comprising such a diffraction structure that the light beam emitted from the light source onto the holographic element is varied according to a predetermined illumination pattern such that the holographic light beam lights an illumination surface of the lens to generate the light function.

A display system and a method of adjusting a display system are disclosed. A first plurality of pixels is arranged to display a first hologram, receive light of a first wavelength, and output spatially-modulated light according to the first hologram, along a first optical path. A first Fourier transform lens on the first optical path forms a first holographic reconstruction at a replay plane. A second plurality of pixels is arranged to display a second hologram, receive light of a second wavelength, and output spatially modulated light according to the second hologram, along a second optical path. A second Fourier transform lens on the second optical path forms a second holographic reconstruction at the replay plane. A first optical element on the first optical path is arranged to receive the output light from a first part of the first optical path and direct it along a second part of the first optical path to the replay plane. A second optical element on the second optical path is arranged to receive the output light of the second wavelength from a first part of the second optical path and direct it along a second part of the second optical path to the replay plane. The length of the first part of the first optical path is not equal to the length of the first part of the second optical path. The first part of the first optical path may he substantially collinear with the first part of the second optical path.

A display system and a method of adjusting a display system are disclosed. A first plurality of pixels is arranged to display a first hologram, receive light of a first wavelength, and output spatially-modulated light according to the first hologram, along a first optical path. A first Fourier transform lens on the first optical path forms a first holographic reconstruction at a replay plane. A second plurality of pixels is arranged to display a second hologram, receive light of a second wavelength, and output spatially modulated light according to the second hologram, along a second optical path. A second Fourier transform lens on the second optical path forms a second holographic reconstruction at the replay plane. A first optical element on the first optical path is arranged to receive the output light from a first part of the first optical path and direct it along a second part of the first optical path to the replay plane. A second optical element on the second optical path is arranged to receive the output light of the second wavelength from a first part of the second optical path and direct it along a second part of the second optical path to the replay plane. The length of the first part of the first optical path is not equal to the length of the first part of the second optical path. The first part of the first optical path may he substantially collinear with the first part of the second optical path.

Holographic and diffractive optical encoding techniques for forming reflection or transmission holograms. The encoding device includes a substrate having an interference pattern that can propagate light along a light propagation path from one side of the substrate to another side of the substrate. Furthermore, an optical element may be used to propagate light according to a four-dimensional light field coordinate system.

A digital holographic apparatus includes a first hologram generating unit that generates a first hologram by causing first object light in a first observation direction to interfere with first reference light, the first object light being generated by irradiating an observation object with light having a first wavelength, the first reference light being derived from the light having the first wavelength; a second hologram generating unit that generates a second hologram by causing second object light in a second observation direction that differs from the first observation direction to interfere with second reference light, the second object light being generated by irradiating the observation object with light having a second wavelength, the second reference light being derived from the light having the second wavelength; a first image capturing unit that captures the first hologram; and a second image capturing unit that captures the second hologram.

A digital holographic apparatus includes a first hologram generating unit that generates a first hologram by causing first object light in a first observation direction to interfere with first reference light, the first object light being generated by irradiating an observation object with light having a first wavelength, the first reference light being derived from the light having the first wavelength; a second hologram generating unit that generates a second hologram by causing second object light in a second observation direction that differs from the first observation direction to interfere with second reference light, the second object light being generated by irradiating the observation object with light having a second wavelength, the second reference light being derived from the light having the second wavelength; a first image capturing unit that captures the first hologram; and a second image capturing unit that captures the second hologram.

There is provided an optical structure having a quantization phase difference structure on one surface of a quantization phase difference structure layer, wherein in the quantization phase difference structure, a plurality of quantization projecting portions in a constant size and a plurality of quantization recessed portions in a constant size are aligned, wherein a multiple diffraction region has the quantization phase difference structure where ribbed projecting portions, in which the quantization projecting portions are aligned in one direction, are arranged adjacent to and alternately with groove-like recessed portions, in which the quantization recessed portions are aligned parallel to the ribbed projecting portions, and wherein the multiple diffraction region is a quantization phase difference structure configured to reproduce a plurality of reproduction points discrete in one direction and arranged regularly.