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 holographic display system and a holographic display method are disclosed. By utilizing the shift of at least one of the light source module and the spatial light modulator, a holographic image can be provided to a plurality of stationary or moving observers over a wide range. The holographic display system includes a light source module for generating a coherent beam; a spatial light modulator for generating a holographic image using the coherent beam; a position detecting device for detecting an eye position of at least one observer; and an actuating device capable of shifting at least one of the light source module and the spatial light modulator based on the eye position of the at least one observer, thereby projecting the holographic image to the eye position of the at least one observer.

A backlight unit (BLU), for a binocular holographic display apparatus, and the binocular holographic display apparatus including the BLU are provided. The BLU includes: a light source unit that emits coherent illumination light; and a light guide plate that is transparent and includes a light incidence surface onto which the coherent illumination light emitted by the light source unit is incident and a light emission surface through which the illumination light is output. The light source unit includes a beam deflector that adjusts an incidence angle of the illumination light incident onto the light guide plate.

An image display system includes a reflecting screen that has a reflecting surface. The reflecting surface includes hologram which reflects narrow bands of spectrum of incident lights toward desired direction. A projection display system includes a reflecting mirror(s) with hologram so that the image can be projected nearly vertical or short distance. This invention can be used as a head-up-display with improved brightness and eliminating ghost noise.

A method for directing non-modulated light from a Spatial Light Modulator (SLM) and allowing through modulated light for producing an interference based holographic image, the method including illuminating the SLM with coherent light, thereby producing a mix of light modulated by the SLM and light not modulated by the SLM, and projecting the mix of the modulated light and the not modulated light along an optical axis onto a volume grating, wherein the volume grating directs the not modulated light away from the holographic image and allows through modulated light for producing the holographic image. Related apparatus and methods are also described.

Embodiments of the present disclosure include apparatuses and method for a stacked light emitting diode (LED) hologram display. A stacked LED hologram display can include a first array of LEDs that are configured to emit red light received by a meta-optics panel configured to display a first portion of a holographic image, a second array of LEDs that are configured to emit green light received by a meta-optics panel configured to display a second portion of a holographic image, and a third array of LEDs that are configured to emit blue light received by a meta-optics panel configured to display a third portion of a holographic image. The stacked LED hologram display can include a number of actuators configured to adjust a position of a first array of LEDs in first direction and a second direction, adjust a position of a second array of LEDs in the first direction and the second direction, and adjust a position of a third array of LEDs in the first direction and the second direction.

The invention relates to a method for observing a sample, in particular an anatomopathological slide formed from a thin thickness of a sampled biological tissue. It includes a step of illuminating the sample with a light source and acquiring, with an image sensor, an image representing the light transmitted by the sample. The image undergoes holographic reconstruction, so as to obtain a representation, in the plane of the sample, of the light wave transmitted by the latter. The method includes applying an impregnating fluid to the sample, such that the sample is impregnated with said impregnating liquid, said impregnating liquid having a refractive index strictly higher than 1.

Proposed are an image reproduction device, an image reproduction method, and a digital holography device, by which the calculation load is reduced and a time required to reproduce an object image from hologram image data is shortened, compared with a conventional technology. An image reproduction device (17) can reproduce an object image or a phase image thereof from hologram image data without performing conventional two-dimensional Fourier transform or two-dimensional inverse Fourier transform. Since no two-dimensional Fourier transform or no two-dimensional inverse Fourier transform is performed, the calculation load can be accordingly reduced, and a time required to reproduce an object image from hologram image data can be accordingly shortened, compared with a conventional technology.

Examples are disclosed herein relating to an adjustable scanning system configured to adjust light from an illumination source on a per-pixel basis. One example provides an optical system including an array of light sources, a holographic light processing stage comprising, for each light source in the array, one or more holograms configured to receive light from the light source and diffract the light, the one or more holograms being selective for a property of the light that varies based upon the light source from which the light is received, and a scanning optical element configured to receive and scan the light from the holographic light processing stage.

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.