The invention relates to a display device for holographic reconstruction. The display device comprises a spatial light modulator device having combined phase modulating pixels and amplitude modulating pixels, an illumination unit generating sufficiently coherent light and arranged to illuminate of the spatial light modulator device and a reflection plane. The device being arranged such that light enters the spatial light modulator device and passes both the phase modulating pixel and the amplitude modulating pixel of the spatial light modulator device. The light is reflected by the reflection plane in between.

A system includes a laser emitting a laser beam, a beam expander expanding the laser beam, a beam splitter prism splitting the expanded laser beam into first and second split light beams, a liquid crystal box containing polymer-dispersed liquid crystal, first and second reflectors reflecting the first and second split light beams to the liquid crystal box, respectively, and an attenuator arranged on an optical path between the beam expander and the liquid crystal box. The attenuator gradually attenuates at least one of the laser beam, the expanded laser beam, the first split light beam, or the second split light beam along a first set curve. The first split light beam and the second split light beam form interference fringes at the liquid crystal box to expose the polymer-dispersed liquid crystal to form a polymer-dispersed liquid crystal holographic grating having a diffraction efficiency decreasing along a second set curve.

Methods, systems, and devices for particle characterization by optical phase modulation and detection of aerosol backscattering. In some aspects, a compact and cost effective particle detector device to measure the aerosol density and its size distribution by backscattered focusing using projected optical modified field distribution imaging into the aerosol medium (air). The disclosed device can be used in a variety of scientific and industrial applications, e.g., such as a particle sensor for automobiles able to detect harmful pollution which may then be filtered from the car cabin, or warnings provided to the driver. The device can also capture and store data, enabling detailed pollution maps of various roadways in real-time.

The invention refers to an Illumination device for illuminating a spatial light modulator device. Sub-holograms are used for encoding a hologram into the spatial light modulator device. The Illumination device comprises at least one light source for emitting light for illuminating the spatial light modulator device and a beam shaping unit. The beam shaping unit provides a flat-top plateau-type distribution of an absolute value of a complex degree of mutual coherence of the light in a plane of the spatial light modulator device to be illuminated. The flat-top plateau-type distribution of the absolute value of the complex degree of mutual coherence has a shape that is at least similar to a shape of the largest sub-hologram used for encoding of object points into the spatial light modulator device.

A holographic projector includes an illumination system arranged to illuminate a hologram displayed on the pixel area of a spatial light modulator to form a holographic wavefront, and further includes a waveguide including an input port arranged to receive the holographic wavefront and a pair of opposing surfaces arranged to waveguide the holographic wavefront. A first surface of the pair of opposing surfaces is partially reflective-transmissive such that a plurality of replicas of the holographic wavefront are emitted therefrom. The illumination system includes a light source arranged to emit diverging light and a first collimating lens arranged to collimate the light. The collimated light has a varying intensity profile, in at least one dimension. The illumination system is configured such that the pixel area is contained within an area delineated by the width of the intensity profile of the collimated light at half the maximum intensity of said intensity profile.

A polarization diffraction element comprising including a film including a liquid crystalline material having photosensitivity, the film having at least one hologram recorded therein, and thereby having a property as a fork-shaped polarization grating having an anisotropic structure in which an optical axis continuously rotates toward a direction of a grating vector.

Methods, systems, and devices for particle characterization by optical phase modulation and detection of aerosol backscattering. In some aspects, a compact and cost effective particle detector device to measure the aerosol density and its size distribution by backscattered focusing using projected optical modified field distribution imaging into the aerosol medium (air). The disclosed device can be used in a variety of scientific and industrial applications, e.g., such as a particle sensor for automobiles able to detect harmful pollution which may then be filtered from the car cabin, or warnings provided to the driver. The device can also capture and store data, enabling detailed pollution maps of various roadways in real-time.

A device in holographic imaging comprises: at least two light sources, wherein each of the at least two light sources is arranged to output light of a unique wavelength; and at least one holographic optical element, wherein the at least two light sources and the at least one holographic optical element are arranged in relation to each other such that light from the at least two light sources incident on the at least one holographic optical element interacts with the at least one holographic optical element to form wavefronts of similar shape for light from the different light sources.

An illumination device for illuminating a spatial light modulator device. Sub-holograms are used for encoding a hologram into the spatial light modulator device. The Illumination device includes at least one light source for emitting light for illuminating the spatial light modulator device and a beam shaping unit. The beam shaping unit provides a flat-top plateau-type distribution of an absolute value of a complex degree of mutual coherence of the light in a plane of the spatial light modulator device to be illuminated. The flat-top plateau-type distribution of the absolute value of the complex degree of mutual coherence has a shape that is at least similar to a shape of the largest sub-hologram used for encoding of object points into the spatial light modulator device.

Provided/Disclosed is a holographic display device including a light source configured to output a coherent emission beam, a beam illuminator configured to convert the emission beam to an illumination light having a plane wavefront and a spatially regular intensity and output the converted emission beam, and a spatial light modulator (SLM) configured to display a holographic image by modulating the illumination light based on image information, wherein the beam illuminator is configured to converge and output the illumination light.