Samsung Electronics Co., Ltd.

Korea University Research and Business Foundation

Snur & Db Foundation

Chilsung Choi

Hongseok Lee

Hoon Song

Jungkwuen An

Sunil Kim

German B Dubinin

Young Shin Kim

Kanghee Won

Yunhee Kim

Sergey E Dubynin

Alexander Victorovich Morozov

Andrey Nikolaevich Putilin

Geeyoung Sung

Sunghoon Lee

Aleksander V Morozov

Joonyong Park

Sergey S Kopenkin

Yuriy P Borodin

Hwi Dae Kim

Wontaek Seo

Jong-Young Hong

Juwon Seo

Changkun Lee

Yuntae Kim

Young Ju Kim

Byonggwon Song

Woohyuk Jang

Young Kyoo Kim

Dukho Lee

Taekdong Chung

Vladimir V Shelkovnikov

Evgeny V Vasiliev

Vladimir Loskutov

Songhoon Lee

Provided is a waveguide structure including an output grating, a polarization conversion element provided parallel to the output grating, and a polarization separation element provided between the output grating and the polarization conversion element, wherein the polarization separation element is configured to transmit, to the output grating, light having a first polarization direction among light incident on the polarization separation element, and reflect, to the polarization conversion element, light having a second polarization direction different from the light having the first polarization direction among the light incident on the polarization separation element.

Waveguide structure, back light unit including the same, and display apparatus including the waveguide structure

A backlight unit may include: a light source providing coherent light; a light guide plate having a light entrance surface on which light from the light source is incident and a light exit surface through which the light is output; a plurality of diffraction gratings (for example, a first input grating, a second input grating, and a third input grating) that are arranged in different regions of the light guide plate to sequentially diffract the light from the light source such that that the beam width of the light may increase as the light propagates in the light guide plate; and a diffraction grating (for example, an output grating) that diffracts and outputs the light having an increased beam width in a direction toward the outside of the light guide plate.

Backlight unit and holographic display apparatus including the same

A beam expander includes first and second optical elements spaced apart from each other, and a light diffuser having an angular aperture that diffuses incident light through the angular aperture, wherein the first optical element in-couples the diffused light such that light exiting the first optical element has a first cross-sectional shape and light having a second cross-sectional shape different from the first cross-sectional shape is incident on the second optical element, and the second optical element out-couples light incident from the first optical element.

Beam expander and method of operating the same

Provided is a holographic display apparatus including: a spatial light modulator that modulates a wavefront of a reference beam to form a hologram image; an optical element arranged to change a position of a viewing window of the hologram image off-axis by a first angle; and an image processor that generates hologram data according to the position of the viewing window of the hologram image and a hologram image to be reproduced, and provides the hologram data to the spatial light modulator. The hologram image formed by the spatial light modulator is viewable from a side of the spatial light modulator.

Holographic display apparatus

A beam deflection apparatus includes a first beam deflector that deflects light in a first direction and a second beam deflector that deflects light in a second direction perpendicular to the first direction, wherein the first beam deflector and the second beam deflector each include a first region for deflecting light of a first wavelength and a second region for deflecting light of a second wavelength, and a ratio of a spatial period of a signal applied to first drive electrodes arranged in the first region of the first beam deflector to the first wavelength is the same as a ratio of a spatial period of a signal applied to second drive electrodes arranged in the second region of the first beam deflector to the second wavelength.

Beam deflection apparatus and holographic display apparatus including the same

There is provided a beam expander including a first optical element, a second optical element, a composite waveguide including a plurality of waveguide elements, and a dichroic coating provided between the plurality of waveguide elements. The first optical element inputs a collimated incident beam from the outside into the composite waveguide, and the second optical element outputs, from the composite waveguide, collimated incident beam, input to the composite waveguide, wherein the collimated incident beam input into the composite waveguide is divided into multiple wavefronts by the dichroic coating, and the multiple wavefronts are mixed by total internal reflection in the composite waveguide. When the beam expander is used, coherency and collimation of an output beam may be maintained and speckles may be reduced or eliminated while improving the efficiency of an optical system.

Beam expander and beam expansion method

A holographic display device includes a light source configured to emit light, the light including first light of a first wavelength, second light of a second wavelength, and third light of a third wavelength; a spatial light modulator configured to form a holographic pattern to modulate the light emitted from the light source and to produce a holographic image; and a focusing optical system configured to focus the holographic image. The focusing optical system includes a fixed-focus optical system having a fixed focal length, and a variable focus optical system having a focal length that is changed by electrical control. The fixed-focus optical system is configured to focus the first light of the first wavelength, the second light of the second wavelength, and the third light of the third wavelength on different positions, respectively, on an optical axis to cancel a chromatic aberration by the variable focus optical system.

Holographic display device having reduced chromatic aberration

Provided are holographic displays and operating methods of the holographic display. The holographic display includes a backlight portion configured to emit light for displaying an image; a deflector configured to control a direction at which the image is displayed; a lens portion configured to control a location where the image to be displayed is formed to match a location that satisfies a diffraction condition; and a panel portion configured to display a 3D image by combining the image to be displayed with an interference pattern generated with respect to an overlapped hologram.

Holographic display and operating method thereof

Provided a backlight unit including a light source and a light guide structure configured to guide the light emitted from the light source, the light guide structure includes a first coupler layer including a first output coupler configured to expand light in a first direction and output the expanded light in the first direction to the outside of the light guide structure, and a first expansion coupler configured to expand the light in a second direction perpendicular to the first direction and provide the expanded light in the second direction to the first output coupler, and a second coupler layer including a second output coupler configured to expand light in the first direction and output the expanded light to the outside of the light guide structure, and a second expansion coupler configured to expand light in the second direction and provide the expanded light to the second output coupler.

A holographic display apparatus capable of providing an expanded viewing window and a display method are provided. The holographic display apparatus includes an image processor configured to provide computer generated hologram (CGH) data to a spatial light modulator, wherein the image processor is further configured to generate a hologram data array comprising information of the holographic image to be reproduced at the first resolution or a resolution less than the first resolution, perform an off-axis phase computation on the hologram data array at the second resolution, and then, generate the CHG data at the first resolution.

Holographic display apparatus and method for providing expanded viewing window

A holographic display device including a field lens focusing a three-dimensional (3D) image reproduced by a holographic display, wherein the field lens includes an anisotropic diffractive lens functioning as a lens with respect to a specific polarization.

Holographic display device capable of reducing chromatic aberration

A backlight unit and a holographic display apparatus including the same are provided. The backlight unit includes a light guide plate and a uniformity changing element. The uniformity changing element has a light-incident surface and a light-exiting surface facing the light-incident surface, and the uniformity changing element receives the light output from the light guide plate through the light-incident surface, changes uniformity of the received light from the light guide plate and outputs the received light with the change in the uniformity of the received light through the light-exiting surface.

Provided are methods of processing a holographic image and apparatuses using the methods. A method includes obtaining image data with respect to a three-dimensional (3D) object, obtaining interference patterns in a computer-generated hologram (CGH) plane by performing a Fourier transform on the image data, and generating a CGH with respect to the 3D object based on the interference patterns, wherein the Fourier transform is performed based on a focal length of an eye lens of an observer.

Growing community of inventors

Suwon-si, South Korea

Chilsung Choi