Abstract: Provided is a device configured to enlarge an exit pupil area of a visual optical apparatus, the device including a diffraction grating configured to output a plurality of diffracted light beams of a plurality of diffraction orders by diffracting an incident light beam, and a waveguide provided on the diffraction grating and configured to form an exit pupil based on a first diffracted light beam among the plurality of diffracted light beams output from the diffraction grating and to form exit pupil orders based on a second diffracted light beam among the plurality of diffracted light beams output from the diffraction grating.

Abstract: Provided is a device configured to enlarge an exit pupil area of a visual optical apparatus, the device including a diffraction grating configured to output a plurality of diffracted light beams of a plurality of diffraction orders by diffracting an incident light beam, and a waveguide provided on the diffraction grating and configured to form an exit pupil based on a first diffracted light beam among the plurality of diffracted light beams output from the diffraction grating and to form exit pupil orders based on a second diffracted light beam among the plurality of diffracted light beams output from the diffraction grating.

Abstract: Provided is a backlight unit including a light source emitting coherent light, a light guide plate propagating the light emitted by the light source, an input grating inputting the light from the light source into the light guide plate, an output grating provided on one surface of the light guide plate and diffracting light incident from inside the light guide plate and outputting the light, in a direction toward the outside of the light guide plate, a first recuperation element provided on one surface of the light guide plate and including a first recycle grating, and a second recuperation element provided opposite to the first recuperation element and directing, to the first recuperation element, incident light that is propagating inside the light guide plate.

Abstract: Provided is a backlight unit including a light source emitting coherent light, a light guide plate propagating the light emitted by the light source, an input grating inputting the light from the light source into the light guide plate, an output grating provided on one surface of the light guide plate and diffracting light incident from inside the light guide plate and outputting the light, in a direction toward the outside of the light guide plate, a first recuperation element provided on one surface of the light guide plate and including a first recycle grating, and a second recuperation element provided opposite to the first recuperation element and directing, to the first recuperation element, incident light that is propagating inside the light guide plate.

Abstract: A backlight unit for a holographic display is provided. The backlight unit includes: at least one light source; at least one input coupler; a light guide panel (LGP) that guides light; a first holographic element on a first surface of the LGP; and a second holographic element on a second surface of the LGP, wherein the at least one input coupler is configured to uniformly transmit rays emitted from the at least one light source toward the first holographic element through the LGP, and the LGP is configured to transmit the rays incident from the at least one input coupler toward the first holographic element, and the first holographic element redirects the rays toward the second holographic element, the redirected rays being substantially parallel to one another, and the second holographic element emits rays incident from the first holographic element toward an outside of the LGP.

Abstract: 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.

Abstract: 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.

Abstract: A backlight unit for a holographic display is provided. The backlight unit includes: at least one light source; at least one input coupler; a light guide panel (LGP) that guides light; a first holographic element on a first surface of the LGP; and a second holographic element on a second surface of the LGP, wherein the at least one input coupler is configured to uniformly transmit rays emitted from the at least one light source toward the first holographic element through the LGP, and the LGP is configured to transmit the rays incident from the at least one input coupler toward the first holographic element, and the first holographic element redirects the rays toward the second holographic element, the redirected rays being substantially parallel to one another, and the second holographic element emits rays incident from the first holographic element toward an outside of the LGP.