A method is provided. The method includes directing a first beam to a polarization sensitive recording medium. The method also includes directing a second beam to the polarization sensitive recording medium to interfere with the first beam to generate a polarization interference pattern, to which the polarization sensitive recording medium is exposed. One of the first beam and the second beam has a planar wavefront and the other has a non-planar wavefront. A first propagation direction of the first beam and a second propagation of the second beam are non-parallel.

A method and apparatus for processing hologram image data capable of optimizing image quality of a hologram image are provided. The image processing method includes receiving input image data, reading a header included at a predetermined location in the input image data, and generating hologram data configured to display a hologram image by performing a Fourier calculation and pixel encoding on the input image data based on at least one parameter recorded in the header, wherein the at least one parameter recorded in the header includes at least one of depth information, scale information, and gamma information.

A focus modulation optical system and a holographic display device having the focus modulation optical system are disclosed. The holographic display device includes a light source configured to emit a plurality of color lights, a focus modulation optical system including at least one variable focus lens that is configured to change a focusing position of incident light by electrical control of the at least one variable focus lens based on a color of light incident on the variable focus lens, and a spatial light modulator configured to form a holographic image by diffracting light output from the focus modulation optical system.

A method of reconstructing a three-dimensional (3-D) image on the basis of a diffraction grating includes extracting parallax images from a raw image of an object photographed by using a diffraction grating and reconstructing a 3-D image from the extracted parallax image array by using a virtual pinhole model.

A camera includes, in part, an optical signal source generating a frequency varying optical signal, a multitude of pixels arranged along rows and columns, an optical focusing element, and an opto-electronic circuit. A portion of the optical signal generated by the optical signal is caused to reflect from a target object and then directed toward the pixels. A multitude of samples of a second portion of the optical signal are combined with the signals received by the pixels to generate a multitude of combined optical signals. The optical signals so combined are converted to electrical signals. Each electrical signal has a frequency defined by a difference between a frequency of the second portion of the optical signal and a frequency of a signal received from a pixel. The frequency differences are used to form an image of the target object.

A projection system that facilitates the use of in-situ detection of a change in wavelength, thereby enabling appropriate compensation or corrections to be applied on the fly to improve the quality of the image in the primary image region. In-situ detection in this manner can allow wavelength changes due to both temperature fluctuations and hardware variations to be compensated for simultaneously, thereby reducing the time and expense for end of line hardware testing, and removing the need to perform in-situ mapping of the wavelength as a function of temperature. In this way, the quality of the image provided to a user can be improved in a simpler, more efficient manner.

An apparatus for manufacturing a hologram includes a holographic optical element on which a first interference pattern of a first signal beam and a first reference beam is recorded and a second interference pattern of a second signal beam modulated by a Fourier lens and a second reference beam is recorded. Also, an apparatus for reconstructing a hologram by using the holographic optical element is provided.

An object of the present invention is to provide an image display device capable of easily detecting an eye gaze. The object is achieved by providing an image display optical system; an infrared light source that irradiates an eyeball of a user with infrared light; a hologram element that transmits infrared light emitted by the infrared light source and reflected by the eyeball of the user; and an infrared light image sensor that images infrared light transmitted through the hologram element, in which the hologram element acts on infrared light without acting on visible light and emits reproduced infrared light with an intensity distribution in a plane direction corresponding to an eye gaze of the user.

A method and apparatus for processing hologram image data capable of optimizing image quality of a hologram image are provided. The image processing method includes receiving input image data, reading a header included at a predetermined location in the input image data, and generating hologram data configured to display a hologram image by performing a Fourier calculation and pixel encoding on the input image data based on at least one parameter recorded in the header, wherein the at least one parameter recorded in the header includes at least one of depth information, scale information, and gamma information.

An apparatus for manufacturing a hologram includes a holographic optical element on which a first interference pattern of a first signal beam and a first reference beam is recorded and a second interference pattern of a second signal beam modulated by a Fourier lens and a second reference beam is recorded. Also, an apparatus for reconstructing a hologram by using the holographic optical element is provided.