Stimulus-responsive dynamic meta-holographic device
This disclosure relates to a stimulus-responsive dynamic meta-holographic device. According to an aspect of the disclosure, a stimulus-responsive dynamic meta-holographic device can be provided, which includes a metasurface in which a plurality of nanostructures are provided; wherein in the metasurface is provided a liquid crystal layer comprising a plurality of cells that may be altered in arrangements by outer stimulus, wherein the liquid crystal layer, is configured to alter the polarization state of the transmitted beam penetrating the liquid crystal layer as the arrangements of the cells are altered by outer stimulus.
1 . A hologram generating apparatus comprising:
a processing unit configured to receive source data of a source image and use angular momentum of a first beam representing the source data to generate data for producing a generated image comprising the source data; and
a database unit connected to a processing unit configured to store reference data for processing the generated data; and
a beam-generating unit connected to the processing unit forming the generated image by projecting a second beam according to the processed generated data,
wherein the processing unit comprising a Fourier processing unit configured to process value of Fourier Transform by multiplying a 2D Dirac comb function and a diffuser array with the source data.
2 . The hologram generating apparatus of claim 1 , wherein the source image is provided as a digital file format.
3 . The hologram generating apparatus of claim 1 , wherein the processing unit comprising an Inverse Fourier Processing Unit configured to process amplitude of a source image and Inverse Fourier Transform phase by Inverse Fourier Transforming the value of Fourier Transform.
4 . The hologram generating apparatus of claim 3 , wherein the processed amplitude and phase are expressed as complex-amplitude field value.
5 . A hologram generating apparatus of claim 3 , wherein the processing unit comprising a phase plate processing unit configured to add phase of the angular momentum to the processed amplitude and phase.
6 . The hologram generating apparatus of claim 5 , wherein the phase plate processing unit adds a lens phase corresponding to focal length of space where a generated image is generated, to the amplitude and phase with the phase of the angular momentum added.
7 . The hologram generating apparatus of claim 6 , wherein a plurality of the generated images is provided; and
wherein in the processing unit comprising a phase plate superposition unit configured to process the amplitude and phase of each of a plurality of source images, and adds and superposes the phase of the angular momentum and the lens phase.
8 . The hologram generating apparatus of claim 1 , wherein the beam-generating unit, is created according to the generated data processed by the processing unit; and
is provided as a phase plate or a beam modulator formed on a metasurface.
9 . A hologram generating method comprising:
a step (a) in which source data of a source image is conveyed to a processing unit;
a step (b) in which the processing unit processes generated data to generate a generated image comprising the source data using angular momentum of a first beam which represents the conveyed source data; and
a step (c) in which a beam-generating unit projects a second beam according to the processed generated data and generates the generated image in a space,
wherein the step (b), comprising:
a step (b1) in which a Fourier processing unit multiplies a 2D Dirac comb function and diffuser array to the source data to process value of Fourier Transform; and
a step (b2) in which an Inverse Fourier unit Inverse Fourier Transforms the value of Fourier Transform to process amplitude and phase.
10 . The hologram generating method of claim 9 , wherein the step (a) comprising a step (a1) in which more than one source image is selected.
11 . The hologram generating method of claim 9 , wherein the processed amplitude and phase are expressed in complex-amplitude field values.
12 . The hologram generating method of claim 9 , wherein the step (b) is comprising:
a step (b3) in which angular momentum is added to the amplitude and phase processed by a phase plate processing unit; and
a step (b4) in which the phase plate processing unit further adds focal length of a space for a generated image to be generated, to the amplitude and phase with the angular momentum added.
13 . The hologram generating method of claim 12 , wherein the step (b) is provided a plurality of source images, and is comprising a step (b5) in which a phase plate superposition unit processes each of the amplitude and phase of each of the plurality of the source images, and adds and superposes the phase of the angular momentum and the phase of the lens phase.
14 . The hologram generating method of claim 9 , wherein in the step (c) is comprising:
a step (c1) in which when the beam-generating unit is provided as a metasurface, the processed generated data corresponding to a phase plate is implemented as the metasurface; and
a step (c2) in which the beam-generating unit projects the second beam on the metasurface to and the generated image is generated in the space.
15 . The hologram generating method of claim 9 , wherein in the step (c) is included:
a step (c3) in which when the beam-generating unit is provided as a beam modulator, the second beam is projected by the beam modulator according to the processed generated data and the generated image is generated in the space.