Apparatus for manufacturing holographic optical element, and apparatus for reconstructing holograms

Patent metadata

Field	Value
Publication number	US-11188026-B2
Application number	US-202016738658-A
Country	US
Kind code	B2
Filing date	Jan 9, 2020
Priority date	Nov 8, 2016
Publication date	Nov 30, 2021
Grant date	Nov 30, 2021

Abstract

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.

First claim

What is claimed is:

1. An apparatus for reconstructing a hologram, the apparatus comprising:
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;
a spatial light modulator; and
a light source configured to emit a first standard beam to the holographic optical element, corresponding to the first reference beam,
wherein the holographic optical element, in response to the first standard beam, reconstructs a first reconstruction beam corresponding to the first signal beam, and emits the first reconstruction beam to the spatial light modulator,
the spatial light modulator generates a second standard beam by modulating the first reconstruction beam according to hologram information, and emits the second standard beam to the holographic optical element, corresponding to the second reference beam, and
the holographic optical element reconstructs a holographic image by focusing the second standard beam in a space.

2. The apparatus of claim 1 , wherein energy of the modulated second signal beam and the second reference beam emitted during recording of the second interference pattern is set to be greater than energy of the first signal beam and the first reference beam emitted during recording of the first interference pattern.

3. The apparatus of claim 1 , wherein the first standard beam and the second standard beam satisfies a Bragg's matching condition with the first reference beam and the second reference beam, respectively.

4. The apparatus of claim 1 , wherein the hologram information is information about a computer-generated hologram.

5. The apparatus of claim 4 , wherein the second standard beam indicates a Fourier-transformed computer-generated hologram, and
the holographic optical element performs an inverse Fourier transform on the Fourier-transformed computer-generated hologram to generate the holographic image.

6. The apparatus of claim 1 , wherein the spatial light modulator generates the second standard beam by modulating the first reconstruction beam according to hologram information considering an angular difference between the spatial light modulator and the holographic optical element.

7. The apparatus of claim 1 , further comprising:
a plurality of polarized panels arranged in front of and in the rear of the spatial light modulator in a perpendicular direction with each other; and
a half bandpass filter.

Assignees

• Seoul Nat Univ R&Db Foundation

Inventors

• Lee Byoungho
• JEONG Youngmo
• Li Gang
• Lee Dukho

Classifications

• G03H1/0443

  Digital holography, i.e. recording holograms with digital recording means (holobject computation G03H1/0866) · CPC title

• G03H2001/0439

  for recording Holographic Optical Element [HOE] · CPC title

• G03H2001/045

  Fourier or lensless Fourier arrangement · CPC title

• G03H1/28

  superimposed holograms only · CPC title

• G03H1/2294

  Addressing the hologram to an active spatial light modulator · CPC title