Fast time-division color electroholography using a
multiple-graphics processing unit cluster system with a
single spatial light modulator
Hiromitsu Araki
1
, Naoki Takada
2,
*, Shohei Ikawa
3
, Hiroaki Niwase
1
, Yuki Maeda
1
,
Masato Fujiwara
1
, Hirotaka Nakayama
4
, Minoru Oikawa
2
, Takashi Kakue
5
,
Tomoyoshi Shimobaba
5
, and Tomoyoshi Ito
5
1
Graduate School of Integrated Arts and Sciences, Kochi University, Kochi, 780-8520, Japan
2
Science Department, Natural Sciences Cluster, Research and Education Faculty, Kochi University,
Kochi 780-8520, Japan
3
Faculty of Science, Kochi University, Kochi 780-8520, Japan
4
Center for Computational Astrophysics, National Astronomical Observatory of Japan, Mitaka-shi 181-8588, Japan
5
Graduate School of Engineering, Chiba University, Chiba 263-8522, Japan
*Corresponding author: ntakada@is.kochi‑u.ac.jp
Received August 28, 2017; accepted October 20, 2017; posted online November 14, 2017
We demonstrate fast time-division color electroholography using a multiple-graphics-processing-unit
(GPU) cluster system with a spatial light modulator and a controller to switch the color of the reconstructing
light. The controller comprises a universal serial bus module to drive the liquid crystal optical shutters. By using
the controller, the computer-generated hologram (CGH) display node of the multiple-GPU cluster system
synchronizes the display of the CGH with the color switching of the reconstructing light. Fast time-division
color electroholography at 20 fps is realized for a three-dimensional object comprising 21,000 points per color
when 13 GPUs are used in a multiple-GPU cluster system.
OCIS codes: 090.1705, 090.5694, 090.1760.
doi: 10.3788/COL201715.120902.
Holography
[1]
is the ideal three-dimensional (3D) display
technology because it can record and appropriately recon-
struct a 3D object. A computer-generated hologram
(CGH)
[2]
is digitally generated holographic interference
patterns between the scattered light from a 3D object
and reconstructing light. Electroholography using CGH
can reconstruct 3D movies using a spatial light modulator
(SLM). Therefore, electroholography has the potential
to ultimately realize a 3D television (TV)
[3,4]
. However,
the practical use of real-time electroholography is limited
by the complexity of the CGH calculations and the neces-
sity of high-performance computational power
[5]
.
A graphics processing unit (GPU) offers high perfor-
mance at low cost. A GPU code for general numerical
calculations can be created with the provided software
development kit (SDK). Fast CGH calculations using
GPUs have been demonstrated
[6–20]
.
Color electroholography is indispensable for realizing
a 3D TV. Color electroholography using three SLMs
for red, green, and blue (RGB) -colored lights has been
reported
[21–23]
. However, SLMs are expensive, and a system
containing three SLMs is very large. Color electroh ologra-
phy using a single SLM has also been investigated. The
space-division method
[24]
, depth-division method
[25,26]
,
and time-division method
[27–30]
have been proposed. In
the space-division method and the dep th-division method,
there is the advantage that flicker does not occurred.
However, it is not easy for the space-division method to
reconstruct clear color 3D images comprising many object
points, because a CGH comprises three parts for the RGB-
colored reconstructing lights. The reconstructed 3D image
by the depth-division method is slightly contaminated
by unwanted diffracted images. While flicker occurs for
time-division color electroholography using the proposed
system, the resolution power of the reconstructed 3D
image is high.
Figure
1 shows the outline of time-division electro-
holography. At each frame of a color-reconstructed 3D
movie, three CGHs for the RGB-colored lights are dis-
played on an SLM at regular time intervals. The 3D color
image is generated by time-division multiplexing of the
RGB-colored 3D images reconstructed from the CGHs.
Fig. 1. Outline of time-division color electroholography.
COL 15(12), 120902(2017) CHINESE OPTICS LETTERS December 10, 2017
1671-7694/2017/120902(4) 120902-1 © 2017 Chinese Optics Letters