COL 11(1), 010901(2013) CHINESE OPTICS LETTERS January 10, 2013
3D displays: toward holographic video displays
of 3D images
Pochi Yeh
1
and Claire Gu
2∗
1
Electrical and Computer Engineering, University of California Santa Barbara, California 93106, USA
2
Electrical Engineering University of California Santa Cruz, California 95064, USA
∗
Corresponding author: claire@soe.ucsc.edu
Received October 30, 2012; accepted November 19, 2012; posted online Decemb er 26, 2012
As the flat panel d isplays (Liquid Crystal Displays, AMOLED, etc.) reach near perfection in their viewing
qualities and display areas, it is natural to seek the next level of displays, including 3D displays. There is
a strong surge in 3D liquid crystal displays as a result of the successful movie Avatar. Most of these 3D
displays involve t he employment of special glasses that allow one view perspective for each of the eyes to
achieve a depth perception. Such displays are n ot real 3D displays. In fact, these displays can only provide
one viewing perspective for all viewers, regardless of the viewer’s position. In addition, a fundamental
viewing problem of focusing and accommodation exist that can lead to discomfort and fatigue for many
viewers. I n this paper, the authors review the current status of stereoscopic 3D displays and their problems.
The authors will also discuss the possibility of using flat panels for the display of both phase and intensity
of video image information, leading to the ultimate display of 3D holographic video images. Many of the
fundamental issues and limitations will be presented and di scussed.
OCIS codes: 090.0090, 090.2870.
doi: 10.3788/COL201311.010901.
1. Introduction
Display of information or images is an important part
of our daily lives. As a result of their light weig ht, high
quality and low power consumption, flat panel displays,
especially liquid crystal displays (LCDs) are becoming
the dominant display systems for mobile devices, home
televisions and computer mo nitors. The success is a
result of many contributing factors. These include the
development of liquid crystal (LC) materials that o ffer
a large e le c tro-optical effect at low driving voltages, the
development of active-matrix addressing using arrays of
semiconductor thin film transistors (TFTs), the devel-
opment of large ar e a thin film poly mers with supe rior
birefringent optical properties, a good understanding
of the transmission of polarized light in LCDs, and a
growing demand for high-quality flat-panel displays in
a broad area o f applications, etc
[1−3]
. In the early days
of liquid crystal displays, the viewing quality (in terms
of contrast ratio and color stability) degrades at large
viewing a ngles. This is mainly due to the leakage of
light at the dark state of the display. The technology of
polarization interference filters using birefringent crys-
tals developed earlier for a strophysics plays a key role
in the design of optical compensators for the impr ove-
ment of viewing quality in LCDs
[2,3]
. In recent years, the
defect problems in active-matrix organic light emitting
displays (AMOLED) are mostly resolved. By virtue of
its light emission nature, there is no leakage problem in
AMOLED. As a re sult, AMOLEDs are capable of dis-
playing high quality images with superior color stability
and contrast ratios. Furthermore, the fast response of the
emission process in AMOLEDs eliminates the pro blem
of motion blur that occurs in LCDs. Flat panel displays,
dominated by liquid crystal displays, are reaching near
perfection in both the viewing qualities and display ar-
eas. The next generation flat panel displays should be
able to display real 3D video images.
2. Current 3D displays and issues
3D movies that require special glasse s have be e n around
for over a hundred years. The recent success in liquid
crystal displays, retardation films and polarizers makes
it possible for the development of flat pa nel stereoscopic
3D video images. In addition, high speed scanning of
laser beams can be employed for the volumetric display
of 3D images
[4]
. Image pixels of a 3D object are projected
via a scanning laser beam on a diffuser screen which is
spun at high speed. The volumetric display of 3D im-
ages, however, requires a cubic vo lume of space needed
to accommodate the spinning of the diffuser screen.
The stereosco pic display of 3D images can be achieved
via a flat panel (e.g., LCD panel) in conjunction with a
pair of special glasses that consist of synchronized shut-
ters, orthogonal polarizers or color filters. Special glasses
are not needed in auto-stereo scopic 3D display panels.
However, the image quality is severely deg raded in such
displays. Fundamental problems exist in the viewing of
stereoscopic 3D display of images. In stereoscopic 3D
displays, two images are displayed either in sequence or
simultaneously in different polarization states, one for
each of the e yes. The viewer s must focus (accommodate)
their eyes on the screen where the light of the two images
comes from. At the same time, the eyes must converge
to the apparent location of the 3D image which can be
either in front of the screen of behind the screen. Such a
simultaneous effort of trying to converge and to accom-
modate with a different distance is a major source of eye
discomfort and fatigue
[5,6]
.
From the fundamental point of view, the stereoscopic
display of 3D images provides only a depth perception.
1671-7694/2013/010901(7) 010901-1
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2013 Chinese Optics Letters