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A PROTOTYPE MULTIVIEWER 3D TV DISPLAY
Phil Surman, Ian Sexton,
Richard Bates, Wing Kai Lee
IMAGING AND DISPLAYS RESEARCH GROUP
DE MONTFORT UNIVERSITY, LEICESTER, UK
3D TELEVISION REQUIREMENTS
 No Glasses (autostereoscopic)
 Must support multiple viewers
 Large viewing area
 Compact housing size
 Utilise readily-available technology
 Low(ish cost)
Autostereoscopic
Holographic
Volumetric
Multiple Image
Virtual
Holoform
Image Real
Multiview
Image
Binocular
3D DISPLAY
TAXONOMY
Fixed
Viewing
Zones
Head
Tracking
HOLOGRAPHIC
A holographic display is one where the image is
produced by wavefront reconstruction
The ideal stereoscopic display would produce
images in real time that exhibit all the
characteristics of the original scene. This
would require the reconstructed wavefront
to be identical and could only be achieved
using holographic techniques. The
difficulties of this approach are the huge
amounts of computation necessary to
calculate the fringe pattern, and the high
resolution of the display, which has to be
of the order of a wavelength of light (around
0.5 micron).
HOLOGRAPHY
Vertical
scanner
Horizontal
scanner
AOM
Imaging
lens
QinetiQ
MIT
OASLM
EASLM
Vertical
diffuser
Output
lens
HOLOGRAPHY
 Large complex hardware for small image
volume
 High computational overhead
 Naturally-lit scenes difficult
 Unlikely for next generation TV
 Maybe head tracking could be used
Volumetric
A volumetric display is one where the image is
produced within a volume of space, and the
space may be either real or virtual.
 Virtual image
 Real Image
• Swept volume
• Static volume
VOLUMETRIC
Virtual Image
Swept Volume
Static Volume
VOLUMETRIC: PROS AND CONS
• Motion parallax
• No accommocation / convergence rivalry
 Image transparency.
 Difficult capture for video
 Non-Lambertian distribution difficult
 Swept volume not suitable for TV
as this needs ‘window’ presentation
MULTIPLE IMAGE DISPLAYS
In multiple image displays, two or more images
are seen across the width of the viewing field.
 HOLOFORM: Large number of views give smooth
motion parallax and hence hologram-like appearance.
 MULTI-VIEW: Series of discrete views presented across
viewing field – these give motion parallax over limited
region.
 BINOCULAR: Two views only presented. These may
occupy fixed positions or follow viewers’ eye positions
using head tracking.
HOLOFORM
Holoform displays present
continuous motion parallax
across the viewing field
•
Motion parallax
 Large amounts of information
must be displayed
 Large image capture camera
QinetiQ
Cambridge
Holografika
Multi-view Displays
In multi-view displays, a series of discrete
views are presented across the viewing field.
VIEWING
ZONES
LENTICULAR
SCREEN
PARALLAX
BARRIER
Philips Multiview Display
X Y
1
3
2
1
5
4
7
6
3
2
2
4
6
1
3
5
7
5
7
2
4
6
4
6
1
3
5
X Y
7
A display that is so real you can
almost touch the objects as they
come out of the screen in 3D has
been a dream for many years.
But no longer claims Philips
technology which is combining
LCD manufacture, optical screen
design and image processing
software to deliver second
generation
3D
consumer
technology.
Multi-view – Pros and Cons
• Simple construction
• Philips is 3D/2D switchable
 Viewing area rather limited for TV use
 Reduced resolution –
but only factor of 3 in each direction
for Philips display and factor of 2 for
Sanyo 4-view.
BINOCULAR DISPLAYS
Binocular, or two-image, displays may be one of
three basic types:
• SINGLE VIEWER, FIXED VIEWING ZONES: Allows
only small viewer head movement - < 65mm laterally.
• SINGLE VIEWER, HEADTRACKED: Enables greater
freedom of head movement
• MULTI-VIEWER, HEAD TRACKED: The same pair of
images are presented to every viewer and large
freedom of movement enabled.
Fixed Viewing Zones
RIGHT LEFT
RIGHT
LEFT
Sharp 2D/3D Parallax
Barrier Display
Lenticular
RealityVision HOE Display
SeeReal Prism
Mask Display
Binocular:
Single Viewer, Head Tracked
• PRISM MASK: SeeReal have produced
a head-tracked version.
• HOE: A head-tracked RealityVision
display is probably being developed by
Samsung, but no definite information is
available about this.
• LENTICULAR (i) : Heinrich-HertzInstitut have produced display that
enables lateral head movement.
• LENTICULAR (ii) : Heinrich-Hertz-
Institut display developed to also allow
for Z-direction.
SeeReal Head Tracked Display
Binocular:
Multi-user, Head Tracked
Single user methods cannot be developed into
multi-user displays.




STEREO IMAGE PAIR ON ONE LCD SCREEN
EXIT PUPILS FORMED IN VIEWING FIELD
EXIT PUPIL PAIR FOR EACH VIEWER
PUPILS FOLLOW VIEWERS EYES BY HEAD TRACKING
FIRST PROTOTYPE
 TWO-YEAR €6M PROJECT LED BY PHILIPS
 DMU CARRIED OUT MULTI-USER DISPLAY
WORK
 ATTEST FINISHED IN MARCH 2004
 PROOF-OF-PRINCIPLE PROTOTYPE
DEVELOPED UNDER ATTEST
Exit Pupils
A
SCREEN
B
MULTIPLE EXIT
PUPILS
TOP VIEWS
R
VIEWER
L
EXIT PUPIL PAIR
C
STEERING ARRAY
 REPLACES CONVENTIONAL BACKLIGHT
 ARRAY EFFECTIVELY SERIES OF LENSES AND
LIGHT SOURCES
 SPACING DETERMINES DISTANCE
 PROVIDES 2-DIMENSIONAL CONTROL
Illumination
sources
Illumination
sources
Steering array
lenses
Steering array
lenses
Exit pupil
Exit pupil
STEERING ARRAY ELEMENT
LED array
Driver
board
Aperture
Coaxial optical element has no
off-axis aberrations.
Light contained within element
by total internal reflection.
To
viewer
IMAGE MULTIPLEXING




LCDs TOO SLOW FOR TEMPORAL MUX
LEFT AND RIGHT IMAGES ON ALTERNATE
LINES
HIGH RESOLUTION LCD (1200 X 1600)
MUX SCREEN BEHIND LCD
Steering
arrays
LCD
L
R
MUX
screen
To exit
pupils
Left exit
pupil
Right exit
pupil
Demonstrator Array
VIEWER B
VIEWER A
DEMONSTRATOR TARGETS
Viewer positions determined by
Polhemus 4-target head tracker
Prototype
STEERING
ARRAY
FOLDING
MIRROR
SCREEN
ASSY.
FIRST PROTOTYPE RESULTS –
ISSUES TO BE ADDRESSED:
 BRIGHTNESS
 BANDING
 CROSSTALK
BRIGHTNESS
 ARRAY USES LOW DENSITY 3mm LEDs
(ORIGINALLY MADE FOR DEMONSTRATOR)
LED DRIVERS
90 x 3mm WHITE LEDs
LIGHT
BANDING
CIE chromaticity diagram
Illuminating surfaces
0.5
Apertures
Light to
screen
Refracting surfaces
Y
(a) Array element configuration (top view)
0
(b) Appearance of aperture images
0
0.5
X
Figure 4. White LED colour variation
Relative
intensity
Distance across array
(c) Intensity variation
LCD DIFFRACTION
100
INTENSITY
RELATIVE
Relative
Intensity %(%)
3 COMPONENTS:
270 µM PIXEL PITCH
90 µM SUB-PIXEL PITCH
15 µM MICROSTRUCTURE
90
80
70
60
50
40
30
20
10
0
0
50
100
150
200
Distance(mm)
/ mm
DISTANCE
POINT SPREAD FUNCTION
NEC LCD SUB-PIXEL
MICROSTRUCTURE
250
FIRST PROTOTYPE
• USES 1800 x 3mm WHITE LEDs
• PERFORMANCE RELATIVELY POOR, BUT
•
•
SUFFICIENT FOR PROOF OF PRINCIPLE
EXIT PUPILS MOVE IN ~ 30 mm
INCREMENTS
EXPERIENCE GAINED USED FOR SECOND
PROTOTYPE
SECOND PROTOTYPE

CURRENTLY UNDER CONSTRUCTION

5120 WHITE SURFACE-MOUNT LEDs

I6-ELEMENT LED ARRAYS WITH LENSING

EXIT PUPILS MOVE IN ~ 10 mm INCREMENTS

GLASS OPTICAL ELEMENTS – LESS SCATTER

ANTICIPATE IMAGE WILL STILL BE DIM

CROSSTALK REDUCED BY:
OPERATING LCD IN PORTRAIT ORIENTATION
USING MORE SUITABLE LCD
DRIVER
CHIP
HEAT
SINK
MICROLENS
ARRAY
WHITE LED
& LENS
ARRAY
LIGHT
LIGHT
HEAT
SINK
DRIVER
CHIP
DRIVERS
16-element LED
Array Module
SCATTERING REDUCED
AT APERTURE AND
LENS SURFACE
FUTURE RESEARCH
FOLDING



•
•
•
•
WILL REDUCE SIZE TO CURRENT LARGER REAR PROJECTED SETS
WON’T BE SIZE OF SLIMMER REAR PROJECTED SETS AS FACETED
COMPONENTS CAN’T BE USED
DIFFICULT CONSTRUCTION:
SURFACE-SILVERED
HIGH ACCURACY
VISIBILITY OF CORNERS
CONSUMERS WILL DEMAND HANG-ON-WALL – FOLDING NOT SUFFICIENT
DIFFERENT CONFIGURATION NEEDED
LEDs MAY NOT MOST SUITABLE SOURCE:
Brightness variation
Colour variation
Insufficient light output
Large number of units
COULD USE ARRAY OF BLUE JUNCTIONS WITH COMMON PHOSPHOR
HANG-ON-WALL
Illumination Plane
TOP VIEW
SEMI-COAXIAL ARRAY



ARRAY ELEMENT
FLAT ILLUMINATION PLANE
ACYLINDRICAL LENS SURFACE
LARGE NUMBER OF INEXPENSIVE
MOULDED ELEMENTS
HANG-ON-WALL CONFIGURATION
 SLMs CAN BE USED (TRIED MONOCHROME LCD BUT
TOO DIM)
 POSSIBLY USE SLM IN FOURIER TRANSFORM PLANE
OF OPTICS FOR GREATER EFFICIENCY
 LIGHT COULD BE PIPED OR PROJECTED
SCREEN
ASSY.
 EVERY ILLUMINATION PLANE HAS SAME INFORMATION
VIEWERS
MIRRORS
STREERING
ARRAYS
ILLUMINATION
PLANES
TEMPORAL MUX –
(IF FAST LCD NOT AVAILABLE)
Static
Multiplexing
LEFT
STATIC
MUX
SCREEN
RIGHT
LCD
VIRTUAL
ARRAY
TEMPORAL
MUX SCREEN
REAL
ARRAY
Temporal Multiplexing
LCD
2-image Head-tracked Stereo:
Advantages
• Minimum amount of information
displayed.
• Smallest extra bandwidth required for
transmission ~ 10 - 15% (exploits
redundancy in stereo pair).
• Simplest image capture – could be
single camera pair (but might be better
to have an array to enable processing).
2-image Stereo:
Limitations
A
A
NO MOTION PARALLAX
IMAGE GEOMETRY DISTORTIONS
B
B
FALSE ROTATION
EYES
CONVERGE
ON ‘OBJECT’
EYES FOCUS
ON PLANE
OF SCREEN
R
L
FOCUS / ACCOMMODATION RIVALRY
DMU’S APPROACH


AIMED AT TV MARKET:
i.e. SEVERAL VIEWERS OVER ROOM-SIZED AREA
NOT SINGLE-VIEWER OR THEATRE
PRESENT STEREO PAIR ONLY:
NO MOTION PARALLAX BUT LEAST AMOUNT OF INFORMATION DISPLAYED
IMAGES PLACED IN VIEWING FIELD ONLY AT EYE LOCATIONS
SIMPLEST CAPTURE AND TRANSMISSION
HOWEVER, APPROACHES OTHER THAN TWOIMAGE HEAD TRACKED DISPLAYS MIGHT BE
APPROPRIATE, FOR EXAMPLE:
• MULTI-VIEW, AS CAN BE VERY SIMPLE TO IMPLEMENT
• HOLOFORM, WHERE REDUNDANCY IN IMAGE IS
EXPLOITED
•VOLUMETRIC WHERE IMAGE IS OPAQUE
THESE TECHNIQUES WILL BE
EXPLORED WITHIN THE 3D TV
NETWORK OF EXCELLENCE
3D TV NETWORK OF EXCELLENCE





EU FUNDED CONSORTIUM IN FRAMEWORK 6 OF IST PROGRAMME
4-YEAR PROJECT STARTED IN SEPTEMBER 2004
150 RESEARCHERS FROM 19 ORGANISATIONS
LED BY BILKENT UNIVERSITY
HAS STRONG ACADEMIC BIAS
WORK IS COVERED WITHIN 5 TECHNICAL COMMITTEES:
•
•
•
•
•
TC1: 3D SCENE CAPTURE AND SCENE REPRESENTATION
TC2: 3D TV CODING AND OTHER GENERIC ISSUES
TC3: TRANSMISSION
TC4: SIGNAL PROCESSING ISSUES IN 3D TV
TC5: 3D TV DISPLAY TECHNIQUES
3D TELEVISION SPECIFIC SUPPORT ACTION (TESSA)
‘Specific support actions are intended to support the
implementation of FP6, and may also be used to help
prepare for future Community research policy activities.’






WILL COVER ALL ASPECTS OF 3D (NOT JUST TV)
ROADMAPPING WITH QUESTIONNAIRES AND DELPHI ANALYSIS
CONTACT BETWEEN NETWORKS
COMPLEMENT ADRIA DISPLAYS NETWORK AND NoE
WILL HAVE INFLUENTIAL STEERING GROUP – LOT OF INTEREST
CURRENTLY UNDER EVALUATION - RESUBMIT SEPTEMBER IF UNSUCCESSFUL
LE CLUB
VISU
(FRANCE)
SID UK
CHAPTER
ASIA PACIFIC
TECHNOLOGY
NETWORK
3D CONSORTIUM
(INTERNATIONAL)
3D TV
NETWORK OF
EXCELLENCE
DMU
ADRIA
DISPLAYS
NETWORK
SID RUSSIA
& BELARUS
CHAPTERS
PHOTONICS
CLUSTER (UK)
DMU AT HUB OF 3D NETWORKING
CONCLUSIONS
 THE INTENTION IS FOR 3D TV TO COME TO
MARKET WITHIN THE NEXT TEN YEARS.
 TIMING IS RIGHT AS LCD AND OTHER ENABLING
TECHNOLOGIES ARE RAPIDLY EVOLVING.
 TWO-IMAGE HEAD TRACKING PARTICULARLY
SUITED FOR 3D TV, BUT OTHER METHODS TO BE
CONSIDERED ALSO.