1. A PROTOTYPE MULTI-VIEWER 3D TV DISPLAY
Phil Surman, Ian Sexton,
Richard Bates, Wing Kai Lee
IMAGING AND DISPLAYS RESEARCH GROUP
DE MONTFORT UNIVERSITY, LEICESTER, UK

2. 3D TELEVISION REQUIREMENTS
No Glasses (autostereoscopic)
Must support multiple viewers
Large viewing area
Compact housing size
Utilise readily-available technology
Low(ish cost)

3. 3D DISPLAY TAXONOMY Autostereoscopic Holographic Multiple Image
Volumetric
Real
Image
Holoform
Multi-
view
Binocular
Virtual
Fixed
Viewing
Zones
Head
Tracking
3D DISPLAY
TAXONOMY

4. 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).

5. HOLOGRAPHY QinetiQ MIT OASLM EASLM Output lens Horizontal Vertical
scanner
Vertical
scanner
AOM
Vertical
diffuser
Imaging
lens
QinetiQ
EASLM
OASLM
MIT

6. 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

7. 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

8. VOLUMETRIC
Virtual Image
Swept Volume
Static Volume

9. 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

10. 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.

11. HOLOFORM Holoform displays present continuous motion parallax
across the viewing field
QinetiQ
Motion parallax
Large amounts of information must be displayed
Large image capture camera
Cambridge
Holografika

12. Multi-view Displays
In multi-view displays, a series of discrete views are presented across the viewing field.
VIEWING
ZONES
PARALLAX
BARRIER
LENTICULAR
SCREEN

13. Philips Multiview Display
X Y
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.

14. 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.

15. 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.

16. Sharp 2D/3D Parallax Barrier Display SeeReal Prism Mask Display
Fixed Viewing Zones
Sharp 2D/3D Parallax Barrier Display
LEFT
RIGHT
Lenticular
SeeReal Prism Mask Display
RealityVision HOE Display

17. SeeReal Head Tracked 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-Hertz- Institut 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

18. Multi-user, Head Tracked
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

19. 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

20. Exit Pupils MULTIPLE EXIT PUPILS EXIT PUPIL PAIR TOP VIEWS A SCREEN B
VIEWER
EXIT PUPIL PAIR L R
TOP VIEWS

21. STEERING ARRAY REPLACES CONVENTIONAL BACKLIGHT
ARRAY EFFECTIVELY SERIES OF LENSES AND LIGHT SOURCES
SPACING DETERMINES DISTANCE
PROVIDES 2-DIMENSIONAL CONTROL
Exit pupil
Illumination
sources
Steering array lenses
Exit pupil
Illumination
sources
Steering array lenses

22. STEERING ARRAY ELEMENTTo
viewer
Aperture
Driver
board
LED array
Coaxial optical element has no off-axis aberrations.
Light contained within element by total internal reflection.

23. 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
MUX
screen
Steering
arrays
To exit
pupils R L
Left exit pupil
Right exit pupil
LCD

24. Demonstrator Array

25. VIEWER B VIEWER A DEMONSTRATOR TARGETS Viewer positions determined by
Polhemus 4-target head tracker

26. Prototype
STEERING
ARRAY
FOLDING
MIRROR
SCREEN
ASSY.

27. FIRST PROTOTYPE RESULTS – ISSUES TO BE ADDRESSED:
BRIGHTNESS
BANDING
CROSSTALK

28. BRIGHTNESS ARRAY USES LOW DENSITY 3mm LEDs
(ORIGINALLY MADE FOR DEMONSTRATOR)
90 x 3mm WHITE LEDs
LED DRIVERS
LIGHT

29. BANDING CIE chromaticity diagram 0.5 YX
CIE chromaticity diagram
0.5 Y
Figure 4. White LED colour variation
Apertures
Illuminating surfaces
Refracting surfaces
Light to
screen
(a) Array element configuration (top view)
(b) Appearance of aperture images
(c) Intensity variation
Distance across array
Relative
intensity

30. RELATIVE INTENSITY (%)
LCD DIFFRACTION
DISTANCE (mm)
RELATIVE INTENSITY (%)
3 COMPONENTS:
270 µM PIXEL PITCH
90 µM SUB-PIXEL PITCH
15 µM MICROSTRUCTURE
POINT SPREAD FUNCTION
NEC LCD SUB-PIXEL
MICROSTRUCTURE

31. 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

32. 16-element LED Array Module
SECOND PROTOTYPE
16-element LED Array Module
WHITE LED
& LENS ARRAY
DRIVER CHIP
HEAT SINK
LIGHT
MICROLENS ARRAY
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
DRIVERS
SCATTERING REDUCED
AT APERTURE AND
LENS SURFACE

33. 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

34. HANG-ON-WALL SEMI-COAXIAL ARRAY ARRAY ELEMENT Bottom layer Top layer
Apertures
Refracting
surfaces
Light to
LCD
Illumination Plane
TOP VIEW
SEMI-COAXIAL ARRAY
FLAT ILLUMINATION PLANE
ACYLINDRICAL LENS SURFACE
LARGE NUMBER OF INEXPENSIVE MOULDED ELEMENTS
ARRAY ELEMENT

35. HANG-ON-WALL CONFIGURATION
SCREEN
ASSY.
STREERING
ARRAYS
MIRRORS
ILLUMINATION
PLANES
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
EVERY ILLUMINATION PLANE HAS SAME INFORMATION
VIEWERS

36. Temporal Multiplexing
TEMPORAL MUX –
(IF FAST LCD NOT AVAILABLE)
LEFT
RIGHT
STATIC MUX
SCREEN
LCD
Static Multiplexing
REAL
ARRAY
VIRTUAL ARRAY
TEMPORAL
MUX SCREEN
LCD
Temporal Multiplexing

37. 2-image Head-tracked Stereo: Advantages
Minimum amount of information displayed.
Smallest extra bandwidth required for transmission ~ % (exploits redundancy in stereo pair).
Simplest image capture – could be single camera pair (but might be better to have an array to enable processing).

38. FOCUS / ACCOMMODATION RIVALRY
2-image Stereo:
Limitations A B
NO MOTION PARALLAX
IMAGE GEOMETRY DISTORTIONS
FALSE ROTATION
EYES FOCUS
ON PLANE
OF SCREEN
EYES CONVERGE
ON ‘OBJECT’ L R
FOCUS / ACCOMMODATION RIVALRY

39. DMU’S APPROACH AIMED AT TV MARKET: PRESENT STEREO PAIR ONLY:
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 TWO-IMAGE 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

40. 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

41. 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
DMU
3D CONSORTIUM
(INTERNATIONAL)
SID RUSSIA
& BELARUS
CHAPTERS
ASIA PACIFIC
TECHNOLOGY
NETWORK
PHOTONICS
CLUSTER (UK)
ADRIA
DISPLAYS
SID UK
CHAPTER
LE CLUB
VISU
(FRANCE)
3D TV
NETWORK OF
EXCELLENCE
DMU AT HUB OF 3D NETWORKING

42. 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.