Know-How

How to setup a 3D stereo projection?

Possible 3D-projector setups

Setup	Supported Projectors	Available products	Required Glasses
Single standard projector + shutterglasses	Film, CRT, (DLP, LCD limited)	Certain standard projectors, Sensio3D	Shutter
Single standard projector + active polariziation-shutter-plate	Film, CRT, (DLP, LCD limited)	3DTV	Polarizer
Single 3D-LCD-projector with line-sequential polarization	special 3D-LCD projector	VRex	Polarizer
Single 3D-DLP-projector	special 3D-DLP projectors	Barco, VRex, ChristieDigital, InFocus/Lightspeed	Shutter
Dual LCD-projectors with internal polarizing	special pre-polarized LCD projectors	Barco	Polarizer
Dual standard projectors plus polarizing filters	Film, CRT, DLP, certain LCD	Cyviz, digital image, more3d, 3DTV, APEC, VRex, ImageTek and several more	Polarizer
Dual standard projectors plus INFITEC processor and filters	Film, CRT, DLP, LCD	more3d	INFITEC
Dual standard LCD-projectors plus polarizing filters and switched green components (StereoBrightTM-method)	current standard LCD projectors	Advisol	Polarizer
Dual standard projectors plus shutterglasses	Film, DLP (special synchronization required)	Sony IMAX3D, digital image	Shutter

Abbreviations:
CRT: cathode ray tube, such projectors have 3 tubes
DLP: Digital light processing by Texas Instruments, utilizes MMD - micro mirror device chips; already used for digital screenings in selected movie-theatres
Laser: projection through ultra hi-speed Laser modulation and deflection, developed by german Schneider and Daimler-Chrysler corporations, prototypes available, extremely expensive. Someday this may become the dominating projector-technology. I expect them to make an excellent team with shutterglasses. Projects on any uneven surface with perfect focus. Would be perfect for CAVE-like VR projects.
LCD: liquid crystal display - very common in projectors nowadays
Notes:
- The polarizer setups require a special projection-screen which retains the polarization (non-depolarizing-screen)
- Barco offers short-persistence CRT-projectors to fight ghosting
- DLP projectors usually support low refresh rates only which causes problems with Shutterglasses and Shutter-Plates setups
- The best, i.e. ghost-free, results should be obtained with Film, DLP or Laser projectors and shutterglasses

Video/VGA-signal sources:
- to use a multiplexed frame-sequential 3D-signal (3D-VHS, Nu-View, ELSA Revelator, etc.) on a dual-projector setup you’ll need a de-multiplexer (signal splitter)
- to use two genlocked video-streams on a single projector setup you’ll need a multiplexer (signal mixer)

3D-Projection Systems
single-standard-projector setups

Single CRT-projectors & 3D-shutterglasses

CRT (cathode ray tube) projectors usually work right away with PC- and TV-shutterglasses. Digital buffers/line-doublers in the projector must be disabled though. CRT-projectors may produce heavy ghosting and the frequency range may be limited, resulting in low-resolution and/or low refresh rates.

Standard projectors suitable for active stereo3D with shutterglasses in a single-projector setup
Projector model	60 Hz VGA with PC-shutterglasses	60 Hz NTSC 3D-video with TV-shutterglasses	50 Hz PAL 3D-video with TV-shutterglasses	Comments
A+K AstroBeam X20 ASK M2 Boxlight XD-2m Dukane ImagePro 8746 InFocus LP70 Proxima DP1000x Toshiba TDP-P5-US	Doesn’t work Sync between VGA and proj. unstable, moving time-gap, tearing effects. PC-shutterglasses out of sync 99% of the time.	Works Some red ghosting in scenes which contain red. This means green, blue and white segments of color wheel are in sync with shutterglasses, red segment is not fully in sync.	Works Some red ghosting in scenes which contain red. This means green, blue and white segments of color wheel are in sync with shutterglasses, red segment is not fully in sync.	Tested by Christoph Bungert on Infocus LP70 with i-O Display and 3DTV controllers. Other projector models listed are identical. DVI-connection destroys 3D-information. Other VGA-frequencies don’t work.
InFocus LP650 InFocus X1 InFocus X2	Works			requires glasses to be in reverse, since there’s a 1-frame delay, some reports of getting X2 working with 75Hz.

3DTV Stereo Plate polarization panel for 3-tube-CRT projectors (active, field sequential)

SENSIO 3D is a 3D video processor which works for most standard LCD & DLP-projectors Sensio utilizes single standard projectors, specially formatted 3D-DVD’s and 3D-shutterglasses.

single-projector 3D setups

BARCO

BARCO has an excellent page about stereoscopic 3D projection covering shutterglasses, shutter-z-screens, polarization glasses, single and dual projector setups with CRT, LCD and DLP. BARCO offers special ‘fast green phosphor’ versions of some of it’s 3-tube-projectors to reduce ghosting.

Barco offers a color brochure on stereo projection. Also available in Acrobat Format!

BARCO Galaxy family DLP active stereo3D projectors

for shutterglasses

3.Chip DLP

110 Hz

4000-9000 ANSI lumens

SXGA+ resolution

Christie Mirage 10000 DLP active stereo3D projector

for shutterglasses

3.Chip DMD Optical System

10,000 ANSI lumens

XGA resolution

1900W Xenon illumination system

250:1 ANSI Contrast Ratio

Wide array of optional lenses

Christie Mirage 5000 DLP active stereo3D projector

for shutterglasses

5000 ANSI Lumens

SXGA resolution

SLIC(spatial light imaging construction)

3D Stereo Module

Christie Mirage 2000 DLP active stereo3D projector

for shutterglasses

3Chip DMD Optical System

2000 ANSI Lumens

SXGA resolution

SLIC? (spatial light imaging construction)

3D Stereo Module

InFocus/

Lightspeed Design Group.

(c).InFocus/Lightspeed Design Group DepthQ

Low-cost 1-chip-DLP single projector stereo3D solution

InFocus DepthQ? stereoscopic, distributed by Lightspeed Design Group. www.DepthQ.com

Main specifications:

DLP, 800x600, 100/120Hz (real fps), 2000:1 contrast, 1600 ANSI, page-flipping-stereo3d-support for almost all PC-VGA-shutterglasses, $3,495 (as of March 2005)

According to the official specifications the projector produces ‘one frame delay’. This means a stereo-reverse switch on the glasses or in the software is required.

The projector could also be interesting for other (2D) applications which require a high frame rate. I’m not aware of any other digitial display device which can show true 120 full-frames per second.

GALI-3D has been authorized by Lightspeed Design to resell the InFocus DepthQ(tm) projector as a nonexclusive dealer for sale in the Czech Republic and other locations in Europe. In addition GALI-3D has made available a discussion board related to this device.

VREX

VRex VR-1000 LCD overhead 3D-projection panel (micro-polarizer, line-sequential)

VRex VR-1100 LCD overhead 3D-projection panel, hires (micro-polarizer, line-sequential)

VRex VR-2000 LCD 3D-projector (micro-polarizer, line-sequential)

VRex VR-2020 LCD 3D-projector, hi-brightness (micro-polarizer, line-sequential)

VRex VR-3100 LCD 3D-projector, (micro-polarizer, line-sequential)

(Jan.2001): VRex VR-4200 XGA DLP 3D-projector for polar- and shutterglasses;

uses proprietary vertical line-sequential stereo format (so I assume it delivers only half-res per eye!),

VESA DIN-3 shutterglasses connector, 120 Hz

imagetek

imagetek Series 1000 projector (passive, line-sequential)

dual-projector 3D setups

CYVIZ offers dual-projector bundles with polarizers and their xpo-demultiplexer series

digital image moble Immersion Cube 3D

2 projectors and a VGA-demultiplexer in one handy box.

Passive (polarizer - linear or circular) and active (shutterglasses) versions available.

more3D morpheus3 mobile - INFITEC more3D morpheus3 mobile - POLARIZED

demultiplexers

for dual-projector 3D setups

In order to distribute a single 3D-content stream (for example a 3D-DVD-signal) to 2 projectors you’ll need some hardware- or software demultiplexer to make 2 streams out of 1.

VGA - Demultiplexers

The CYVIZ xpo.1 and xpo.2 are VGA-level demultiplexers which turn a single VGA page-flipping signal

into two VGA- or DVI-streams for two projectors or dual-input-HMDs.

The xpo.1 supports resolutions up to 1024x768, the xpo.2 goes up to 1280x1024.

digital image Split 3D
VGA-level demultiplexer by digital image which turns a single VGA page-flipping signal
into two VGA- or DVI-streams for two projectors or dual-input-HMDs.
1024x768 and 1280x1024 versions available, as well as custom-resolution versions
The latest software accepts stereo signals without synchronisation signal to connect to GeForce graphic boards on notebooks.

more3D - the software alternative to hardware VGA-demultiplexers:
professional universal stereo-driver for dual-VGA-output
more3D offers a universal driver which creates stereo3D from most Direct3D games or applications (OpenGL announced) and delivers two full-resolution VGA-signals from a dual-head nVidia VGA board. The signals can be used to drive dual-projector setups, dual-input HMD’s or dual-input autostereo-displays.
In other words you’ll save the money for an expensive VGA-demultiplexer and prevent all the instabilities which can happen with software page-flipping. The more3D driver can also be adapted for multi-channel-autostereo displays, such as 4D-Vision 4D, StereoGraphics SynthaGram or Philips 3D-LCD.
System requirements for a 3D-projection system: more3D, nVidia GeForce 4 Ti 4600 with dual-VGA-output, Intel P4 1.7GHz or better, Win2000 or WinXP, two identical projectors, polarizing filters, polarizing glasses, non-depolarizing silver screen.
more3D is based in Cologne, Germany and was founded in 2001 by a group of former ELSA stereo3D experts. more3D is for professionals only. According to a spokesman the new driver wasn’t derived from the Revelator or nVidia driver, but developed from scratch.

The nVidia reference stereo driver does support dual output, eliminating the need for a hardware demultiplexer.

Peter Wimmer’s Stereoscopic Player is freeware and can display 3D-DVD’s and other digital 3D-movie content via dual-output on a standard dual-head VGA-board.

Tags:projectors,3D,4d,digital image,dual-projector