Fulldome Display Specifications: A Proposal

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Fulldome Display Specifications A Proposal
Fulldome Standards SummitLHemisphericCIUDAD DE
LAS ARTES Y LAS CIENCIASValencia, SpainJuly
7-8, 2004

• Ed Lantz
• President
• Visual Bandwidth, Inc.
• ed_at_visualbandwidth.com

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Fulldome Systems
Single Projector(Fisheye)
Multi-Projector Edge-Blended
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Edge-Blended Projection
Polar Source is Split Into Sub-Frames and
Edge-Blended
Sub Frame 1 Sub Frame 2 Sub Frame 3 Sub
Frame 4
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Many Projection Configurations
Five Projectors Six Projectors
Seven Projectors
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Plethora of Projector Technologies

• DLP - Digital Light Processor
• LCoS - Liquid Crystal on Silicon
• CRT - Cathode Ray Tube
• Scanned Laser
• GLV - Grating Light Valve

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IPS Display Specification Standard Goals

• First-cut specifications for displays only
• Should expand to include image generator specs
• Ultimate spec must be a collaborative effort
• Independent of screen diameter reflectivity
• Should be similar to shopping for video projector
• System level specifications
• Were interested in what would be measured on
  dome, not individual projector performance

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Brightness Measurements
Display Brightness (fL) Screen Reflectance
Light Output (lumens)/Screen Area (sq. ft.)
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Brightness/Color Uniformity Measurements
Bpp () (Bmax Bmin)/Bavg 100
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Blend Uniformity Measurement
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Color Uniformity
1931 CIE x,y Chromaticity Diagram Courtesy
LEDtronics, Inc.
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Color Uniformity and delta E
MacAdam ellipses shown on the CIE 1931 (x,y)
chromaticity diagram at 10x magnification Wyszec
ki 1982
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Color Uniformity - conclusion
Do we want to ask our industry to purchase and
utilize spectrophotometers? Perhaps not. For
now we can be assured of first-order color
uniformity by requiring Color Uniformity and
Blend Uniformity specifications to hold for all
three primary colors in addition to white. This
technique makes the assumption that the RGB
primaries on all projectors are well matched at
the factory.
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Resolution
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Resolution
50 MTF Requirement for Defining CRT Resolution
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Contrast Ratio
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Instantaneous Contrast (IPS Test Pattern)
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Color Gamut
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Frame Rate
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Gamma
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References Wyszecki 1982 G. Wyszecki W.S.
Stiles, Color Science Concepts and Methods,
Quantitative Data and Formulae, John Wiley
Sons, New York, 1982 Halsted 1993 Charles P.
Halsted, Brightness, Luminance, and Confusion,
Society for Information Display, March 1993,
http//www.crompton.com/wa3dsp/light/lumin.html
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SIGGRAPH 2005  Fulldome Venue
In Planning
Los Angeles Convention Center
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Please review this spec and provide your feedback
for our proceedings!Thank you.
Ed Lantz President Visual Bandwidth,
Inc. ed_at_visualbandwidth.com