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Appendix C
DMD Image Quality
1. SCOPE
This document specifies the image quality requirements applicable to the DLP
TM
XGA Component Set.
The Component Set provides the DLP
TM
XGA Projector with digital imaging functionality based on
Digital Micromirror Device (DMD) technology.
2. Definitions
2.1 Blemish
A blemish is an obstruction, reflection, or refraction of light that is visible, but out of focus in
the projected image under specified conditions of inspection (see Table 1). It is caused by a
particle, scratch, or other artifact located in the image illumination path.
2.2 Dark pixel
A single pixel or mirror that is stuck in the OFF position and is visibly darker than the
surrounding pixels.
2.3 Bright pixel
A single pixel or mirror that is stuck in the ON position and is visibly brighter than the
surrounding pixels.
2.4 Unstable pixel
A single pixel or mirror that does not operate in sequence with parameters loaded into
memory. The unstable pixel appears to be flickering asynchronously with the image.
2.5 Adjacent pixel
Two or more stuck pixels sharing a common border or common point, also referred to as a
cluster.
2.6 Streaks
Artifact resulting from locallized variation in mirror tilt angle relative to surrounding mirrors.
They are similar in appearance to window scratches but appear at the mirror level. Streaks
appear as faint diagonal or arcing patterns in the image.
2.7
Sea of Mirrors (SOM)
SOM is a rectangular array of off-state mirrors surrounding the active area.
2.8 Eyecatcher
A small localized light “spot” which has high spatial frequency and high differential
brightness. These are due to various DMD window or window aperture “defects” including:
digs, voids, particles and scratches.
2.9 Border
Artifacts
All variations of these artifacts are acceptable under this image quality specification.
Border artifacts are a general category of image artifacts that may show up on screen in the
area outside of the active array. Border artifacts include: Exposed Bond Wires, Exposed
Metal 2, and Reflective Edge.
10
Summary of Contents for PB8220 - XGA DLP Projector
Page 14: ...Figure 1 Major Blemish Two Zone Screen Critical Zone center 25 Non Critical Zone 13 ...
Page 33: ...Installation 15 User s Guide 4 Video device or VCR 5 Output monitor ...
Page 49: ...42 ...
Page 50: ...43 ...
Page 51: ...8 Lamp Replacement 44 ...
Page 52: ...45 ...
Page 53: ...46 ...
Page 54: ...9 Shutdown 47 ...
Page 89: ...Chapter 6 Trouble Shooting 82 ...
Page 90: ...83 ...
Page 98: ...6 DMD Board Trouble Shooting Guide 91 ...
Page 99: ...92 ...
Page 100: ...Chapter 7 Schematics and Assy Drawing 93 ...
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Page 105: ...Form No ACM0 0B 003 24 010918 ...
Page 106: ...Form No ACM0 0B 003 24 010918 ...
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