BenQ PB8220 - XGA DLP Projector, Service Manual

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2.9.1 Bond Wires
Bond Wires attach the die to the superstructure. If visible, they will appear as short light
parallel lines outside of the Sea of Mirrors (SOM).
2.9.2 Exposed Metal 2
Exposed Metal 2 is due to a shift in positioning of either the die or the window aperture
which may allow light to be reflected off of the layer of metal 2 that is below the super
structure (mirrors). This defect is located at the outer edge of the SOM.
2.9.3 Reflective Edge
Reflective Edge is light that may reflect from the edge of the DMD’s window aperture onto
the projection screen. It will appear as a thin diffuse line outside of the SOM.
2.10 Two Zone Blue 60 Screen
The Two Zone Blue 60 screen is used to test for major dark blemishes. Refer to Figure 1 for
configuration. All areas of the screen are colored a Microsoft Paintbrush blue 60 (green and
red set at 0, blue set at 60).
NOTE: If linear degamma is not used then the Microsoft Paintbrush values must be adjusted
to match the degamma table being used in order to generate an equivalent blue level on the
test screen image.
2.11 Two Zone Gray 10 Screen
The Two Zone Gray 10 screen is used to test for major light blemishes. Refer to Figure 1 for
configuration. All areas of the screen are colored a Microsoft Paintbrush gray 10 (green, red,
and blue set at 10).
NOTE: If linear degamma is not used then the Microsoft Paintbrush values must be adjusted
to match the degamma table being used in order to generate an equivalent gray level on the
test screen image.
3. ACCEPTANCE REQUIREMENTS
3.1 Conditions of Acceptance
All DMD image quality defects must be determined under the following projected image
test conditions:
a.
Projector degamma shall be linear.
b. Projector error diffusion shall be “off.”
c. Projector brightness and contrast settings shall be set to nominal.
d. The diagonal size of the projected image shall be a minimum of 60
inches.
e.
The projection screen shall be 1X gain.
f. The projected image shall be inspected from an 8 feet minimum viewing
distance.
g.
The image shall be in focus during all Table 1 tests.
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