Sharp XG-NV2SB, Service Manual

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20
XG-NV2SB
CONVERGENCE AND FOCUS ADJUSTMENT
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Start the convergence and focus adjustments with the top cabinet and the LCD covers
(Top/Bottom) removed but the power on. Use the remote control to adjust the image.
Take the following procedures.
1. Focusing the projection lens
(A) Replacing all the 3 LCD panels
1. Before replacing all the 3 LCD panels, project an image on the screen and bring it into focus.
2. Replace the panels with new ones. But until the focus has been completely readjusted, be careful not to
change the distance between the set and the screen, nor to move the projection lens focus and zoom
rings.
If the focus is readjusted with a different positional relation, the relation between the projection distance
and the screen size is affected. In other words, a short-distance image (40 WIDE, for example) may get
out of the focus range, or a long-distance image (300 WIDE, for example) may come out of focus.
(B) Replacing 1 or 2 of the 3 LCD panels
1. In adjusting the focus after replacement of one or two LCD panels, project an image on the screen and turn
the projection lens focus ring to get the non-replaced LCD panel into focus.
2. But until the focus has been completely adjusted for the new LCD panels, be careful not to change the
distance between the set and the screen, nor to move the projection lens focus and zoom rings.
(If the distance has been changed or the projection lens readjusted, repeat the above steps 1 and 2.)
2. Adjusting the G-LCD panel
(A) Focus adjustment. (Make this adjustment on the white-only screen.)
1. Right-and-left focus adjustment (
θ
Y direction) .
Loosen the lock screws "b" and "c" and insert the eccentric screwdriver into the notch and hole "b". Turn
the screwdriver until the right and left halves on the screen get into focus.
First get the right and left halves in balance. Then improve the accuracy while making the adjustment 2
below.
2. Top-center-bottom focus adjustment (
θ
X and Z directions).
Loosen the lock screws "a" and "c" and insert the eccentric screwdriver into the notch and hole "a" or "c".
Turn the screwdriver until the top, center and bottom on the screen get into focus. In adjusting this top-to-
bottom focus, temporarily tighten the lock screw "b" to fix the
θ
Y direction adjustment.
3. Repeat the above steps 1 and 2 to finely adjust the focus. Finally tighten up all the lock screws.
Notes :
1
Carefully proceed with the focus adjustment because the adjusting directions are correlated.
2
In adjusting the convergence and focus, do not move the projection lens zoom and focus rings until the end
of all the adjustments.
(B) Convergence adjustment
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The G-LCD panel has no convergence adjustment mechanism. Use this panel as convergence adjustment
reference.
3. B-LCD panel adjustment (the same for the R-LCD panel)
(A) Focus adjustment
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Take the same procedure as for the G-LCD panel focus adjustment. Note that the adjustment range is small
in the Z direction. If the convergence is quite different between the B-LCD and G-LCD panels, roughly adjust
the convergence first and then the focus.
(B) Convergence adjustment
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Use a crosshatch pattern signal for this adjustment.
Make the adjustment just for the G-color and the relevant color.
(1) Loosen the convergence lock screw "d".
(2) With the G-LCD panel’s screen center as reference, adjust the B-LCD panel in the X, Y and
θ
Z directions.
(3) Finally tighten up the convergence lock screw "d".