3M
Multimedia Projector MP8620
Adjustments
3M 1999
1-8
Triplet lens
1-9.
Lamp Alignment
A poorly aligned lamp can reduce the brightness or the uniformity of the projection image. To ensure that the
projector is producing the best possible image lamp alignment should be checked regularly.
1-9-1.
Check the Lamp Alignment
1.
With the projector off, remove the lamp assembly using
the procedure listed in the Disassembly/Reassembly
section.
2.
Hold the lamp assembly and look through the condenser
at an angle perpendicular to the condenser lens.
3.
The lamp should be aligned using the reflection image on
the lamp reflector. The image of the lamp should be
slightly above or slightly below the lamp.
4.
If not, this position can be changed by turning
the two adjustment screws below the lamp
sockets.
5.
Verify the lamp alignment by powering up the
projector and viewing the image of the lamp on
the screen. This can be done by holding a triplet
lens in front of the projector lens .
6.
Visually check to make sure the image of the lamp arc is positioned correctly:
b . I m
a g e o f
h i d d
b y
l
c . I m
a g e
f
d
l a m
p a r c t o
f
Incorrect lamp
alignment:
Image of arc
hidden by lamp
Images of arcs
too far apart
Image of
arc
Correct lamp
alignment:
Image of
reflected
arc
Reflected image
of lamp slightly
below
