3M
Overhead Projector 9800 Series
Section 3 – Maintenance
3-1
9800 Service Manual
3M 1996
3-1.
Cleaning
For best performance, the optical surfaces of a
projector must be free of excess dust and surface dirt.
Procedures for cleaning the following optical surfaces
are covered in this section:
•
Projection Mirror
•
Projection Head Lens
•
Magnifier Lens
•
Stage Glass
•
Fresnel Lens
Note
Use 3M
Overhead Cleaner 676 (Figure 3-1)
to remove surface dirt from the stage glass
and projector lens.
Figure 3-1. 3M
Overhead Cleaner 676
3-1-1. Projection Mirror
1. To remove surface dirt, use a soft brush or
compressed air. Figure 3-2.
2. To remove smudges or fingerprints, dampen a
cotton ball or soft, lint-free cloth with 3M
overhead cleaner and gently rub mirror surface.
Figure 3-3.
Caution
!
The projection mirror is a front surface mirror.
Hard rubbing will damage the mirror surface.
9800–54I
Figure 3-2. Removing Surface Dirt
9800–55I
Figure 3-3. Removing Smudges or Fingerprints