Operator`s manual

5-5
These are cosmetic blemishes in the image intensifier or dirt
or debris between the lenses. Black spots are acceptable as
long as they do not interfere with viewing the image. No action
is required if this condition is present unless the spots
interfere with the usability of the device.
4. Fixed-Pattern Noise.
This is usually a cosmetic blemish characterized by a faint
hexagonal (honeycomb) pattern throughout the viewing area
that most often occurs at high light levels or when viewing

every image intensifier if the light level is high enough. This
condition is acceptable as long as the pattern does not
inter f e r e wit h vie wing the image a nd u s a b ili t y of t h e device.
Figure 5 -4
Fixed-Pattern Noise
5. Chicken Wire.
An irregular pattern of dark thin lines in the field of view either
throughout the image area or in parts of the image area

form hexagonal or square-wave shaped lines. This is typically
viewed in high light conditions. No action is required if this
condition is present unless it interferes with the viewing
the image and interferes with the users usability of the
device.