American Technologies Network ATN PS31, Руководство оператора

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To check for edge glow, block out all light by cupping a hand over
the objective lens. If the image intensifier is displaying edge glow
the bright area will still show up. Return the NVG to the maintainer.
EDGE
GLOW
FIGURE 2.4. EDGE GLOW
(3) Flashing, Flickering, or Intermittent Operation. The image may
appear to flicker or flash. If there is more than one flicker, check for
loose battery cap or weak battery. If weak or loose batteries are not
the problem return the NVG to the maintainer.
c. Cosmetic Blemishes
These are usually the result of manufacturing imperfections that do
not affect intensifier reliability and are not normally a cause for re-
jecting an NVG. However, some types of blemishes can get worse
over time and interfere with the ability to perform the mission. If you
believe a blemish is cause for rejection, record the specific nature
of the problem on the maintenance forms and identify the position
of the blemish by using the clock method and approximate distance
from the center (e.g., 5 o’clock toward the outside, 2:30 near the
center, or 1:00 midway). The following are cosmetic blemishes:
(1) Bright Spots. A bright spot is a small, nonuniform, bright area
that may flicker or appear constant (Figure 2.5.). Not all bright spots
make the NVG rejectable. Cup your hand over the objective lens to
block out all light. If the bright spot remains, return the NVG to the
maintainer. Bright spots usually go away when the light is blocked
out. Make sure any bright spot is not simply a bright area in the
There are two groups of “defects” you may encounter — opera-
tional defects and cosmetic blemishes. Operational defects are an
immediate cause to reject the NVG. Cosmetic blemishes are not
a cause for rejection unless they become severe enough to inter-
fere with the ability to perform the mission.
The rejection of any
NVG for cosmetic defects must be based on an outdoor evalu-
ation and not the TS-4348/UV Test Set.
b. Operational Defects
These defects relate to the reliability of the image intensifier and
are an indication of instability. If identified, they are an immediate
cause for rejecting the NVG. They include shading, edge glow,
flashing, flickering, and intermittent operation.
(1) Shading. If shading is present, you will not see a fully circular
image (see Figure 2.3.). Shading is very dark and you cannot see
an image through it. Shading always begins on the edge and mi-
grates inward eventually across the entire image area. Shading is
a high contrast area with a distinct line of demarcation. Return the
NVG to the maintainer.
SHADING
FIGURE 2.3. SHADING
NOTE
Make sure the shading is not the result of improper eye-relief
adjustment (refer to paragraph 2.4.2.).
(2) Edge Glow. Edge glow is a bright area (sometimes sparkling) in
the outer portion of the viewing area (see Figure 2.4.).