American Technologies Network ATN PS31, Руководство оператора

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FLASHING. This is a defect in the image area of the goggles. The
image appears to flicker or flash.
FLICKERING. See “flashing.”
GAIN. This is the number of times a night vision device amplifies
light input.
IMAGE INTENSIFIER. An electro-optical device that detects and
amplifies ambient light to produce a visual image.
INFINITY FOCUS. Adjustment of the objective lens so that a distant
object, such as a star or the point light on a distant tower, forms the
sharpest image.
INTERMITTENT OPERATION. This is a defect in the image area of
the goggles. See “flashing”.
IR SOURCE. This is an IR Light Emitting Diode (LED). When turned
on, the IR source provides additional illumination to enhance exist-
ing light conditions used only for performing nearby tasks.
MICROCHANNEL PLATE. A current-multiplying optical disk that
intensifies the electron image produced by the photocathode.
NOTE. Essential information of special importance, interest, or aid
in job performance.
PHOTOCATHODE. The input optic of an image intensifier that ab-
sorbs light energy and in turn releases electrical energy in the form
of an electron image.
SCINTILLATION. A faint, random, sparkling effect throughout the
image area. Scintillation is a normal characteristic of the image in-
tensifier and should not be confused with emission points. Scintil-
lation is more pronounced under low light conditions. Also called
“video noise”.
SHADING. The viewed image should be a full circle. If shading is
present, you will not see a fully circular image. Shading is indicative
of a dying photocathode and is caused by a defective vacuum seal
of the image intensifier. Shading is very dark and you cannot see
an image through it.
WARNING. Conditions, practices, or procedures that must be ob-
served to avoid personal injury or loss of life.
1.1.5. GLOSSARY
BLACK SPOTS. These are cosmetic blemishes in the image inten-
sifier of the NVG or dirt or debris between the lenses.
BRIGHT SPOTS. These defects can appear in the image area of
the NVG. This condition is caused by a flaw in the film on the micro-
channel plate. A bright spot is a small, nonuniform, bright area that
may flicker or appear constant. Bright spots usually go away when
the light is blocked out and are cosmetic blemishes that are signal
induced.
CAUTION. Condition, practices, or procedures that must be ob-
served to avoid damage to equipment, destruction of equipment, or
a long-term health hazard.
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. Under the worst case condition, these lines will form hexago-
nal or square-wave shaped lines.
DARK (OR DARK AREA). A place in which there is very little light.
It does not mean total darkness. Generally, this means conditions
similar to a quarter-moon or starlit night.
DARK-ADAPTED. Having ones eye adjusted to the goggles’s out-
put under low light conditions.
DIOPTER. A unit of measure used to define eye correction. Adjust-
ments to the diopter adjustment will provide a clearer image in each
eye.
EDGE GLOW. This is a defect in the image area of the goggles.
Edge glow is a bright area (sometimes sparkling) in the outer por-
tion of the viewing area.
EMISSION POINT. A steady or fluctuating pinpoint of bright light
in the image area and does not go away when all light is blocked
from the objective lens of the goggles. The position of an emis-
sion point within the image area of the goggles does not move. An
emission point should not be confused with a point light source in
the distance.
FIXED-PATTERN NOISE. This is a cosmetic blemish in the im-
age area characterized by a faint hexagonal (honeycomb) pattern
throughout the viewing area that most often occurs at high light
levels or when viewing very bright lights. Fixed-pattern noise is in-
herent in the structure of the fiber optics and can be seen in every
image intensifier if the light level is high enough.