Specifications
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DESCRIPTION AND DATA
2.1 SYSTEM DESCRIPTION
The Sirius is a hand-held, head-mounted or helmet-mounted night vision system that allows the user
to operate it while walking, conducting short-range surveillance, reading maps, conducting vehicle
maintenance, or administering rst aid in both moonlight and starlight conditions.
The Sirius utilizes the principle of intensication of the residual light that is reected from the surround-
ing objects. The optical system of the unit consists of an objective lens, an intensier tube (IT), and an
eyepiece.
The Sirius automatic brightness adjustment system retains the same gain (image brightness), even un-
der unsteady light conditions.
The Sirius automatic protective system controls illumination through a photoreceiver. If the illumina-
tion level surpasses 100-300 lx for more than 10 s, the unit will shut o automatically.
A built-in IR illuminator makes it possible to use the unit in low light or total darkness.
The Sirius uses LED lights to indicate illumination level, low battery, and to show the user that the IR
illuminator is on.
TheSiriusallowsforverticalandfore-and-aftadjustmentwhenmountedtotheuser’sheadorhelmet,
when focusing the lens, and when focusing the eyepiece.
Additionally, the Sirius-M version incorporates gain control, which allows the user to increase or de-
crease the brightness of the image to compensate for overly bright or extremely dark conditions.
NOTE:
The equipment requires some light (moonlight, starlight, etc.) to operate. Performance of the
device depends upon the level of ambient light in the environment. Please remember the fol-
lowing:
— The level of ambient light in the environment is reduced by the presence of clouds, shade,
or objects that block natural light (trees, buildings, etc.
— The equipment is less eective when operated in shadows and other darkened areas.
— The equipment is less eective when operated in rain, fog, sleet, snow, or smoke.
— Under starlight conditions, particularly in low-contrast environments such as snow-cov-
ered territory, sandy deserts, large bodies of water or grassy hills, the visibility may degrade,
thereby disguising or masking changes in terrain.
— The equipment will not “see” through dense smoke.