Specifications

also be installed on the NM-108 BC top Weaver rail.
NOTE:
The NM-108 BC can also be installed in front of the viewfinders of various instruments to
widen the operational illumination range.
Chapter 2. DESCRIPTION AND DATA
2.1 System Description
The NM-108 BC consists of two primary parts, as shown in Figure 2-1: the night vision device
(hereafter referred to as NVD), and the quick release mount system, or mount. The NM-108 BC is
delivered already assembled: the mount (B) should be secured to the rail (A) of the NVD (D) with two
screws.
Figure 2-1. NM-108 BC NIGHT VISION CLIP ON SYSTEM
The optical-electronic system of the NVD includes four main components: the objective and output
lenses, an image intensifier tube, and the wired body (C).
The objective lens focuses available light (photons) on the photocathode of the image intensifier tube
(IIT). The light energy causes electrons to be released from the cathode. After being amplified, the
electron flow represents an intensified version of the original image of the scene. The electrons then
strike the IIT phosphor screen, which reacts to them by glow that is visible to the human eye. The im -
age is projected by the output lens from the IIT screen to infinity, and the resulting image is magnified
when viewed through the day scope. As such, when the NM-108 BC mounted in front of the day
scope, it converts the latter into a night vision sight.
The automatic brightness adjustment system maintains consistent image brightness, even in changing
light conditions. The manual gain control (optional feature) allows the operator to refine the image
contrast by compensating for overly bright or extremely dark conditions.
The bright light protection system controls the existing ambient light through a photoreceiver, and
D
B
A
B
C