Si protection window for a night-sight operating at 3-5um range
Generally used as a front window transmitting over the working range to protect an optical assembling of IR night vision system. Detection range is 10km.
In combination with a window for a visible channel (for a daylight inspection-see below # 2) such night-sights are placed at some military-oriented vehicles.
Overall dimensions, mm
218.0 (-0.3 / -0.5) x 119.0 (-0.3 / -0.5)
16 (+/- 0.2)
Surface quality, scr / dig
Surface figure, fringes
N <= 5, deltaN <= 0.3 @ 633 nm
Wedge, arc. Min.
AR Coating (DLC / DLC type) @ 3-5 um
See the curve attached