Optical Function.
The thermal collimator is used to provide a 58-inch focal length for
the night sight testing and alinement.
The thermal sight collimator radiates infrared energy from the
temperature controller assembly.
The energy is reflected from a
collimating mirror to present a collimated beam of infrared rays.
These rays can be viewed with the night sight being tested.
The target source is placed near the focal point of the collimating
mirror.
The target source provides images of target patterns to a
night sight.
The focal length of the collimating mirror is 58
inches. The infrared energy from the target source is reflected from
a folding mirror to the collimating mirror.
The folding mirror is
used to achieve the 58-inch focal length in a shorter actual length.
Each beam of visible light passes through a visible light window
where it may be viewed as a visible image.
Figure 3-11.
Optical Function.
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MM4812