1-20. SYSTEM FUNCTIONAL DESCRIPTION (cont)
(f) The dayside sensor mount assembly supports and positions the TADS
dayside sensor assembly for testing.
The UUT is locked in place by use of the sensor
mount handle, which contains two optical switch assemblies that sense the lock and
The dayside sensor mount assembly contains the following
Laser interface assembly
Laser safety shield assembly
(g) The laser interface assembly supports the laser spot tracker and laser
range receiver UUTS for testing.
A handle on the left side is turned to move the
laser interface assembly right (carriage in) or left (carriage out). Two optical
switches sense the carriage in and carriage out positions.
(h) The laser attenuator is located on the front of the laser interface
It consists of an attenuator lens which is moved in and out of the optic
path by a lever (attenuator handle).
Two optical switches sense the attenuator in and
attenuator out positions.
(i) The laser safety shield assembly is located between the laser interface
assembly and the shutter assembly.
The shield has a handle on the left side which is
used to move the shield to the right (closed) and to the left (open). Before the
shield can be opened, the laser interlock handle must be moved to the down position
After the shield is closed the laser interlock handle is moved up to
This actuates the interlock actuator switch (part of the laser interlock
circuit) and also mechanically locks the UUT mounting adapter, located inside the
laser cover assembly.
Two optical switches sense the shield open and shield closed
(j) The laser fold mirror assembly consists of a two-position translator
with a single fold mirror.
The translator positions the mirror in the optic path to
direct laser energy from the laser transceiver UUT to the CID video camera. The
translator removes the mirror from the path to permit the optic port to be used for
the laser spot tracker and optical device UUT testing. The mirror is in for laser
transceiver unit UUT tests and out for all other devices.
Two optical switches
sense the mirror in and mirror out positions.
(k) The computer controlled filter wheel/motor assembly is located in the
optic path between the beam sampler and the laser fold mirror assembly. The filter
wheel/motor assembly consists of two flat filter disks, mounted approximately 1/2-inch
apart on a hub assembly.
The disk filters are continuously variable, neutral density
filters with maximum density in the optic path when in the home position. This is
the most counterclockwise position usable on the wheel. There is a clear 40-degree
section of the wheel that is not used.
The filter attenuates the laser energy being
directed to the CID video camera to prevent clipping of the beam signal. The level of
filtering is reduced as testing progresses to permit proper evaluation of the signal.