stack on bench. Note geared HWP cell in place
||Test slit belt.
Steel belt of thickness 0.003" with laser cut holes on one edge
to engage the cog drive.
resting atop back of filter box. The detector mount consists of the
central polished aluminum block containing the detector socket and
fanout board - this unit was manufactured by MKIR in Hawaii. Surrounding
it is the detector mount "cage" or bracket. The detector
block is cooled to 34K through the copper post seen at left. The cage
is bolted to the back of the filter box and so is at 70K. The block
and cage are connected via four G10 "V-tabs" that provide
good thermal insulation and precise location of the detector relative
to the optical beam. The block and the inner part of the cage are
highly polished to reduce radiative thermal coupling between them.
||Side view of
detector cage and block showing one of the four G10 V-tabs that connect
between them. Also seen on the back of the detector mount block are
one of the two VME connectors carrying the detector signals and the
8x1 IDC pin connector to the temperature sensor and resistive heaters
used to create closed loop temperature control of the detector.
of detector block, cage, and G10 V-tab. Note the short "snout"
on the front of the detector block. This piece was fabricated in the
BU SIF and contains find rulings inside the snout to act as a corregated
light baffle. The snout protrudes into the filter box camera bay,
and stops only some 0.020-0.032" from the camera block.
showing the cold strap copper post. This is the thermal connection
that goes to the second stage of the CTI refrigerator to cool the
detector block to the 34 K needed for optimal operation.
||Back view of
detector block and cage, on the back of the filter box. The cage is
located precisely by three shoulder bearing collars on pins in the
back of the filter box. One shoulder bearing is at center right, a
second is at center left.
detector block and cage is the cover, consisting of the four-sided
collar shown here and the flat cover that seals the top opening. This
box is light-tight, but passes the cold strap to the detector (copper
feed through just up and left of center) as well as the detector signals
(through epoxied IDC connectors -- not yet installed in this picture).
on detector unit box, mounted on back of filter box.
On the bottom
of the filter box, there are the openings and tapped holes that
will accept the hardened steel insert pieces that form half of the
kinematic mounts for the filter box and collimator.
||Side view of
detector box on back of filter box.