Transcript Presentation (.pptx)

Mechanical Changes Required Due
to Proposed IRMS Rx
V2
R. Weber
September 27, 2011
Windows & CSU
• No changes required for
window mounts
• Because of the flip in
curvature of the focal
surface, the CSU supports
will need to be shortened
by ~4 mm so that the focus
is at the incoming edge of
the central masking bar,
rather than the exiting
edge. Or, the instrument
could be positioned ~4 mm
further from NFIRAOS.
Masking bar thickness
Keck focus
(ends of ray pencils)
9/8/2011
TMT focus
(blue arc)
2
Field Lens
• Girdle thickness
increased from
11.5 to 12.9
mm- better for
bonding
• Center of girdle
shifted 2.694
mm towards
CSU- lens
mount flexure
pockets
machined
deeper in cell
9/8/2011
IRMS (transparent)
MOSFIRE (solid)
3
Collimator Barrel
IRMS lenses
•
•
•
(transparent)
MOSFIRE lenses
(solid)
Girdle center shifts: Col
#2= -0.5 mm, Col #3= 2.7
mm, Col #4= 1.6 mm, Col
#5= 0.03 mm, Col #6= 0.05 mm.
These relatively small
shifts in the lens girdle
centers should be
achievable through a
combination of cell spacer
shim alterations and/or
altering mount flexure
pocket depths.
Girdle widths are all
comparable or slightly
larger than MOSFIRE
design- no bonding issues.
9/8/2011
4
Camera Barrel: (Cells #1-#4)
•
•
•
•
Cell #1: girdle center shifts -2.0
mm and girdle thickness
increases by 0.8 mm to 12.0
mm; minor cell spacer shim
modifications required.
Cell #2: girdle center shifts -1.6
mm and girdle thickness
remains the same; minor cell
spacer shim modifications
required.
Cell #3: girdle center shifts -1.9
mm and girdle thickness
decreases by 0.7 mm to 52.7
mm; minor cell spacer shim
modifications required.
Cell #4: girdle center shifts -1.9
mm and girdle thickness
increases by 0.6 mm to 11.1
mm; minor cell spacer shim
modifications required.
9/8/2011
IRMS lenses
(transparent)
MOSFIRE lenses
(solid)
5
Camera Barrel: (Cells #5, #6, & Field
Flattener/Detector)
MOSFIRE lenses
•
•
•
Cell #5: girdle center shifts 0.8 mm and girdle thickness
increases by 1.8 mm to 9.9
mm; minor cell spacer shim
modifications required.
Cell #6: girdle center shifts 1.4 mm and girdle thickness
decreases by 2.2 mm to 26.3
mm; minor cell spacer shim
modifications required.
Field flattener/detector:
girdle center shifts -1.2 mm
and girdle thickness
increases by 0.6 mm to 9.9
mm; minor cell spacer shim
modifications required.
9/8/2011
IRMS focal surface
IRMS lenses
(transparent)
(solid)
6