|
WISH Filter Wheel
1段4ポジション×2段の場合（フィルタは6枚） |
JWST/NIRCam Filter Wheel |
JWST/NIRSpec Filter Wheel |
| Number of Positions |
8 (4 positions x 2 wheels ?) |
24 (12 positions x 2 wheels)
Pupil Wheel(PW): wave-front-sensing elements,filters,weak lenses
Wilter Wheel(FW):4° tilteted
8 broad-band
12 intermediate
9 Narrow-band
NIRcam Filters Sensitivities
|
8
3 longpass filters
3 broad-band filters
1 CaF2 Plate as clear aperture
1 Shutter/Diffuser component
|
| Filter Material |
Si ? |
|
CaF2, BK7 |
| Filter Diameter, Thickness |
Φ140 mm |
Φ 48 mm, t=5mm(FW),10mm(PW) |
|
| Wheel Diameter |
Φ440 mm |
Φ290 mm |
Φ307 mm |
| Total Mass |
350gx6=2100g(Si Filters)+
6300 g (Filter Wheel Structure) +
|
|
6500 g (Mechanism Support) +
2250 g (Filter Wheel Structure) +
350 g (Other)=
9100 g |
| Static Qualification Load |
|
|
30 G |
| Material |
|
|
MS: Ti-6Al-4V
FWS: Al5456 |
| Motor |
|
Custom rotor, d=3.6" 3-phase,
brushless DC motor
130mA(high torque const.) |
|
| Bearing |
|
duplex bearing
35mmOD and 17mmID
dry-film lubricated cage |
|
| Operating Temperature |
|
32-37 K
(Survival Temp.=20-330K) |
|
| Position Sensing |
|
inductive sensors |
|
| Test |
|
Thermal cycles,
Operation 2400 revolutions at 20K |
|
| Optical Requirement |
|
Surface Figure <λ/10 P-V*0.022&;lambdarms)@λ=633nm
Scratch/Dig=40/20
Surface Roughness <20Årms
Dimensional Tolerance=±0.05mm
Edge and chamfers=Polished or acid-etched |
|
| Memo |
|
較正用光源も一緒にマウントされている |
|
