WIYN Observatory

WIYN TECHNICAL SPECIFICATIONS

Optics, General

Primary Diameter 3498.85mm (137.75")
Primary Focal Ratio 1.7505
Tertiary Location Above Primary 475.4mm (18.73")
Baffle Diameter 1446.2mm (56.94") 17.1%

Official Zemax Model

Primary Mirror

Blank Diameter 3511.55mm (138.25")
Diameter (to bevels) 3498.85 (137.75")
Edge Thickness 463.9mm (18.264")
Center Hole Diameter 965.2mm (38")
Sagitta 124.92mm (4.918")
Cass Hole Sagitta 9.4mm (0.370")
Glass Borosilicate
Mirror Weight 196Kg (4320lbs)
Cell Weight 5854Kg (12,280lbs)
CG Location 468mm (18.43") from vertex
Surface Quality 0.025 waves rms
  0.34 waves P-V
  0.09 arcsec FWHM @ 500nm
Surface Roughness 8 Angstrom (average)

Secondary Mirror

Diameter 1200mm (47.25")
Center Thickness 156mm (6.142")
Glass Zerodur
Weight 119.5Kg (263lbs)
Cell Weight 110Kg
Surface Quality 0.024 waves rms
  0.26 waves P-V
Seconday Roughness 11.6 Angstroms average
   
Secondary Articulation  
Focus Travel 1.5cm
Linear Resolution 0.125 micron steps
Pivot Point Location 310mm (12.23") above secondary
Tilt Resolution 0.014 arcsec angular image displacement
Speed 1600 steps per second
  0.09 arcsec FWHM @ 500nm
Surface Roughness 8 Angstrom (average)

Tertiary Mirror

Ellipse Dimensions 1101mm x 776mm (43.35" x 30.55")
Thickness 101.6mm (4.00")
Weight 60Kg (132 lbs)
Cell Weight 76Kg (173 lbs)
Surface Quality 0.026 waves rms
  0.428 waves P-V
  0.022 arcseconds FWHM
Surface Roughness Better than 20 Angstroms

As Built Optical Prescriptions

Effective Focal Length 22004.5
Total Track 4202.87
Image Space F/# 6.28906
Exit Pupil Diameter 1361.08
Exit Pupil Position -8559.89
Back Focal Distance 2706.81
Plate Scale (On Axis) 9.372 arcsec/mm
Distortion 0.002%
  0.2 degree of axis
Magnification 3.5915
Field of View 12 arcmin (aproximate)
Wavelength Coverage Panchromatic
Lens Units Millimeters
   
Surface Radius Thickness Glass Diameter Conic
STO -12253.5 -4202.869 MIRROR 3500 -1.0708
(2) -5332 4202.869 MIRROR 1136.592 -3.74
(3) Infinity -475.4   536.8658 0
(4) Inifinity 0   797.9691 0
(5) Infinity -3182.21 MIRROR 604.2212 0
IMA 0   15.653 0

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Last modified: 03-Apr-2020 10:23:38 MST