Adaptive Optics and Astronomy

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Adaptive Optics and Astronomy

• Cabrillo College
• Sandra M. Faber
• 7 March 2001

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What is the CfAO?

• The CfAO is an NSF Science and Technology Center
• We started November 1999
• We have a 5-year lifetime, extendable to 10 years
• The CfAO is a multi-institutional center
• Headquarters at UC Santa Cruz
• UC Berkeley, UC San Diego, UCLA
• Caltech, Chicago, Rochester, Houston, Indiana,
  Lawrence Livermore Lab
• Industrial partners Lucent, Bausch Lomb,
  Rockwell, and others
• The CfAO contains about 200 faculty, postdocs,
  graduate students, and industrial researchers
• We have a major outreach program aimed at
  attracting minority students into math and
  science

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Basic idea of AO
Wavefront corrector
Aberrated wavefront
Corrected wavefront
Wavefront sensor
Wavefront control computer
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The Deformable Mirror
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PSF Changes with Pupil Size
1 mm
2 mm
3 mm
4 mm
pupil images followed by psfs for changing
pupil size
5 mm
6 mm
7 mm
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Why Correct the Eyes Optics?
Perfect Eye
Aberrated Eye
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The Rochester Adaptive Optics Ophthalmoscope
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No Adaptive Optics
With Adaptive Optics
JW right eye 1 deg eccentricity image wavelength
550 nm April 21, 1997
10 arc min (48.6 µm)
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Retinal Imaging Basic Science
Scale bar 5 µm
First images of the trichromatic photoreceptor
mosaic in the human eye (Roorda and Williams,
Nature, 1999)
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Adaptive optics provides a clear improvement in
retinal image quality
Wave Aberration
Point Spread Function
Retinal Image at 550nm
Retinal Image in White Light
Before adaptive optics
1 deg
After adaptive optics
YY
6.8 mm pupil
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Schematic of Astronomical AO System
Telescope

Deformable mirror
Tip-tilt mirror
Beam splitter
Wavefront sensor
Tip-tilt sensor
Beam splitter
Imaging camera
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Neptune at 1.65 microns
Without adaptive optics
With adaptive optics
2.3 arc sec
May 24, 1999
June 28, 1999
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View of Lunar Eclipse