Laboratory for Adaptive Optics

Laboratory for Adaptive Optics
UCO Lick Observatory
University of California, Santa Cruz

LAO CfAO UC Observatories Lick Observatory UC Santa Cruz

LAO Publications UCO/Lick Observatory Center for Adaptive Optics (CfAO) Internal Documents (local only) Astro 205 presentation Sodium Laser Guidestar Workshops

The Laboratory for Adaptive Optics enables hands-on exploratory research in the development of the technology for future implementations of adaptive optics systems on astronomical telescopes

LAO Yearly Status Reports: 2003 2004 2005 2006 2007 2008 2009

Projects

Extreme Adaptive Optics Planet Imager

Over 400 planets around nearby stars have been discovered through indirect means, however only a few have been detected directly by their own light. For planet characterization in its own light, the instrument must be of extraordinarly high contrast to separate the planet out of the glare of light from its parent star. "Extreme" adaptive optics (ExAO) achieves this high contrast by using a precise and high-speed adaptive optics system. An ExAO instrument looks in only a narrow field around the parent star and uses the star's light as its wavefront reference beacon. High precision wavefront control is achieved with a micro electromechanical system (MEMS) deformable mirror. The ExAO laboratory contains a prototype ExAO system with a high-order MEMS mirror and a coronagraph, combined with a precision phase-shifting diffraction interferometer (PSDI) and science grade CCD for characterization of the wavefront quality and image plane contrast properties. ExAO system development has led to a project to build and commission the Gemini Planet Imager (GPI) instrument for the 8 meter Gemini Telescope. Ongoing laboratory research work will include design and testing of concepts for even higher contrast instruments for a 30 meter class ground-based telescope and space-based telescopes of the future.

Laser Tomography Adaptive Optics (LTAO) testbed

The Laser Tomography Adaptive Optics testbed is used for testing system concepts for future wide-field adaptive optics systems for 8-meter to 30-meter primary mirror diameter class telescopes. We are exploring new technologies that include the use of multiple laser guide stars in a tomographic reconstructor and the use of multiple deformable mirrors to correct the atmosphere either at conjugate layer heights in the atmosphere or at multiple astronomical target points in the field of view.

Adaptive Optics Component Testing

New concepts and materials for wavefront sensing and wavefront correction will be required for the next generation of adaptive optics instruments. We are collaborating with researchers from industry and academia to develop technology in the areas of high speed low noise wavefront sensor detectors, MEMS deformable mirrors, and real-time computers.

The Laboratory for Adaptive Optics is made possible through a generous donation from the Gordon and Betty Moore Foundation.

Just a plan...	Tables, and populating with equipment
Grand Opening	Grad Student working hard

Laboratory Facility	Present situation: ~300 sq ft in the Lick Optical Shops High bay plus ~500 sq ft in Thimann Laboratories Building By early 2005: 1900 sq ft in Thimann Laboratories Building in two separate rooms Lab area clean to class 10,000 standards Class 100 cleanroom area Temperature control Light control
Optical Benchs	18 x 4 ft granite optical table (ExAO testbed) 6 x 6 ft granite optical table (cleanroom/assembly/test area) 2 16 x 4 ft Newport optical tables (MCAO testbed, wavefront sensing and control experiments, interferometers)
Interferometers	Phase-shifting Diffraction Interferometer (PSDI) - ~1 nm rms absolute wavefront accuracy over a 10-20 mm area - ExAO prototype evaluation and calibration Zygo Fizeau Interferometer - 4" aperture with 6 x zoom, 1000x1000 resolution, 4" window and flat with lambda/20 certification - general purpose optical testing Polarization Quadrature Interferometer - high speed (30 Hz) phase determination on 20 mm square aperture - used for testing spatial light modulators
Deformable Mirrors	32 x 32 MEMS device (continuous face sheet) from Boston Micromachines - for the ExAO prototype 4 768 x 768 pixel liquid crystal spatial light modulators from Hamamatsu - surrogate DMs for the MCAO testbed Intellite 36 element membrane DM - for AO demonstration and controls research
Cameras	3 1024 x 1024 Dalsa 1M30 cameras - wavefront sensors for the MCAO testbed (up to 4 guidestars per camera) 2 additional 1024 x 1024 Dalsa 1M30 cameras - wavefront sensing in the ExAO prototype 1K x 1K CCD camera from Princeton Instruments with E2V CCD47-10 science grade chip - for far-field high-contrast measurements on the ExAO testbed
Wavefront Aberration Plates	Etched glass 150 x 150 mm area with Kolmogorov spectrum, 40 micron features (4K x 4K), 8 bit resolution, 25 micron peak optical path difference - for testing ExAO or MCAO systems with simulated atmospheric turbulence - we only have 2 of these now but plan to replicate them at various peak optical path specification for use as simulated atmospheric layers.
Computing	Quad 3.04 Gigahertz CPU with 8 GBy RAM, 4 MBytes cache - for real-time MCAO tomography and wavefront control. This is sufficient for 9 laser guidestars and 4 deformable mirrors with a 5 Hz control loop update rate. CPU idle time can be used for simulation runs.

Projects

Documents Archive

Project Posters

Laboratory Photos

Description of Facilities