  The Santa Cruz Extreme AO Lab (SEAL) is a new visible-wavelength testbed
designed to advance the state of the art in wavefront control for high contrast
imaging on large, segmented, ground-based telescopes. SEAL provides multiple
options for simulating atmospheric turbulence, including rotating phase plates
and a custom Meadowlark spatial light modulator that delivers phase offsets of
up to 6pi at 635nm. A 37-segment IrisAO deformable mirror (DM) simulates the W.
M. Keck Observatory segmented primary mirror. The adaptive optics system
consists of a woofer/tweeter deformable mirror system (a 97-actuator ALPAO DM
and 1024-actuator Boston Micromachines MEMs DM, respectively), and four
wavefront sensor arms: 1) a high-speed Shack-Hartmann WFS, 2) a reflective
pyramid WFS, designed as a prototype for the ShaneAO system at Lick
Observatory, 3) a vector-Zernike WFS, and 4) a Fast Atmospheric Self Coherent
Camera Technique (FAST) demonstration arm, consisting of a custom focal plane
mask and high-speed sCMOS detector. Finally, science arms preliminarily include
a classical Lyot-style coronagraph as well as FAST (which doubles as a WFS and
science camera). SEAL's real time control system is based on the Compute and
Control for Adaptive optics (CACAO) package, and is designed to support the
efficient transfer of software between SEAL and the Keck II AO system. In this
paper, we present an overview of the design and first light performance of
SEAL.
