WM Keck Observatory's Next Generation Adaptive Optics Facility

W. M. Keck Observatory (WMKO) is Currently engaged in the design of a powerful new Adaptive Optics (AO) science capability providing precision correction in the near-IR, good correction in the visible, and faint object multiplexed integral field spectroscopy. Improved sensitivity will result from significantly higher Strehl ratios over narrow fields (< 30" diameter) and from lower backgrounds. Quantitative astronomy will benefit from improved PSF stability and knowledge. Strehl ratios of 15 to 25% are expected at wavelengths as short as 750 nm. A multi-object AO approach will be taken for the correction of multiple science targets over modest fields of regard (< 2' diameter) and to achieve high sky coverage using AO compensated near-IR tip/tilt sensing. In this paper we present the conceptual design for this system including discussion of the requirements, system architecture, key design features, performance predictions and implementation plans.