Study of local minima in metric adaptive optics

Metric adaptive optics systems search over a set of wavefront modes or commands to actuators to optimize a system performance metric like Strehl ratio or brightness. These systems have been explored for many decades and have been thought to be unreliable due to local minima in the metric space. It has been shown that some modes match well with no local minima to a given metric, but they rely on the ability of a mirror to create reliable replicas of the search modes. We present here a study of the most common implementation of metric adaptive optics that involves searching over the actuator command space while evaluating an intensity-based metric. We map an error space relating a common metric to actuator commands and statistically analyze the error function to determine the quantity and location of the local minima.