The TP3-WFS: a new guy in town

The TP3-WFS (Two Pupil Plane Positions Wavefront Sensor) is, to the best of the authors' knowledge, the first physical implementation of the geometrical wavefront reconstruction algorithm that has been tested in a telescope as part of an actual AO-enabled instrument. The main advantage of this algorithm is that it theoretically provides a fairly good reconstruction accuracy even under very low levels of light, in the order of a few hundreds of photons. This paper presents the first control-related results obtained at the William Herschel Telescope (WHT). Such results demonstrate the feasibility of this novel WFS as part of a real-time AO control loop.