The wavefront sensor (WFS) for the Large Binocular Telescope is based on a pyramid sensor with a maximum sampling
of 30x30 subapertures.
In particular the pyramid used in the WFS is a Double Pyramid (DP). This for two reasons: the first is that so doing it is
possible to have pyramids with a base angle greeter than the angle of a single pyramid so that athe polishing process is
made easier. The second is that it is possible to reduce the chromatic effects that the use of a single pyramid introduces.
This enables to work with a larger wavelenght range.