text: what is a wavefront in simple form, and what about wavefront sensing? i would like a meaning of wavfront in simple form, and also what wavefront sensing is and its relation to shack hartmann. i have seen few websites but most of them are too complex for me to understand. the wavefront of a wave is an imaginary line joinging all the points which are at the same state of vibration together.  this line usually joins the top of wave crests together.  as for wavefront sensing - im not sure