Optical phase front measurement unit

A phase front measuring system comprising:

• one or more lenses defining an optical axis;
• a spatial light modulator disposed at the focal plane of said one or more lenses;
• and
• a camera system for taking one more more snapshots and generating quadrature signals;
• and a determining system responsive to said quadrature signals for determining the phase front of a light beam.

A method for determining the phase front of a light beam comprising the steps of:

• (a) providing a pair of spaced apart lenses defining an optical axis;
• (b) providing a spatial light modulator (SLM) at the focal plane of said pair of spaced apart lenses along said optical axis;
• (c) providing a beam splitter along said optical path;
• (d) providing a camera system including a first camera along said optical axis disposed adjacent one end of one lens opposite said SLM and a second camera, said beam splitter and said second camera configured to sample the light beam at said focal plane, said first and second cameras adapted to provide snapshots of said peak intensity and locations of said light beam;
• (e) determining the phase front based on a snapshot from each camera.

A method for determining the phase front of a light beam comprising the steps of:

• (a) providing a lens defining first optical axis;
• (b) providing a reflective spatial light modulator (SLM) along said optical path;
• (c) providing a quarter wave plate and a polarizing beam splitter along said first optical axis, said polarizing beam splitter reflecting a portion of said light beam along a second optical axis;
• (d) providing a camera system away from said optical axis configured to said camera providing quadrature signals of said light beam;
• (e) determining the phase front based on said quadrature signals from said camera system.