Apparatus and methods for contour measurement using movable sources

An apparatus for determining, on an object having a surface, position information of a point on said surface of said object, said apparatus comprising:

• two sources of radiation separated by a distance, said sources being coherent with respect to one another;
• a control system moving each of said sources relative to each other;
• a detector positioned to receive radiation scattered from said point on said surface of said object;
• and
• a processor receiving signals from said detector, said processor calculating position information in response to said movement of said sources and said received radiation scattered from said point on said surface of said object.

A method for determining, on an object having a surface, position information of a point on said surface of said object, said method comprising the steps of:

• providing two sources of radiation separated by a distance, said sources being coherent with respect to one another;
• providing a detector at said point on said surface;
• illuminating said point on said surface of said object with said radiation from each of said sources;
• moving each of said sources relative to each other;
• detecting said radiation at said point on said surface of said object;
• and
• calculating position information in response to said movement of said sources and said radiation detected at said point on said surface of said object.

An apparatus for determining, on an object having a surface, a depth coordinate of a point on said surface of said object, said apparatus comprising:

• two sources of radiation separated by a distance, said sources being coherent with respect to one another;
• a control system moving each of said sources relative to each other;
• a detector positioned at said point on said surface of said object to receive radiation illuminating said point on said surface of said object;
• and
• a processor receiving signals from said detector, said processor calculating position information of said point on said surface of said object in response to said movement of said sources and said radiation received at said point on said surface of said object.