Zone analysis system and method for optimizing the performance of an inspection system for determining disparity between two surfaces

A zone analysis method for optimizing speed and minimizing adverse effects resulting from noise in an inspection system for measuring disparity between first and second surfaces, said first surface surrounding said second surface, the method comprising the following steps that are performed automatically with said inspection system:

• (a) capturing an image of said surfaces with an interferometric fringe superimposed over said image and over said surfaces;
• (b) isolating zones in said image for analysis, while discarding regions characterized by noise, by:
• (1) defining first and fourth zones in said image over said first surface and said fringe on opposing sides of said second surface;
• and
• (2) defining second and third zones over said second surface and said fringe on opposing sides of a center of said second surface;
• (c) arithmetically fitting a first equation to said fringe in said first and fourth zones;
• (d) arithmetically fitting a second equation to said fringe in said second and third zones;
• and
• (e) determining said disparity between said first and second surfaces based upon said first and second equations.

A zone analysis system for optimizing speed and minimizing adverse effects from noise in an inspection system for measuring disparity between first and second surfaces, said first surface surrounding said second surface, the system comprising:

• (a) means for capturing with said inspection system an image of said surfaces with an interferometric fringe superimposed over said image and over said surfaces, said interferometric fringe being a highest gradient fringe of an interferometric pattern produced with white light;
• and
• (b) means for performing automatically with said inspection system the following:
• (1) defining first and second zones in said image over said first and second surfaces respectively as well as said fringe;
• (2) arithmetically fitting first and second equations to said fringe in said first and second zones respectively;
• and
• (3) determining said disparity between said first and second surfaces based upon said first and second equations.

A zone analysis system for optimizing speed and minimizing adverse effects resulting from noise in an inspection system for measuring disparity between first and second surfaces, said first surface surrounding said second surface, the system comprising:

• (a) means for capturing an image of said surfaces with an interferometric fringe superimposed over said image and over said surfaces;
• (b) means for isolating in said image for analysis, while discarding regions characterized by noise, by:
• (1) defining first and fourth zones in said image over said first surface and said fringe on opposing sides of said second surface;
• and
• (2) defining second and third zones over said second surface and said fringe on opposing sides of a center of said second surface;
• (c) means for arithmetically fitting a first equation to said fringe in said first and fourth zones;
• (d) means for arithmetically fitting a second equation to said hinge in said second and third zones;
• and
• (e) means for determining said disparity between said first and second surfaces based upon said first and second equations.