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Questions about the BatchPCB service

Moderator: robacarp

By dhouston
#4268
Dictionary.com defines annulus as...

"Mathematics: The figure bounded by and containing the area between two concentric circles."

IOW its thickness is the difference between the radii of the two concentric circles. My board layout software (and most board layout software) uses the mathematical definition in design rule checks.

Sparky's drawing eliminates any confusion.