A method and system are presented for use in controlling the quality of a
reticle. The method includes processing and analyzing reference data and
test data, and generating output data indicative of the current condition
of the reticle. The reference data is indicative of at least a portion of
a reference pattern, which is produced on a reference article by using
said reticle, when in a satisfied condition. The test data is indicative
of a test pattern produced on an identical article using said reticle
when in the current condition, a certain time period after said reticle
has been in use or stored.