Patent ID: 7072503

Claim:
A method of inspecting a stencil having apertures through which a substance is deposited onto an electronic substrate comprising: depositing the substance through the stencil and onto the substrate; capturing a first image of the stencil after the deposit of the substance and detecting variations in texture of the substance in the first image; capturing a second image of the electronic substrate having the substance on its surface and detecting variations in texture of the substance in the second image; defining a region of interest in the first image and in the second image to determine whether at least one feature exists in the region of interest; measuring a first span of the at least one feature in the region of interest in the first image and a second span of the at least one feature in the region of interest in the second image; and correlating the first span of the at least one feature and the second span of the at least one feature to determine whether a threshold span of the at least one feature has been reached.