Method of and apparatus for inspection of coatings on surfaces

Claim 3

The method as set forth in claim 1 wherein said directing step includes directing said beams at an angle of incidence of between 20° an 80°.

Claim 4

The method as set forth in claim 2, wherein said angle of incidence is close to 75 degrees.

Claim 5

The method as set forth in claim 1, wherein said responding step includes visually comparing said polarized sample reflected beams and said polarized reference reflected beams through said analyzer.

Claim 6

The method as set forth in claim 4, wherein said at least one reference coated substrate is selected to represent a coating or predetermined minimum acceptable quality regard to minimum coating thickness and maximum variations in thickness.

Claim 7

The method as set forth in claim 5, wherein said at least one reference coated substrate is selected by analyzing coated glass substrates using spectroscopic means to select a sample representng a coating of predetermined minimum acceptable quality with regard to minimum coating thickness and maximum variations of thickness, and wherein further, if the substrate under inspection appears darker overall, through said analyzer, than said reference coated substrate, then the substrate coating is too thin, and if the shading across the substrate varies more than on said reference coated substrate, it is of unacceptable quality with respect to coating uniformity.

Claim 10

The method as set forth in claim 7, wherein said analyzer positioning step includes positioning said analyzer in the path of the reflected beams to vertically polarize said reflected beams.

Claim 11

Apparatus for inspecting coatings on a substrate, comprising: a light source for generating light beams; means for directing said beams toward the coating to be inspected to provide reflected energy beams including at least a portion reflected from the upper surface of the coating; means for vertically polarizing said reflected light beams to provide polarized reflected beams; and means for recording image or shading pattern produced on said polarizing means by said reflected light beams passing therethrough.

Claim 12

Apparatus for inspecting coatings on a substrate, comprising: a light source for generating light beams; means for directing said beams toward the coating to be inspected to provide reflected energy beams including at least a portion reflected from the upper surface of the coating; means for vertically polarizing said reflected light beams to provide polarized reflected beams; and means for recording image or shading pattern produced on said polarizing means by said reflected light beams passing therethrough.