Patent ID: 6509964
Filing Date: 2003-01-21
Classification: G01N

Abstract:
An apparatus for measuring the visual characteristics of a surface of a workpiece, said apparatus comprising:a first light source operative to direct at least one focused beam of light onto a surface of a workpiece for reflection therefrom so as to produce a first set of reflected beams, each beam of said first set corresponding to one of said at least one focused beams; a second light source operative to direct at least one unfocused beam of light onto said surface of said workpiece for reflection therefrom, at a location separate from a location at which each of said at least one focused beams are directed onto said workpiece, so as to produce a second set of reflected beams, each beam of said second set corresponding to one of said at least one unfocused beams; a photo detector operative to produce a signal in response to illumination thereof; means for directing said first and second sets of reflected beams of light onto said photo detector; and multiplexing means for causing said photo detector to sequentially detect each member of said first and second sets of reflected beams, whereby said photo detector produces a separate signal in response to each of said reflected beams.