Patent ID: 6211947
Filing Date: 2001-04-03
Classification: G03B,G03F

Abstract:
A method of measuring an illuminance distribution on a surface of a substrate to be exposed while being mounted on a substrate stage;which is characterized in that said method comprises a step of reciprocatively moving said substrate stage in such a manner that a detecting sensor positioned on said substrate stage is moved forward along a route during which said detecting sensor is intermittently stopped at a plurality of locations within an exposure region of the surface of said substrate, and, after reaching a turning location among said plurality of locations, moved to return along said route during which said detecting sensor is intermittently stopped again at said plurality of locations within said exposure region;in that measurement of illuminance is performed an even number of times at each of said plurality of locations except said turning location; andin that said illuminance distribution in said exposure region of the surface of said substrate is determined based not only on a measured value of illuminance obtained at each of said plurality of locations during the forward movement of said detecting sensor but also on a measured value of illuminance obtained at each of said plurality of locations during the returning movement of said detecting sensor.