Patent ID: 7456947
Filing Date: 2008-11-25
Classification: G01N

Abstract:
1. An inspecting apparatus for inspecting a substrate by magnifying a surface of the substrate, comprising: an objective lens attaching part equipped with plural objective lenses, each having a different working distance, and which positions one of the objective lenses in an inspecting light path; an objective lens exchanging device which actuates the objective lens attaching part to exchange the objective lens which is disposed in an inspecting light path; a loading stage which is opposed to the objective lens disposed in the inspecting light path, and on which the substrate is loaded so that the surface of the substrate crosses an optical axis of the inspecting light path substantially rectangularly; an objective lens detecting device which determines the working distance of the objective lens disposed in the inspecting light path; a displacing device which relatively displaces the objective lens disposed in the inspecting light path and the loading stage in a direction of the optical axis of the inspecting light path and in a direction rectangular to the optical axis; and a displacement controlling device to control the relative displacement of the objective lens and the loading stage in the direction rectangular to the optical axis by the displacing device when the lens detecting device detects that the working distance of the objective lens disposed in the inspecting light path is shorter than a predetermined working distance, in order to prevent the objective lens from interfering with the substrate.