Device for Determining the Position of at Least One Structure on an Object, Use of an Illumination Apparatus with the Device and Use of Protective Gas with the Device

Abstract

A device for determining the position of a structure ( 3 ) on an object ( 2 ) in relation to a coordinate system is disclosed. The object ( 2 ) is placed on a measuring table ( 20 ) which is movable in one plane ( 25 a ), wherein a block ( 25 ) defines the plane ( 25 a ). At least one optical arrangement ( 40, 50 ) is provided for transmitted light illumination and/or reflected light illumination. The optical arrangement ( 40, 50 ) comprises an illumination apparatus ( 41, 51 ) for reflected light illumination and/or transmitted light illumination and at least one first or second optical element ( 9 a, 9 b ), wherein at least part of the at least one optical element ( 9 a, 9 b ) extends into the space ( 110 ) between the block ( 25 ) and an optical system support ( 100 ). The block ( 25 ) and/or the optical system support ( 100 ) separates the illumination apparatus ( 41, 51 ) spatially from the plane ( 25 a ) in which the measuring table ( 20 ) is movable.

1 . The use of protective gas in a device for determining the position of at least one structure on an object, wherein at least one optical component in a path of the light from at least one illumination apparatus to at least one optical element is surrounded by protective gas. 
     
     
         2 . The use according to  claim 1 , wherein all the optical components in the path of the light from the at least one illumination apparatus to the optical elements are surrounded by protective gas, wherein, for this purpose, the optical components are surrounded by an encapsulation and the light from the at least one illumination apparatus runs within the encapsulation. 
     
     
         3 . The use according to  claim 1 , characterized in that the optical components comprise at least one shutter, at least one beam attenuator, at least one apparatus for speckle reduction and/or at least one homogeniser, as well as at least one optical element.