Patent ID: 7961334

Claim:
A coordinate measuring machine ( 1 ) for measuring structures ( 3 ) on a substrate ( 2 ) comprising a measurement table ( 20 ) movable in the X-coordinate direction and in the Y-coordinate direction, a measurement objective ( 9 ), at least one laser interferometer ( 24 ) for determining a position of the measurement table ( 20 ) or the measurement objective ( 9 ) or both, and having an illumination condenser ( 8 ) for transmitted light illumination of the substrate ( 2 ), wherein the measurement table ( 20 ), the measurement objective ( 9 ), the at least one laser interferometer ( 24 ) and the illumination condenser ( 8 ) are partially arranged in a vacuum chamber ( 50 ) provided with at least one window ( 52 ), wherein the at least one window ( 52 ) is transparent for enabling illumination and a measurement wavelength from the measurement objective ( 9 ) and the laser interferometer ( 24 ) and the illumination condenser ( 8 ) into the vacuum chamber ( 50 ).