Patent ID: 7633675
Filing Date: 2009-12-15
Classification: G02B,G03F

Abstract:
1. An objective employed for use in inspecting a specimen, comprising: a focusing lens group configured to receive light energy and comprising at least one focusing lens; at least one field lens oriented to receive focused light energy from said focusing lens group and provide intermediate light energy; a Mangin mirror arrangement positioned to receive the intermediate light energy from the field lens and form controlled light energy, said Mangin mirror arrangement comprising at least three axially distributed elements comprising at least two elements having reflective surfaces; and an immersion substance located between said Mangin mirror arrangement and said specimen; said Mangin mirror arrangement imparting the controlled light energy to the specimen with a numerical aperture in excess of 0.9 and a field size of greater than or equal to approximately 0.10 mm; wherein all lenses are constructed of a single glass material.