Patent ID: 6128127
Filing Date: 2000-10-03
Classification: G01B,G02B

Abstract:
A differential interference contrast microscope of transmission type comprising:an illumination light source means for emitting an illumination light ray;a first polarizing means for converting the illumination light ray emitted from the illumination light source means into a linearly polarized light ray;a polarized light separating means for separating the linearly polarized light ray emanating from the first polarizing means into two linearly polarized light rays propagating in parallel with each other and having mutually orthogonal vibrating directions;an illuminating optical system including a condenser lens for introducing said two linearly polarized light rays having mutually orthogonal vibrating directions onto an object under inspection;an inspecting optical system including an objective lens for inspecting the object under inspection;a polarized light combining means for combining on a sane optical axis said two linearly polarized light rays which were separated to propagate in parallel with each other by said polarized light separating means and transmitted in parallel with each other through the object under inspection; anda second polarizing means for interfering said two linearly polarized light rays combined on the same optical axis with each other to form an interference image;wherein said polarized light separating means is constructed to change an amount of waveftont shear of the two linearly polarized light rays which have mutually orthogonal vibrating directions and which propagate in parallel with each other inspection, and said polarized light combining means is positioned between said object under inspection and said second polarizing means so that said polarized light combining means combines on the same optical axis said two linearly polarized light rays which propagate in parallel with each other in accordance with a variable amount of waveftont shear introduced by said polarized light separating means.