Abstract: An interferometer includes a light source, adapted to generate a coherent light beam, a detector adapted to analyze the phase difference of optical light beams, a location unit for locating an object to be measured, a first optical path from the light source to the object and a second optical path from the object to the detector. The first and the second optical path have a common section adjacent to the object. An optical polarization modulator has been arranged in the first path.

Abstract: An optical system includes an optical unit with an optical axis extending through a light transmissive sample embedded in a transparent substrate, to focus on the sample embedded in the substrate and to scan the sample according to the main plane of the transparent substrate. The optical axis extends under an angle unequal to zero relative to the normal of the main plane of the transparent substrate, in order to perform a volumetric observation of a sample by obtaining information items focused in all thickness directions within the sample, at a high speed, without requiring any movement along the thickness direction of the sample.

Abstract: The invention relates to an interferometer, comprising a light source, adapted to generate a coherent light beam, a detector adapted to analyze the phase difference of optical light beams, location means for locating an object to be measured, a first optical path from the light source to the object and a second optical path from the object to the detector, wherein the first and the second optical path have a common section adjacent to the object, wherein an optical polarization modulator has been arranged in the first path. This avoids the costs and other disadvantages of so called quarter wave plates belonging to prior art interferometers of this kind.

Abstract: An optical system is provided to include an optical unit with an optical axis extending through a light transmissive sample embedded in a transparent substrate, to focus on the sample embedded in the substrate and to scan the sample according to the main plane of the transparent substrate. The optical axis extends under an angle unequal to zero relative to the normal of the main plane of the transparent substrate, in order to perform a volumetric observation of a sample by obtaining information items focused in all thickness directions within the sample, at a high speed, without requiring any movement along the thickness direction of the sample.