Abstract: The invention is directed to a method of differential interference contrast in which the object is illuminated by natural light and the light coming from the object is first polarized after passing through the objective. The observation is carried out with a shearing interferometer which is known per se.

Abstract: The invention is directed to a method of differential interference contrast in which the object is illuminated by natural light and the light coming from the object is first polarized after passing through the objective. The observation is carried out with a shearing interferometer which is known per se.

Abstract: The invention describes the use of multiphoton laser scanning microscopy in material analysis, especially in the analysis of structured silicon wafers by using non-optical detection techniques such as, e.g., OBIC (optical beam induced current) or LIVA (light induced voltage alteration). OBIC and LIVA make use of the generation of an electron-hole charge carrier current or a change in potential due to the scanning laser beam to localize lattice defects in crystalline materials, especially p-n junctions. By using the high localization of the multiphoton excitation in all three spatial coordinates using high-aperture microscope objectives in laser scanning microscopy, this technique enables nondestructive three-dimensional localization of crystal defects.

Abstract: An achromatic phase retarder comprises at least one prismatic body with two total reflection surfaces. The light entry surface forms an angle of incidence .alpha., which is different from 90.degree., with the direction of incidence of a light beam, and a first total reflection surface forms a defined angle .phi. with the light entry surface.