Abstract: Methods for characterizing the surface shapes of optical elements include the following steps: carrying out, in an interferometric test arrangement, at least a first interferogram measurement on the optical element by superimposing a test wave, which has been generated by diffraction of electromagnetic radiation on a diffractive element and has been reflected at the optical element, carrying out at least one additional interferogram measurement on in each case one calibrating mirror for determining calibration corrections, and determining the deviation from the target shape of the optical element based on the first interferogram measurement carried out on the optical element and the determined calibration corrections. At least two interferogram measurements are carried out for the at least one calibrating mirror, which differ from one another with regard to the polarization state of the electromagnetic radiation.

Abstract: Methods for characterizing the surface shapes of optical elements include the following steps: carrying out, in an interferometric test arrangement, at least a first interferogram measurement on the optical element by superimposing a test wave, which has been generated by diffraction of electromagnetic radiation on a diffractive element and has been reflected at the optical element, carrying out at least one additional interferogram measurement on in each case one calibrating mirror for determining calibration corrections, and determining the deviation from the target shape of the optical element based on the first interferogram measurement carried out on the optical element and the determined calibration corrections. At least two interferogram measurements are carried out for the at least one calibrating mirror, which differ from one another with regard to the polarization state of the electromagnetic radiation.

Abstract: A method and a device for characterizing the surface shape of an optical element. In the method, in at least one interferogram measurement carried out by an interferometric test arrangement, a test wave reflected at the optical element is caused to be superimposed with a reference wave not reflected at the optical element. In this case, the figure of the optical element is determined on the basis of at least two interferogram measurements using electromagnetic radiation having in each case linear input polarization or in each case circular input polarization, wherein the input polarizations for the two interferogram measurements differ from one another.

Abstract: A method and a device for characterizing the surface shape of an optical element. In the method, in at least one interferogram measurement carried out by an interferometric test arrangement, a test wave reflected at the optical element is caused to be superimposed with a reference wave not reflected at the optical element. In this case, the figure of the optical element is determined on the basis of at least two interferogram measurements using electromagnetic radiation having in each case linear input polarization or in each case circular input polarization, wherein the input polarizations for the two interferogram measurements differ from one another.

Abstract: A visualization apparatus for a surgical site includes a recording unit for recording an image of an object arranged in a focal plane of the recording unit. The recording unit has a lens having an optical axis that intersects the focal plane at a point P. An electronic image representation unit has an image surface for reproducing the recorded image and point P is reproduced at image point P?. A mirror unit has a mirror surface, which has a center point S and is arranged relative to the image surface such that the reproduced image is reflected by the mirror surface. The focal plane, image surface and mirror surface are arranged relative to one another such that an observation point B results for which the following applies: ?2 D<?1??2<+2 D; wherein: ?1=?1/d1 ?2=?1/d2 d1=distance PB d2=distance P?S+distance SB.

Abstract: A visualization apparatus for a surgical site includes a recording unit for recording an image of an object arranged in a focal plane of the recording unit. The recording unit has a lens having an optical axis that intersects the focal plane at a point P. An electronic image representation unit has an image surface for reproducing the recorded image and point P is reproduced at image point P?. A mirror unit has a mirror surface, which has a center point S and is arranged relative to the image surface such that the reproduced image is reflected by the mirror surface. The focal plane, image surface and mirror surface are arranged relative to one another such that an observation point B results for which the following applies: ?2 D<?1??2<+2 D; wherein: ?1=?1/d1 ?2=?1/d2 d1=distance PB d2=distance P?S+distance SB.