Abstract: A method for determining optical properties of a sample material includes: determining a first intensity of light in a first polarization state that was reflected by the sample material; determining a second intensity of the light in a second polarization state that was reflected by the sample material; forming the ratio between the first intensity and the second intensity, or vice versa. Further, an apparatus for determining optical properties of a sample material, comprising at least one detector device for determining a first intensity of light in a first polarization state that was reflected by the sample material and for determining a second intensity of the light in a second polarization state that was reflected by the sample material and at least one computing unit for forming the ratio of the first intensity and the second intensity, or vice versa.

Abstract: The invention relates to a device and a method for checking human vision, comprising an image-generating module for generating any test images, an imaging module, used to image the test image provided by the image-generating module on the retina of the eye as a stimulus, the imaging module containing at least one optical component having variable focal length, such that the test image of the image-generating module is perceptible to the eye from virtually simulated and variable distances, an accommodation measuring apparatus, a viewing direction measuring apparatus, and a control and evaluation module, which records and/or further processes the information. The accommodation of the eye can be stimulated by means of the particular test image, and the viewing direction of the eye can be measured simultaneously or in alternation, and fed to a control and evaluation module. Both eyes can be checked simultaneously by generating virtual binocular images.

Abstract: The invention relates to a method for photographically observing and/or documenting the fundus of an eye, comprising: producing a lighting beam path by means of a lighting module for lighting at least one partial area of the fundus by using an at least approximately punctiform or at least areally limited lighting source, producing an image plane in the lighting beam path for the creation of photographic recordings, separating the pupil cross-sectional area into a detectable observation region and an undetectable lighting region, producing an image area that contains the image of the fundus on the image plane, dividing the image area in strips in the lighting beam path into a lighted region and unlighted regions, and imaging the third and fourth Purkinje reflection on the image area, wherein at least one Purkinje reflection, the third and/or fourth Purkinje reflection, is located in the unlighted regions of the image area.

Abstract: The invention relates to a device and a method for checking human vision, comprising an image-generating module for generating any test images, an imaging module, used to image the test image provided by the image-generating module on the retina of the eye as a stimulus, the imaging module containing at least one optical component having variable focal length, such that the test image of the image-generating module is perceptible to the eye from virtually simulated and variable distances, an accommodation measuring apparatus, a viewing direction measuring apparatus, and a control and evaluation module, which records and/or further processes the information. The accommodation of the eye can be stimulated by means of the particular test image, and the viewing direction of the eye can be measured simultaneously or in alternation, and fed to a control and evaluation module. Both eyes can be checked simultaneously by generating virtual binocular images.

Abstract: The invention relates to a method and an optical transmission system for compensation of dispersion in optical transmission lines in which dispersion compensation fibers are applied, with the dispersion compensation fibers being arranged at the beginning as well as at the end of the line segments of the optical fibers forming the transmission line. The signal distortions due to non-linear effects are reduced by making use of the recognition that non-linearities should only occur at as small as possible an accumulated dispersion. This is obtained by an unequal division of the dispersion compensation fiber applied for the compensation of the dispersion of the optical fiber, with the part of the dispersion compensation fiber attached at the beginning of a line segment being directly connected to the optical fiber and having an accumulated dispersion which is smaller as to amount than the accumulated dispersion of the part of the dispersion compensation fiber attached at the end of the optical fiber.

Abstract: A method for measuring the flow rate of a liquid, particularly of blood, in which the frequency shift of a laser beam reflected from the liquid is determined according to the optical Doppler effect. This method and the apparatus provided for its implementation are designed so as to enable reliable measurement of the flow rate of the flowing medium which is resolved both spatially and with respect to time. In accordance with the invention at each scanning point a number of N measured values is collected corresponding to the reflected light, N being a whole number equal to or larger than 2; the Doppler shift is calculated from the time variation of the thus measured intensity of the reflected light at the respective scanning points, and the flow rate is determined from the Doppler shift at each point of the scanning pattern.