Abstract: An optical measuring device (10) for detecting the coloring of test fields of a test strip (12), which is to be wetted with a liquid for detecting substances in said liquid, whereupon the reflectivity of the test fields changes depending on the concentrations of the substances to be detected, comprising: a measuring plane (14) wherein said test strip (12) is to be placed; an illumination device (16) for illuminating the measuring plane (14); a planar image sensor (36); an optical system for imaging said measuring plane (14) onto the image sensor (36); and an electronic evaluation unit (52) for evaluation of the signals detected by said image sensor (36), said illumination device (16) comprises light sources (18, 20, 22) or other means of different colors which serve to alternatively illuminate said measuring plane (14) in different colors, wherein said electronic evaluation unit (52) detects the coloring of the test fields from the images obtained under different color illuminations.

Abstract: A method for the end-side welding of at least two metal sheets disposed on one another in sections, includes selecting welding parameters such that, in the metal sheets to be connected, at least one of which is composed of a high-strength steel, a temperature with which the high-strength steel of the at least one metal sheet is tempered is generated at least in direct vicinity of an end-side weld seam. In addition, through a suitable selection of the welding parameters, a weld pool volume forming the weld seam is generated at an end side of the metal sheets. The weld pool volume has a width greater than the width of the end side of the metal sheets. Therefore, an undercut can be generated between the outer sides of the metal sheets and the weld seam. A form-locking connection can thereby be generated between the metal sheets and the weld seam.

Abstract: An optical measuring device (10) for detecting the coloring of test fields of a test strip (12), which is to be wetted with a liquid for detecting substances in said liquid, whereupon the reflectivity of the test fields changes depending on the concentrations of the substances to be detected, comprising: a measuring plane (14) wherein said test strip (12) is to be placed; an illumination device (16) for illuminating the measuring plane (14); a planar image sensor (36); an optical system for imaging said measuring plane (14) onto the image sensor (36); and an electronic evaluation unit (52) for evaluation of the signals detected by said image sensor (36), said illumination device (16) comprises light sources (18, 20, 22) or other means of different colors which serve to alternatively illuminate said measuring plane (14) in different colors, wherein said electronic evaluation unit (52) detects the coloring of the test fields from the images obtained under different color illuminations.