Patent ID: 7563039
Filing Date: 2009-07-21
Classification: F16P

Abstract:
1. Apparatus for monitoring a dangerous zone with an optical system for monitoring a protected field comprising at least two opposing optical units arranged so that the protected field is between them, each optical unit including a picture-taking unit, a processing and switching unit operatively connected with the picture-taking unit for generating a danger signal, and a marking associated with each optical unit, each picture-taking unit being arranged so that the marking on an opposite side of the protected field associated with the optical unit of the other picture-taking unit can be viewed by the first-named picture-taking unit, the processing and switching unit including a comparison unit for comparing a picture taken by a picture-taking unit with a reference picture, each optical unit further including at least one lighting unit for illuminating the oppositely positioned marking associated with the oppositely positioned optical unit, the picture-taking unit, the markings and the lighting units of each optical unit being arranged mutually aligned in or on a common housing, wherein the first and second optical units are identical and are arranged longitudinally reversed, opposite and spaced apart from each other, and wherein the lighting units of the first and second optical units are arranged so that they are within the view of the second and first picture-taking units, respectively, and wherein the picture-taking units of the first and second optical units can be subjected to light from the second and first lighting units, respectively, above and/or below a picture-taking threshold illumination of the respective picture-taking units.