Abstract: A device for the density or colorimetric measurement of a measured object, i.e., a densitometer or colorimeter, comprising a light source for directing measurement light onto an object to be measured, a polarization filter positioned between the light source and the object to be measured, a photoelectric sensor, a second polarization filter positioned between the object to be measured and the sensor, at least one of the polarization filters for electronic control of polarization plane orientation, a measurement lens for directing the measurement light originating from a measurement location of the measured object through the second polarization filter and onto the sensor and a controller for electronically rotating the polarization plane for one of the polarization filters relative to the other by 90°.

Abstract: A device for the photoelectric measuring of an opaque or transparent object to be measured includes a photoelectric sensor (4) and a measuring optics (3) which directs measuring light originating from a measurement field of the object to be measured (6) onto the sensor (4). A control electronic (5) cooperates with the sensor (4) for the processing of the electrical signals produced by the sensor. The sensor (4) includes at least two individually controlled and concentrically arranged partial sensors (41, 42, 43), and the control electronics (5) includes switching means (51) by which the partial sensors (41, 42, 43) can be selectively switched on or off-line. The use of a photoelectric sensor made of or divided into several partial sensors enables a purely electronic and therefore simple and fast selection of different effective measurement field sizes.