Abstract: In this method, the surface to be investigated is first of all exposed to collimated light and the radiation rejected therefrom supplied to a position-resolving image processing means. Then, a mask is generated on the basis of the image supplied by the image processing means, said mask having masked regions being defined by relatively bright areas of said image and unmasked regions being defined by relatively dark areas of said image. Now, the surface to be investigated is exposed to diffuse light and the radiation rejected therefrom supplied to the image processing means, with only the radiation from the unmasked regions being taken into consideration for analyzing purposes.

Abstract: A method to detect and analyze defects of a sample surface In this method, the surface to be investigated is first of all exposed to collimated light and the radiation rejected therefrom supplied to a position-resolving image processing means. Then, a mask is generated on the basis of the image supplied by the image processing means, said mask having masked regions being defined by relatively bright areas of said image and unmasked regions being defined by relatively dark areas of said image. Now, the surface to be investigated is exposed to diffuse light and the radiation rejected therefrom supplied to the image processing means, with only the radiation from the unmasked regions being taken into consideration for analyzing purposes.

Abstract: A method for determining the time curve of the intensity of radiation present at the location of at least one sample which is being examined. The sample follows a circular path of movement in a sealed sample chamber of a weathering testing device, around a stationary radiation device for producing UW and global radiation. At least one sensor which detects the momentary radiation intensity of the radiation device is provided. The sensor moves together with the at least one sample, and is displaced in relation thereto in relation to the radiation device, for example in the peripheral direction of the path of movement. An electrical signal corresponding to the momentary intensity of the radiation is derived by the sensor at set intervals.