SPEKTRALPHOTOMETER ZUR MESSUNG MIT EINER GEGENÜBER AUSSENLICHT OFFENEN MESSZELLE

Spectrophotometer has an evaluation unit (20) which has storage means (22) in which a value for light intensity of the light source (10) is deposited. The evaluation unit, by difference-measurement, determines the light intensity of the switched-on light source and the intensity of switched-off light source at each of the measuring cell that is not closed. The evaluation unit is laid out with a sample, arranged in the measuring beam, to determine by difference measurement of intensity with switched-on source of light and intensity with switched-off source of light, with measuring cell that is not closed. The evaluation unit is laid out to determine by different formation from the intensities and a value for the intensity, reduced by absorption of the measuring beam in the sample.