SPECTROPHOTOMETER OPERATING ON DISCRETE WAVE LENGTHS

The invention relates to a spectrophotometer operating at discrete wavelengths comprising means to emit variable, substantially monochromatic radiation for irradiating a sample (10) to be tested, a radiation detector (12) sensing the intensity of the radiation reflected or transmitted by the sample (10) and a signal processing unit connected to the radiation detector (12). The radiation emitting means comprises radiation sources (2) emitting substantially monochromatic radiation of different wavelengths, a holder (1) supporting the radiation sources (2) and an optical arrangement (5,6) for transmitting the radiation emitted by the radiation sources (2) successively towards the sample (10). The optical arrangement may comprise at least one mirror (5) supported rotatably with respect to the holder (1). The spectrophotometer is preferably provided with a control unit (3) to operate the radiation sources (2) corresponding to the angular position of said at least one mirror (5), thereby only that one of the radiation sources (2) is operating the radiation of which is just transmitted by the mirror (5).