Method for pre-calibrating a spectroscopic measurement device, the measurement device having: • a control unit , • a light source , • a sample holder arranged in the beam path of the light source and defining a measurement location, • a spectral measurement module which has a photosensor with a plurality of organic photodiodes arranged on a substrate and with a temperature sensor , calibration values being determined at the measurement location and reference values being determined in a reference measurement plane in the beam path of the light source , the temperature sensor recording temperature values in the direct vicinity of the organic photodiodes, and the method comprising the following steps: i.) arranging a bright calibration sample having high reflectivity at the measurement location and determining a bright calibration value by measuring a deflected radiation by means of the photosensor ; ii.) arranging a dark calibration sample having low reflectivity at the measurement location and determining a dark calibration value by measuring a deflected radiation by means of the photosensor ; iii.) arranging a bright reference sample having high reflectivity in the reference measurement plane and determining a bright reference value by measuring a deflected radiation by means of the photosensor ; iv.) arranging a dark reference sample having low reflectivity in the reference measurement plane and determining a dark reference value by measuring a deflected radiation by means of the photosensor ; v.) recording a dark current signal when the light source is switched off; vi.) repeating steps i. to v. at different temperatures along a predetermined temperature curve, with the temperature and a bright reference value, a bright calibration value, a dark reference value, a dark calibration value, and a dark current signal being recorded for each temperature value; and vii.) storing the determined calibration and reference values and also the related temperature values in the control unit . • a control unit , • a light source , • a sample holder arranged in the beam path of the light source and defining a measurement location, • a spectral measurement module which has a photosensor with a plurality of organic photodiodes arranged on a substrate and with a temperature sensor , i.) arranging a bright calibration sample having high reflectivity at the measurement location and determining a bright calibration value by measuring a deflected radiation by means of the photosensor ; ii.) arranging a dark calibration sample having low reflectivity at the measurement location and determining a dark calibration value by measuring a deflected radiation by means of the photosensor ; iii.) arranging a bright reference sample having high reflectivity in the reference measurement plane and determining a bright reference value by measuring a deflected radiation by means of the photosensor ; iv.) arranging a dark reference sample having low reflectivity in the reference measurement plane and determining a dark reference value by measuring a deflected radiation by means of the photosensor ; v.) recording a dark current signal when the light source is switched off; vi.) repeating steps i. to v. at different temperatures along a predetermined temperature curve, with the temperature and a bright reference value, a bright calibration value, a dark reference value, a dark calibration value, and a dark current signal being recorded for each temperature value; and vii.) storing the determined calibration and reference values and also the related temperature values in the control unit . <EOS>