A method and device for enhancing the power correction of optical measurements in an optical measurement arrangement, the steps including: providing a light source for producing a light beam; splitting the light beam into two beams; directing a first split light beam through an interrogation area and into an optics separation device; directing the light beams from the optics separation device and a second split light beam representing the intensity of the illumination of the main light beam of the light source into cells of a detector array; measuring and assessing the information obtained in the cells; and using this information to calculate the corrected value for the cells receiving the light beams from the optics separation device in order to adjust the power for the intensity of the light beam of the light source and/or to correct the intensity of the light beams from the interrogation area.