<p>An optical receiver section (4) of a photometer (2) includes optical receiver elements (4a) disposed at a position corresponding to short wavelength-side light that is cut by a cut filter (26), wherein outputs from the optical receiver elements (4a) disposed at the position corresponding to the short wavelength-side light that is cut by the cut filter (26) are used as dark current outputs. An operational circuit (6) is provided with a correction circuit (30) that uses the dark current outputs to correct a photometer output from each of the optical receiver elements (4a) disposed at a position corresponding to long wavelength-side light rather than the short wavelength-side light to be cut.</p>
