SPECTROPHOTOMETER

摘要

In order to provide a spectrophotometer, which can detect, by means of output intensity signals obtained by an optical detector, entry of external light at the time of sample cell replacement and the like without providing a door with opening/closing sensor and the like, a spectrophotometer (60) is provided with: an optical detector (12); a light blocking unit (41); a storage unit (34), which stores a light blocking period where light is blocked by means of the light blocking unit (41), and output intensity signals obtained by the optical detector (12) by associating the light blocking period and the output intensity signals with each other; and a control unit (31b), which calculates transmittance or light absorbance on the basis of the output intensity signals in the light blocking period, said output intensity signals having been stored in the storage unit (34), and output intensity signals in a light entry period. The spectrophotometer is characterized in that the storage unit (34) stores a threshold for detecting entry of external light to the optical detector (12), and that the control unit (31c) detects entry of the external light to the optical detector (12) on the basis of the output intensity signals in the light blocking period, and the threshold.