CHROMATOGRAPHIC SPECTROPHOTOMETER AND REFERENCE POSITION DETECTION METHOD

摘要

A diffraction lattice in this chromatographic spectrophotometer disperses light that has been generated by a light source into light having a plurality of different wavelengths. A sample cell receives light of any one of the wavelengths among the plurality of wavelengths of the light dispersed by the diffraction lattice. A photodetector detects light transmitting through the sample cell. A reference position detection unit: causes a motor to rotate in a first direction by a first angle until the amount of light received by the photodetector reaches or exceeds a predetermined threshold value, and then causes the motor to rotate by a second angle that is smaller than the first angle after the amount of light received by the photodetector has reached or exceeded the threshold value, and thereby detects a rotation angle of the motor at which a peak amount of light received by the photodetector appears; and detects a reference position corresponding to a reference angle of the diffraction lattice on the basis of the detected rotation angle.