摘要 |
In a spectrophotometer, light emitted from a light source is processed to provide monochromatic light by a monochromator, and reaches a sector mirror having a chopper function. The sector mirror is rotated by a motor, and a rotational frequency of the motor can be controlled by a controller. By rotation of the sector mirror, monochromatic light is alternately distributed to a sample cell and a reference cell through a mirror. In measuring a wavelength range where a detector having a photomultiplier with a fast response speed is used, the motor is rotated at a high speed, so that time for scanning a wavelength is shortened. In measuring a wavelength range where a detector having lead sulfide with a slow response speed is used, the motor is rotated at a low speed to obtain a sufficiently strong signal intensity. Accordingly, in the spectrophotometer, the analysis time can be shortened, and the sufficiently strong signal can be outputted at the same time.
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