OPTICAL CHARACTERISTIC MEASUREMENT DEVICE AND OPTICAL CHARACTERISTIC MEASUREMENT METHOD SUITABLE FOR SPECTRUM MEASUREMENT

A processing unit obtains a first spectrum detected in a first detection area and a first signal intensity detected in a second detection area after the light entering the housing is cut off, and then calculates a first correction spectrum by subtracting a first correction value calculated based on the first signal intensity from each component value of the first spectrum. The processing unit obtains a second spectrum detected in the first detection area and a second signal intensity detected in the second detection area while a cut-off portion is opened, and then calculates a second correction spectrum by subtracting a second correction value calculated based on the second signal intensity from each component value of the second spectrum. The processing unit calculates an output spectrum representing a measurement result by subtracting a corresponding component value of the first correction spectrum from each component value of the second correction spectrum.