| 摘要 |
In the present invention, the measurement light emitted from an object to be measured is incident on a fixed mirror and a movable mirror, thereby forming interfering light between the measurement light reflected from said fixed mirror and the measurement light reflected from said movable mirror. At this point, by moving said movable mirror, a change in the interfering light intensity for the measurement light is obtained and the interferogram of the measurement light is acquired on the basis of the change. At the same time, reference light with a wavelength in a narrow band that is a part of the wavelength band of the measurement light is incident on said fixed mirror and said movable mirror, thereby forming interfering light between the reference light reflected from said fixed mirror and the reference light reflected from said movable mirror. At this point, by moving said movable mirror, the interferogram of said measurement light is corrected on the basis of the amplitude of a change in the interfering light intensity for the reference light and the phase difference between, of said measurement light, the measurement light with the same wavelength as that of said reference light and said reference light The spectrum of said measurement light is obtained on the basis of the corrected interferogram. |
