Method of calibrating interferometer and interferometer using the same

An interferometer, comprising:

• a voltage controller that executes a first step of generating a spectrum interference signal through sweep of a wavelength of light of a wavelength-swept light source by varying, relative to a time, voltage to be applied to the wavelength-swept light source within one period;
• a Fourier transform processor that executes a second step of obtaining a point-spread-function by sampling the spectrum interference signal at equal time intervals on a time axis, and Fourier transforming the sampled spectrum interference signal by multiplying by a first window function;
• a Hilbert transform processor that executes a third step of obtaining a complex analysis signal including frequency information of the light of the wavelength-swept light source through Hilbert transform with inverse Fourier transform by multiplying the point-spread-function by a second window function;
• an unwrapping processor that executes a fourth step of obtaining a variation in a frequency of the light relative to a time within one period at equal time intervals by unwrapping phase information of the complex analysis signal;
• a substitution processor that executes a fifth step of obtaining a correspondence relationship between the variation in the frequency of the light within one period, which is sampled at the equal time intervals, and a variation in the voltage within one period, which is sampled at the equal time intervals;
• the substitution processor executes a sixth step of obtaining correspondence voltage that is obtained when the variation in the frequency of the light within one period is subdivided by using the correspondence relationship between the variation in the voltage and the variation in the frequency of the light obtained in the fifth step;
• and
• the substitution processor executes a seventh step of substituting the voltage to be applied to the wavelength-swept light source in the first step into the correspondence voltage obtained by the sixth step.