Signal processing device, OCT device, signal processing method, and program

A signal processing method that is executed by an optical coherence tomography (OCT) device including a light source, a light receiver, and an optical system configured to form a sample arm that is an optical path in which light output from the light source travels toward a measurement target and travels from the measurement target toward the light receiver, and a reference arm that is an optical path different from the sample arm, the reference arm being an optical path in which light output from the light source travels toward the light receiver, the signal processing method comprising:

• outputting from the light source a plurality of interference beams in which a light beam that is output from the light source and traces the sample arm and a light beam that is output from the light source and traces the reference arm interfere with each other, the plurality of interference beams each having a different wavelength dispersion characteristic difference between the sample arm and the reference arm traced by the light beams interfering with each other;
• acquiring an output signal output from the light receiver receiving the plurality of interference beams simultaneously and a correction signal obtained by applying wavelength dispersion correction processing to the output signal and repeating processing of extracting a maximum peak signal from the output signal and the correction signal and removing a signal corresponding to the peak signal from each of the output signal and the correction signal;
• extracting a combined signal of the output signal after the peak signal is removed and the peak signal removed from the output signal as an extraction signal indicative of one of a plurality of the interference beams;
• and
• extracting a combined signal of the correction signal after the peak signal is removed and the peak signal removed from said correction signal as an extraction signal indicative of the other one of a plurality of the interference beams.

A non-transitory computer readable medium storing a program that causes an optical coherence tomography (OCT) device, the OCT device including a light source, a light receiver, and an optical system configured to form a sample arm that is an optical path in which light output from the light source travels toward a measurement target and travels from the measurement target toward the light receiver, and a reference arm that is an optical path different from the sample arm, the reference arm being an optical path in which light output from the light source travels toward the light receiver, to execute a signal processing method comprising:

• outputting from the light source a plurality of interference beams in which a light beam that is output from the light source and traces the sample arm and a light beam that is output from the light source and traces the reference arm interfere with each other, the plurality of interference beams each having a different wavelength dispersion characteristic difference between the sample arm and the reference arm traced by the light beams interfering with each other;
• acquiring an output signal output from the light receiver receiving the plurality of interference beams simultaneously and a correction signal obtained by applying wavelength dispersion correction processing to the output signal and repeating processing of extracting a maximum peak signal from the output signal and the correction signal and removing a signal corresponding to the peak signal from each of the output signal and the correction signal;
• extracting a combined signal of the output signal after the peak signal is removed and the peak signal removed from the output signal as an extraction signal indicative of one of a plurality of the interference beams;
• and
• extracting a combined signal of the correction signal after the peak signal is removed and the peak signal removed from said correction signal as an extraction signal indicative of the other one of a plurality of the interference beams.