Measurement method, measurement device, and nontransitory computer-readable medium

A measurement device comprising:

• a semiconductor wavelength-tunable laser configured to output output light in such a way that a wavelength discretely changes with time;
• an interferometer configured to split the output light into measurement light and reference light and generate interference light obtained by combining and interfering scattered light obtained by irradiating a sample with the measurement light, and the reference light;
• a photodetector configured to detect the interference light and converts the interference light into an electrical signal;
• and
• a hardware controller configured to select one of a plurality of sample wavelengths as the wavelength of the output light, perform setting in such a way that the selected one sample wavelength sequentially changes with time, and derive a scattering profile of the sample by performing compressed sensing on the electrical signal obtained for each of the plurality of sample wavelengths,
• wherein the hardware controller controls the semiconductor wavelength-tunable laser to output the output light in such a way that parameters related to the plurality of sample wavelengths satisfy the following Formula (4):
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• (in Formula (4),
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• is a Fourier transform of a sampling mask for the plurality of sample wavelengths, z is a specific depth at which a depth profile is extracted, m is the number of plurality of sample wavelengths, and h is the number of non-zero elements in a vector of a scattering intensity in a depth range for the scattering profile).

A non-transitory computer-readable medium storing a program for causing a computer to execute:

• selecting one of a plurality of sample wavelengths as a wavelength of output light of a semiconductor wavelength-tunable laser, and controlling output of the output light in such a way that the selected one sample wavelength changes discretely and sequentially with time;
• acquiring, for each of the plurality of sample wavelengths, an electrical signal obtained by detecting and converting interference light obtained by combining and interfering scattered light obtained by irradiating a sample with measurement light, and reference light for the measurement light and the reference light obtained by splitting the output light;
• and
• deriving a scattering profile of the sample by performing compressed sensing on the electrical signal obtained for each of the plurality of sample wavelengths,
• wherein in the controlling of the output of the output light, control is performed in such a way that parameters related to the plurality of sample wavelengths satisfy the following Formula (6):
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• 6
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• (in Formula (6),
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• f
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• is a Fourier transform of a sampling mask related to the plurality of sample wavelengths, z is a specific depth at which a depth profile is extracted, m is the number of plurality of sample wavelengths, and h is the number of non-zero elements in a vector of a scattering intensity in a depth range for the scattering profile).