Apparatus and method for measuring distance and/or velocity of object

A method executed by a computer in a system including a measurement apparatus that includes

• a light source that emits light whose frequency is modulated in a period including an up-chirp duration in which the frequency increases and a down-chirp duration in which the frequency decreases,
• an interference optical system that splits the light emitted from the light source into reference light and output light and generates interfering light between reflected light resulting from reflection of the output light on an object and the reference light,
• a photodetector that receives the interfering light and outputs a detection signal corresponding to strength of the interfering light, and
• a storage apparatus that stores first correction data for the up-chirp duration and second correction data for the down-chirp duration,
• the method comprising:
• generating a first corrected signal by correcting a part of the detection signal corresponding to the up-chirp duration based on the first correction data and/or a second corrected signal by correcting a part of the detection signal corresponding to the down-chirp duration based on the second correction data;
• and
• generating and outputting measurement data concerning distance and/or velocity based on the first corrected signal and/or the second corrected signal.

A non-transitory computer-readable medium having a program executed by a computer, the computer being configured to control a measurement apparatus,

• wherein the measurement apparatus includes
• a light source that emits light whose frequency is modulated in a period including an up-chirp duration in which the frequency increases and a down-chirp duration in which the frequency decreases,
• an interference optical system that splits the light emitted from the light source into reference light and output light and generates interfering light between reflected light resulting from reflection of the output light on an object and the reference light,
• a photodetector that receives the interfering light and outputs a detection signal corresponding to strength of the interfering light, and
• a storage apparatus that stores first correction data for the up-chirp duration and second correction data for the down-chirp duration,
• the program causing the computer to execute operations comprising:
• generating a first corrected signal by correcting a part of the detection signal corresponding to the up-chirp duration based on the first correction data and/or a second corrected signal by correcting a part of the detection signal corresponding to the down-chirp duration based on the second correction data;
• and
• generating and outputting measurement data concerning distance and/or velocity based on the first corrected signal and/or the second corrected signal.