An optical interferometric range sensor (10; 100), comprising: a light source (51; 110) configured to emit light with a changing wavelength; a light splitter (54a to 54c; 120; 121) configured to split the light emitted from the light source (51; 110) into a plurality of beams to be incident on a plurality of spots; an interferometer configured to generate, for each of the plurality of beams of the split light incident on a corresponding spot of the plurality of spots, interference light based on measurement light and reference light, the measurement light being light emitted from a sensor head (20; 131a, 131b) to a measurement target (T) and reflected from the measurement target (T), the reference light being light traveling on an optical path at least partially different from an optical path of the measurement light; a light receiver (56a to 56c, 58a to 58c, 71a to 71c, 74a to 74c; 140a to 140c) configured to receive the interference light from the interferometer to convert the interference light to an electric signal; a processor (59, 75; 150) configured to calculate a distance from the sensor head (20; 131a, 131b) to the measurement target (T) based on the electric signal resulting from conversion performed by the light receiver (56a to 56c, 58a to 58c, 71a to 71c, 74a to 74c; 140a to 140c); an identifier configured to identify the sensor head (20; 131a, 131b) based on a beat signal generated by the interferometer ; and a light adjuster configured to adjust an amount of light to be emitted from the sensor head (20; 131a, 131b) to the measurement target (T) based on the sensor head (20; 131a, 131b) identified by the identifier , wherein the beat signal results from a portion of the light emitted from the light source (51; 110) and received by the interferometer being reflected from a component of the interferometer including a reflective surface. a light source (51; 110) configured to emit light with a changing wavelength; a light splitter (54a to 54c; 120; 121) configured to split the light emitted from the light source (51; 110) into a plurality of beams to be incident on a plurality of spots; an interferometer configured to generate, for each of the plurality of beams of the split light incident on a corresponding spot of the plurality of spots, interference light based on measurement light and reference light, the measurement light being light emitted from a sensor head (20; 131a, 131b) to a measurement target (T) and reflected from the measurement target (T), the reference light being light traveling on an optical path at least partially different from an optical path of the measurement light; a light receiver (56a to 56c, 58a to 58c, 71a to 71c, 74a to 74c; 140a to 140c) configured to receive the interference light from the interferometer to convert the interference light to an electric signal; a processor (59, 75; 150) configured to calculate a distance from the sensor head (20; 131a, 131b) to the measurement target (T) based on the electric signal resulting from conversion performed by the light receiver (56a to 56c, 58a to 58c, 71a to 71c, 74a to 74c; 140a to 140c); an identifier configured to identify the sensor head (20; 131a, 131b) based on a beat signal generated by the interferometer ; and a light adjuster configured to adjust an amount of light to be emitted from the sensor head (20; 131a, 131b) to the measurement target (T) based on the sensor head (20; 131a, 131b) identified by the identifier , wherein the beat signal results from a portion of the light emitted from the light source (51; 110) and received by the interferometer being reflected from a component of the interferometer including a reflective surface. <EOS>