An image sensor that is configured to capture an image of light from a predetermined depth of a subject , the image sensor comprising: a photoelectric converter that is configured to photoelectrically convert light comprising interference light of light from the subject and reference light, and being characterized by : a discrimination unit that is configured to detect, by locking in, a signal component having an interference frequency in an interference light component corresponding to the predetermined depth from a signal output from the photoelectric converter ; and a floating diffusion unit that is configured to temporarily accumulate an electric charge resulting from the photoelectric conversion by the photoelectric converter , wherein: the discrimination unit comprises: a transfer unit (303, 303-1, 303-2) that is configured to transfer the signal to the floating diffusion unit ; a sampling unit that is configured to sample the electric charge accumulated in the floating diffusion unit at a sampling frequency determined based on the interference frequency and; a filtering unit that is configured to separate a component having a low frequency equal to or less than a predetermined value and a direct current from a signal output from the sampling unit . a photoelectric converter that is configured to photoelectrically convert light comprising interference light of light from the subject and reference light, and being characterized by : a discrimination unit that is configured to detect, by locking in, a signal component having an interference frequency in an interference light component corresponding to the predetermined depth from a signal output from the photoelectric converter ; and a floating diffusion unit that is configured to temporarily accumulate an electric charge resulting from the photoelectric conversion by the photoelectric converter , wherein: a discrimination unit that is configured to detect, by locking in, a signal component having an interference frequency in an interference light component corresponding to the predetermined depth from a signal output from the photoelectric converter ; and a floating diffusion unit that is configured to temporarily accumulate an electric charge resulting from the photoelectric conversion by the photoelectric converter , wherein: the discrimination unit comprises: a transfer unit (303, 303-1, 303-2) that is configured to transfer the signal to the floating diffusion unit ; a sampling unit that is configured to sample the electric charge accumulated in the floating diffusion unit at a sampling frequency determined based on the interference frequency and; a filtering unit that is configured to separate a component having a low frequency equal to or less than a predetermined value and a direct current from a signal output from the sampling unit . a transfer unit (303, 303-1, 303-2) that is configured to transfer the signal to the floating diffusion unit ; a sampling unit that is configured to sample the electric charge accumulated in the floating diffusion unit at a sampling frequency determined based on the interference frequency and; a filtering unit that is configured to separate a component having a low frequency equal to or less than a predetermined value and a direct current from a signal output from the sampling unit . <EOS>