A distance measuring device that measures a distance to an object using a round-trip time of light, the distance measuring device comprising: a light emitter including a light source that radiates light to a measurement target range; a solid-state image sensor that includes a plurality of pixels included in a plurality of pixel groups capable of being exposed independently, and causes the plurality of pixels to perform photoelectric conversion of reflected light from the object within an angle of view of radiation light from the light emitter, the plurality of pixels being arranged in a matrix; a light emission and exposure controller that (i) instructs a light emission timing and a light emission period of the light source to the light emitter, (ii) instructs, to each of the plurality of pixel groups in the solid-state image sensor, an exposure timing and an exposure period for obtaining pixel signals of types corresponding to a time difference between the radiation light and the reflected light due to a round-trip time of light, and characterized in that, the light emission and exposure controller further (iii) intermittently exposes the plurality of pixels by exposing each of the plurality of pixel groups at a different exposure time in at least two cyclic exposure periods (S0, S1) corresponding to emission of radiation light and one cyclic exposure period when no radiation light is emitted, said exposure periods being comprised in a cycle period, Tbg, of the light source, that is included in a lighting device receiving power from a commercial AC source, cyclically fluctuating and emitting background light in a fluctuation cycle of background light according to the exposure timing and the exposure period, the pixel signals of the types corresponding to the time difference between the radiation light and the reflected light, and wherein, when a cycle of the exposure period for each of the pixel signals of the plurality of pixel groups in the solid-state image sensor is denoted as Tcyc, and the number of exposure periods within one frame is denoted as Ncyc, Tcyc is approximately 1/n relative to the cycle period Tbg of the light source, a time Tcyc×Ncyc that is necessary for exposure and includes an idle period is approximately m times the cycle period Tbg, n being a natural number greater than or equal to 2, m being a natural number greater than or equal to 1; and, the distance measuring device further comprises; a signal processor that calculates a distance value of the object of which an image is formed by the solid-state image sensor, according to pixel signals of at least two adjacent pixels exposed at the different exposure times for each of the plurality of pixel groups in the solid-state image sensor, the pixel signals corresponding to the time difference. a light emitter including a light source that radiates light to a measurement target range; a solid-state image sensor that includes a plurality of pixels included in a plurality of pixel groups capable of being exposed independently, and causes the plurality of pixels to perform photoelectric conversion of reflected light from the object within an angle of view of radiation light from the light emitter, the plurality of pixels being arranged in a matrix; a light emission and exposure controller that (i) instructs a light emission timing and a light emission period of the light source to the light emitter, (ii) instructs, to each of the plurality of pixel groups in the solid-state image sensor, an exposure timing and an exposure period for obtaining pixel signals of types corresponding to a time difference between the radiation light and the reflected light due to a round-trip time of light, and the light emission and exposure controller further (iii) intermittently exposes the plurality of pixels by exposing each of the plurality of pixel groups at a different exposure time in at least two cyclic exposure periods (S0, S1) corresponding to emission of radiation light and one cyclic exposure period when no radiation light is emitted, said exposure periods being comprised in a cycle period, Tbg, of the light source, that is included in a lighting device receiving power from a commercial AC source, cyclically fluctuating and emitting background light in a fluctuation cycle of background light according to the exposure timing and the exposure period, the pixel signals of the types corresponding to the time difference between the radiation light and the reflected light, and wherein, when a cycle of the exposure period for each of the pixel signals of the plurality of pixel groups in the solid-state image sensor is denoted as Tcyc, and the number of exposure periods within one frame is denoted as Ncyc, Tcyc is approximately 1/n relative to the cycle period Tbg of the light source, a time Tcyc×Ncyc that is necessary for exposure and includes an idle period is approximately m times the cycle period Tbg, n being a natural number greater than or equal to 2, m being a natural number greater than or equal to 1; and, the distance measuring device further comprises; a signal processor that calculates a distance value of the object of which an image is formed by the solid-state image sensor, according to pixel signals of at least two adjacent pixels exposed at the different exposure times for each of the plurality of pixel groups in the solid-state image sensor, the pixel signals corresponding to the time difference.