A device for extracting depth information, the device comprising: a projecting unit configured to discontinuously project IR (infrared) light of a predetermined pattern during periods; a camera unit configured to capture images; and a signal processing unit configured to perform depth information extraction and RGB image information extraction using the images captured by the camera unit, and a control unit is configured to control the projecting unit, the camera unit, and the signal processing unit, wherein the control unit is configured to control the projecting unit to project the IR light, to control a period of projecting the IR light according to at least one of required depth resolution and a distance from an object and to adjust the period of projecting the IR light using depth information extracted by the extracting of the depth information by the signal processing unit, wherein the control unit is configured to transmit information on the period of projecting the IR light to the signal processing unit, wherein the signal processing unit is configured to extract depth information using an image captured during a first time interval and extracts RGB image information using an image captured during a second time interval, wherein the first time interval corresponds to the period in which the projecting unit projects the IR light, wherein the second time interval corresponds to a whole period in which the projecting unit does not project the IR light, wherein the control unit is configured to control the shortening or the extension of the period in which the IR light is projected according to a result of a comparison of the distance from the object with a threshold value by the signal processing unit. a projecting unit configured to discontinuously project IR (infrared) light of a predetermined pattern during periods; a camera unit configured to capture images; and a signal processing unit configured to perform depth information extraction and RGB image information extraction using the images captured by the camera unit, and a control unit is configured to control the projecting unit, the camera unit, and the signal processing unit, wherein the control unit is configured to control the projecting unit to project the IR light, to control a period of projecting the IR light according to at least one of required depth resolution and a distance from an object and to adjust the period of projecting the IR light using depth information extracted by the extracting of the depth information by the signal processing unit, wherein the control unit is configured to transmit information on the period of projecting the IR light to the signal processing unit, wherein the signal processing unit is configured to extract depth information using an image captured during a first time interval and extracts RGB image information using an image captured during a second time interval, wherein the first time interval corresponds to the period in which the projecting unit projects the IR light, wherein the second time interval corresponds to a whole period in which the projecting unit does not project the IR light, wherein the control unit is configured to control the shortening or the extension of the period in which the IR light is projected according to a result of a comparison of the distance from the object with a threshold value by the signal processing unit.