A lens device for capturing an optical image, the lens device comprising: a lens main body that includes a lens mechanism for forming the optical image a drive motor (3c, 4c, 5c, 6a, 7a) for driving the lens mechanism (3, 4, 5, 6, 7), a drive control unit (9, 10, 11, 12, 13) that drive-controls the drive motor (3c, 4c, 5c, 6a, 7a), a central processing unit of the lens main body for outputting a drive control signal to the drive control unit (9, 10, 11, 12, 13), a lens information output unit for outputting characteristic information indicating lens specifications including lens focal length and open diaphragm, and a lens main body information output unit for outputting information for specifying the lens main body as specification information; a network that includes a power supply interface for the lens main body, and a communication interface for the central processing unit of the lens main body; an operation terminal that includes: an allocation unit for recognizing the lens main body based on the information from the lens main body information output unit or the information from the lens information output unit via the network without going through a camera main body, and for allocating the drive control unit (9, 10, 11, 12, 13) corresponding to the lens mechanism (3, 4, 5, 6, 7) of the recognized lens main body; a data unit for outputting a drive control signal to the allocated drive control unit (9, 10, 11, 12, 13); and a central processing unit of the operational terminal that is connected to the central processing unit of the lens main body via the network, and is adapted for exchanging information with the allocation unit, the data unit, and the central processing unit of the lens main body; and the camera main body that includes an imaging element, the camera main body being optically and physically connectable to the lens main body and being provided with no electrical communication and power supply interfaces, wherein the lens main body has, without going through the camera main body, a secured power supply within a range of allowable voltage and allowable current of the power supply interface, and is capable of drive-controlling the drive motor (3c, 4c, 5c, 6a, 7a) of the lens mechanism (3, 4, 5, 6, 7) by the operation terminal via the network. a lens main body that includes a lens mechanism for forming the optical image a drive motor (3c, 4c, 5c, 6a, 7a) for driving the lens mechanism (3, 4, 5, 6, 7), a drive control unit (9, 10, 11, 12, 13) that drive-controls the drive motor (3c, 4c, 5c, 6a, 7a), a central processing unit of the lens main body for outputting a drive control signal to the drive control unit (9, 10, 11, 12, 13), a lens information output unit for outputting characteristic information indicating lens specifications including lens focal length and open diaphragm, and a lens main body information output unit for outputting information for specifying the lens main body as specification information; a network that includes a power supply interface for the lens main body, and a communication interface for the central processing unit of the lens main body; an operation terminal that includes: an allocation unit for recognizing the lens main body based on the information from the lens main body information output unit or the information from the lens information output unit via the network without going through a camera main body, and for allocating the drive control unit (9, 10, 11, 12, 13) corresponding to the lens mechanism (3, 4, 5, 6, 7) of the recognized lens main body; a data unit for outputting a drive control signal to the allocated drive control unit (9, 10, 11, 12, 13); and a central processing unit of the operational terminal that is connected to the central processing unit of the lens main body via the network, and is adapted for exchanging information with the allocation unit, the data unit, and the central processing unit of the lens main body; and the camera main body that includes an imaging element, the camera main body being optically and physically connectable to the lens main body and being provided with no electrical communication and power supply interfaces, wherein the lens main body has, without going through the camera main body, a secured power supply within a range of allowable voltage and allowable current of the power supply interface, and is capable of drive-controlling the drive motor (3c, 4c, 5c, 6a, 7a) of the lens mechanism (3, 4, 5, 6, 7) by the operation terminal via the network.