Patent ID: 7203011

Claim:
A lens device for moving a first lens group and a second lens group in an optical-axis direction, said lens device comprising: a first lens frame for holding said first lens group; a first fixed barrel for movably holding said first lens frame in said optical-axis direction; a first driver incorporated in said first fixed barrel to move said first lens frame in said optical-axis direction; a second lens frame for holding said second lens group; a second fixed barrel for movably holding said second lens frame in said optical-axis direction, said second fixed barrel being joined to said first fixed barrel in series in said optical-axis direction; a second driver incorporated in said second fixed barrel to move said second lens frame in said optical-axis direction; and a lens controller for inputting first and second lens-movement signals, in response to which said first and second lens frames are moved, into said first and second drivers respectively, wherein said first driver comprises: a cylindrical first stator for generating magnetic fields at the inside of said first fixed barrel; a cylindrical first rotor coaxially disposed with said first stator to rotate relative to said first stator in virtue of the magnetic fields generated by said first stator, said first lens frame being disposed in said first rotor so as to make an optical axis of said first lens group coincide with an axis of said first rotor; and a first conversion mechanism for converting a direction of a rotational force of said first rotor into said optical-axis direction to transmit the rotational force to said first lens frame.