OPTICAL LENS DRIVING DEVICE

PURPOSE:To move an objective lens linearly against a tracking error signal, and also make the titled device small in size and light in weight by fixing a magnetic member to the objective lens so that it can move as one body with the objective lens in the direction almost vertical to an optical axis of the lens, and placing a magnetic field control means through the magnetic member and a gap. CONSTITUTION:A magnetic circuit as indicated with an arrow A is constituted by connecting the first and the second fixed yokes 2, 2' to a permanent magnet 1, and in an air-gap between the first and the second yokes 2, 2', a movable member 5 consisting of a magnetic material is placed so as to be freely movable in the direction as indicated with both arrows B. The first and the second coils 4, 4' are wound and installed to the first and the second fixed yokes 2, 2', respectively, and when they are conducted electrically as shown in the figure, the movable magnetic material 5 moves in one of the directions as indicated with the arrow B, the right direction. When the direction of a current which is made to flow to the first and the second coils 4, 4' is reversed, the movable magnetic material 5 moves in the opposite direction, namely, the left direction.