Patent ID: 7787046

Claim:
A lens module for a camera or the like, comprising: a two part casing containing a magnet housing, permanent magnet means for providing a magnetic field, a lens holder for supporting a lens, and a coil fixed to an outer surface of the lens holder; the casing having an upper case and a lower case; the magnet housing having an annular shape formed by a round cylindrical outer wall and a round cylindrical inner wall concentric with the outer wall and joined at an upper end by a top wall, the lower end being left open and the axial length of the inner wall being less than that axial length of the outer wall; the permanent magnet means comprises at least one permanent magnet fitted to an inner surface of the outer wall; the lens holder having a through aperture defining an optical axis, the through aperture being arranged to accommodate the lens, the lens holder having an upper end and a lower end, the radially outer surface of the lens holder includes a flange located towards the lower end, the through aperture of the lens holder having a stepped bore such that an upper portion of the bore has a greater diameter than a lower portion, the lens holder being insertable in the magnet housing such that the inner wall of the magnet housing confronts the upper portion of the bore; an upper cushion is fixed to an inner surface of the top wall of the magnet housing and located to prevent direct contact between the upper end of the lens holder and the top wall of the magnet housing, defining a park position for the lens holder; the lens holder being supported by two springs which engage the lower end of the lens holder and the lower case to resiliently support the lens holder for movement along the optical axis and biasing the lens holder upwardly into contact with the upper cushion, the coil sits on an axially upper surface of the flange and is disposed within the magnetic field of the permanent magnet means whereby current passing through the coil generates a magnetic field which reacts with the magnetic field of the permanent magnet means to cause the coil to press downwardly on the flange and move the lens holder against the force of the springs.