Of Transducer Assembly Mechanism Patents (Class 369/53.38)
  • Patent number: 6747925
    Abstract: A method for generating a center error signal in an optical storage system, as well as an optical storage system, is disclosed. Through the use of the method and system in accordance with the present invention, a decrease in manufacturing costs is achieved since very precise and expensive mirrors and/or photo detectors are not needed. A first embodiment of the invention includes a method for generating a center error signal in an optical storage system, the optical storage system comprising a tracking coil and an optical pick up unit, the optical pick up unit including a light beam. The method comprises the steps of sensing a voltage by a tracking coil, providing the voltage to a center error generation circuit, generating a center error signal from the center error generation circuit based on the voltage and utilizing the center error signal to center the light beam. A second embodiment of the invention includes an optical storage system.
    Type: Grant
    Filed: November 28, 2001
    Date of Patent: June 8, 2004
    Assignee: ProMOS Technologies Inc.
    Inventor: Kechen Cheng
  • Patent number: 6680609
    Abstract: A method of determining a magnetic track width of a magnetic head. The method begins by obtaining a full track profile of the magnetic head which includes a plurality of signal amplitudes read across a track of a magnetic disk at a plurality of magnetic head positions. An initial magnetic track width value is then determined from the full track profile data. Preferably, this initial value is the magnetic write width which is determined based on the difference between left and right head positions which read half of the maximum signal amplitude. To determine the final magnetic write width, the initial value is adjusted with side reading correction values. The side reading correction values are determined based on left and right side reading “tails” of a bell-shaped signal curve which is formed by the full track profile data when graphed. It is not necessary to obtain the microtrack profile to determine these side reading values.
    Type: Grant
    Filed: July 11, 2002
    Date of Patent: January 20, 2004
    Assignee: International Business Machines Corporation
    Inventors: Peter Cheng-I Fang, Terence Tin-Lok Lam, Zhong-heng Lin
  • Patent number: 6246652
    Abstract: A recording and reproducing or observing apparatus based on a laser beam deflection detection method in which an object has a very small area for reflecting light. A laser beam emitted by a semiconductor laser diode passes through a collimator lens and a stop. The beam passes through the lens and stop and is reflected by a polarization beam splitter and focused by an objective lens onto a surface of a cantilever. Reflected light from the cantilever surface is focused by the lens before being received by a position sensor. Either the incident light or the reflected light passes through an optical path that is substantially 90 degrees relative to the optical axis of the other light.
    Type: Grant
    Filed: December 4, 1998
    Date of Patent: June 12, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Kikukawa, Sumio Hosaka, Hajime Koyanagi, Kimitoshi Etoh