公开(公告)号：JPH0827178B2

公开(公告)日：1996-03-21

申请号：JP29700492

申请日：1992-11-06

Applicant: IBM JAPAN

Inventor： MORITA TETSUHARU ,  KUNO TEIJI ,  FUKUZAWA TADASHI ,  ISOKI KOICHI ,  NODA HIROSHI

IPC: G01B9/02 ,  G01B11/14 ,  G01D1/02 ,  G11B21/21

公开(公告)号：JPH0887724A

公开(公告)日：1996-04-02

申请号：JP22132394

申请日：1994-09-16

Applicant: IBM JAPAN

Inventor： FUKUZAWA TADASHI ,  KUNO TEIJI ,  WATABE HIROSHI ,  TAKAHASHI YASUYUKI ,  OZAWA KOJI

IPC: G11B5/455 ,  G01B11/14 ,  G02B27/00 ,  G02B27/28 ,  G11B5/60 ,  G11B33/10

Abstract: PURPOSE: To maintain a high measuring accuracy by making a measuring error due to an optical elastic phenomenon minimum by providing the polarization eliminator through which light reaching reflection member and light reflected from reflection parts pass in between optical lens member and the reflection member. CONSTITUTION: When light in a linear polarization state by passing through a polarizer 503 passes through a 1/4λ plate 570, it becomes a circular polarization state and receives multiple interfering actions reflected respectively from surfaces of a glass disk 23 and a head 21. These reflected lights are restored to linear polarization states by passing through again the 1/4λ plate 570. The direction of the linear polarization at this time is a direction rotated by 90 deg. from an original direction, at first, the direction of the linear polarization perpendicular to this paper plane becomes a linear polarized light having the polarization direction horizontal to the paper by passing through the 1/4λplate twice. Then, lights whose polarization directions are rotated by 90 deg. in such a way pass through again ojective lens system 507 to reach finally an optical detecting part 515 via an analyzer 513. Moreover, the polarizer 501 and the analyzer 513 are arranged in a form in which transmission polarization axes of them are orthogonal to each other.

公开(公告)号：JPH0765331A

公开(公告)日：1995-03-10

申请号：JP20530893

申请日：1993-08-19

Applicant: IBM

Inventor： FUKUZAWA TADASHI ,  KUNO TEIJI ,  MORITA TETSUHARU ,  ISOGI KOUICHI

IPC: G11B5/455 ,  G01B11/14 ,  G11B5/60 ,  G11B21/21 ,  G11B33/10

Abstract: PURPOSE: To promptly and accurately measure a floating height of a head by optimizing necessary coefficients of a theoretical formula based on a nonlinear regression algorithm when an interference optical intensity corresponding to the floating height of the head is measured by using a white lamp and a color CCD camera. CONSTITUTION: By using a white lamp, a color CCD camera calculates R, G, and B output vectors (y) corresponding to a floating height of a magnetic head by using mathematical models such as a polynomial coefficient vector (b) showing a slider profile, a floating height vector H, a function f (p, x), etc., and outputs them. In this case, a signal processing part operates similar arithmetic operations based on assumed refraction indices of each color and pseudo-vectors (b) according to the extinction coefficients, and a vector (p) of the function (f) is not adopted as a fixed value but is optimized by a processing of a method of least square according to a nonlinear regression algorithm so that a difference vector e between each output vector as the result of the arithmetic operation and the vector (y) becomes a minimum, and thus, it becomes possible to measure the floating height of the floating head quickly and precisely.

公开(公告)号：JPH06147841A

公开(公告)日：1994-05-27

申请号：JP29700492

申请日：1992-11-06

Applicant: IBM JAPAN

Inventor： MORITA TETSUHARU ,  KUNO TEIJI ,  FUKUZAWA TADASHI ,  ISOGI KOUICHI ,  NODA HIROSHI

IPC: G01B9/02 ,  G01B11/14 ,  G01D1/02 ,  G11B21/21

Abstract: PURPOSE:To provide a floating amount measuring apparatus for head which exhibits high sensitivity through simple structure. CONSTITUTION:Light projected from a white light source 25 is introduced into a gap between a disc 23 and a head 21 where multiple reflection takes place. Light reflected on an opaque body, out of the disc 23 and the head 21, is polarized into at least three wavelength regions and introduced to different optical detecting means 35, 36, 37. An estimating unit 38 estimates floating amount of head from an output of the optical detecting means according to the method of least squares based on a function between disc head gap lengths predetermined for respective wavelength regions and the intensity of reflected light detected through the optical detecting means. Calculation is carried out in real time according to table lookup system or follow-up control system.

公开(公告)号：JPH02179762A

公开(公告)日：1990-07-12

申请号：JP24239889

申请日：1989-09-20

Applicant: IBM

Inventor： MAIKERU FUIRITSUPU GORUDOOSUKI ,  KUNO TEIJI ,  JIYON PIITAA KARIDESU ,  SHIBUYA HIROMI ,  UEDA OSAMU

IPC: B41J2/28 ,  B41J9/38 ,  H01F7/14

Abstract: PURPOSE: To make small an actuator by neutralizing a magnetic flux passing a magnetic pole of a permanent magnet for holding an armature by a magnetic flux generated from an electromagnetic coil while being energized thereby biasing the armature. CONSTITUTION: When a coil 20 is excited, an electromagnetic flux almost equal to a magnetic field of a permanent magnet 18 in the opposite direction to that of the magnetic field of the permanent magnet 18 is generated. As a result, the coil 20 almost neutralizes the magnetic field of the magnet 18 holding an armature 28. The armature 28 comes not to be held by the magnetic field of the permanent magnet 18. The energy stored in a spring 32 and the armature 28 separates the armature 28 from a stator 10, which is converted to a kinetic energy for printing. After printing is finished, the excitation of the coil 20 is stopped, and the armature 28 is caught again by the magnetic flux of the permanent magnet 18 and held at a non-print position on magnetic poles 14, 16. When the current of the coil 20 is inverted in direction, the armature 28 is temporarily attracted to the magnet 18, so that the magnet 18 stably holds the armature 28. A package is thus made small and consumption power is reduced.