Abstract

A high performance magnetooptic head, which generates a bias magnetic field itself, has been developed. It has a moving magnet actuator to drive an objective lens. The moving magnets have two functions. One is to apply a constant magnetic field on the recording medium. The other is to comprise a magnetic circuit for focusing and tracking control. This magnetooptic head is suitable for use in the two-head erase and write method, in which it is not necessary to change the polarity of the bias magnetic field. Moreover, it enables designing a small-sized magnetooptic disk drive, because a bias magnetic field generator is built into the optical head.

© 1988 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. I. Sander, “Digital Magneto-Optic Storage System,” in Technical Digest, Topical Meeting on Optical Data Storage (Optical Society of America, Washington, DC, 1983), paper THA2.
  2. M. Hartmann, “Erasable Magneto-Optical Recording Media,” IEEE Trans. Magn. MAG-20, 1013 (1984).
    [CrossRef]
  3. T. Murakami, K. Taira, M. Mori, “Magnetooptic Erasable Disk Memory with Two Optical Heads,” Appl. Opt. 25, 3986 (1986).
    [CrossRef] [PubMed]
  4. J. Simkin, C. W. Trowbridge, “On the Use of the Total Scalar Potential in the Numerical Solution of Field Problems in Electromagnetics,” Int. J. Num. Methods Eng. 14, 423 (1979).
    [CrossRef]
  5. T. Mizoguchi, I. Sakai, K. Inomata, “Nd-Fe-B-Co-Al Based Parmanent Magnets with Improved Magnetic Properties and Temperature Characteristics,” Appl. Phys. Lett. 48, 1309 (1986).
    [CrossRef]
  6. K. Ichihara, K. Taira, Y. Terashima, S. Shimanuki, N. Yasuda, “Highly Reliable TbCo Film for Erasable Optical Disk Memory,” in Technical Digest, Topical Meeting on Optical Data Storage (Optical Society of America, Washington, DC, 1985), paper WAA2.

1986 (2)

T. Murakami, K. Taira, M. Mori, “Magnetooptic Erasable Disk Memory with Two Optical Heads,” Appl. Opt. 25, 3986 (1986).
[CrossRef] [PubMed]

T. Mizoguchi, I. Sakai, K. Inomata, “Nd-Fe-B-Co-Al Based Parmanent Magnets with Improved Magnetic Properties and Temperature Characteristics,” Appl. Phys. Lett. 48, 1309 (1986).
[CrossRef]

1984 (1)

M. Hartmann, “Erasable Magneto-Optical Recording Media,” IEEE Trans. Magn. MAG-20, 1013 (1984).
[CrossRef]

1979 (1)

J. Simkin, C. W. Trowbridge, “On the Use of the Total Scalar Potential in the Numerical Solution of Field Problems in Electromagnetics,” Int. J. Num. Methods Eng. 14, 423 (1979).
[CrossRef]

Hartmann, M.

M. Hartmann, “Erasable Magneto-Optical Recording Media,” IEEE Trans. Magn. MAG-20, 1013 (1984).
[CrossRef]

Ichihara, K.

K. Ichihara, K. Taira, Y. Terashima, S. Shimanuki, N. Yasuda, “Highly Reliable TbCo Film for Erasable Optical Disk Memory,” in Technical Digest, Topical Meeting on Optical Data Storage (Optical Society of America, Washington, DC, 1985), paper WAA2.

Inomata, K.

T. Mizoguchi, I. Sakai, K. Inomata, “Nd-Fe-B-Co-Al Based Parmanent Magnets with Improved Magnetic Properties and Temperature Characteristics,” Appl. Phys. Lett. 48, 1309 (1986).
[CrossRef]

Mizoguchi, T.

T. Mizoguchi, I. Sakai, K. Inomata, “Nd-Fe-B-Co-Al Based Parmanent Magnets with Improved Magnetic Properties and Temperature Characteristics,” Appl. Phys. Lett. 48, 1309 (1986).
[CrossRef]

Mori, M.

Murakami, T.

Sakai, I.

T. Mizoguchi, I. Sakai, K. Inomata, “Nd-Fe-B-Co-Al Based Parmanent Magnets with Improved Magnetic Properties and Temperature Characteristics,” Appl. Phys. Lett. 48, 1309 (1986).
[CrossRef]

Sander, I.

I. Sander, “Digital Magneto-Optic Storage System,” in Technical Digest, Topical Meeting on Optical Data Storage (Optical Society of America, Washington, DC, 1983), paper THA2.

Shimanuki, S.

K. Ichihara, K. Taira, Y. Terashima, S. Shimanuki, N. Yasuda, “Highly Reliable TbCo Film for Erasable Optical Disk Memory,” in Technical Digest, Topical Meeting on Optical Data Storage (Optical Society of America, Washington, DC, 1985), paper WAA2.

Simkin, J.

J. Simkin, C. W. Trowbridge, “On the Use of the Total Scalar Potential in the Numerical Solution of Field Problems in Electromagnetics,” Int. J. Num. Methods Eng. 14, 423 (1979).
[CrossRef]

Taira, K.

T. Murakami, K. Taira, M. Mori, “Magnetooptic Erasable Disk Memory with Two Optical Heads,” Appl. Opt. 25, 3986 (1986).
[CrossRef] [PubMed]

K. Ichihara, K. Taira, Y. Terashima, S. Shimanuki, N. Yasuda, “Highly Reliable TbCo Film for Erasable Optical Disk Memory,” in Technical Digest, Topical Meeting on Optical Data Storage (Optical Society of America, Washington, DC, 1985), paper WAA2.

Terashima, Y.

K. Ichihara, K. Taira, Y. Terashima, S. Shimanuki, N. Yasuda, “Highly Reliable TbCo Film for Erasable Optical Disk Memory,” in Technical Digest, Topical Meeting on Optical Data Storage (Optical Society of America, Washington, DC, 1985), paper WAA2.

Trowbridge, C. W.

J. Simkin, C. W. Trowbridge, “On the Use of the Total Scalar Potential in the Numerical Solution of Field Problems in Electromagnetics,” Int. J. Num. Methods Eng. 14, 423 (1979).
[CrossRef]

Yasuda, N.

K. Ichihara, K. Taira, Y. Terashima, S. Shimanuki, N. Yasuda, “Highly Reliable TbCo Film for Erasable Optical Disk Memory,” in Technical Digest, Topical Meeting on Optical Data Storage (Optical Society of America, Washington, DC, 1985), paper WAA2.

Appl. Opt. (1)

Appl. Phys. Lett. (1)

T. Mizoguchi, I. Sakai, K. Inomata, “Nd-Fe-B-Co-Al Based Parmanent Magnets with Improved Magnetic Properties and Temperature Characteristics,” Appl. Phys. Lett. 48, 1309 (1986).
[CrossRef]

IEEE Trans. Magn. (1)

M. Hartmann, “Erasable Magneto-Optical Recording Media,” IEEE Trans. Magn. MAG-20, 1013 (1984).
[CrossRef]

Int. J. Num. Methods Eng. (1)

J. Simkin, C. W. Trowbridge, “On the Use of the Total Scalar Potential in the Numerical Solution of Field Problems in Electromagnetics,” Int. J. Num. Methods Eng. 14, 423 (1979).
[CrossRef]

Other (2)

I. Sander, “Digital Magneto-Optic Storage System,” in Technical Digest, Topical Meeting on Optical Data Storage (Optical Society of America, Washington, DC, 1983), paper THA2.

K. Ichihara, K. Taira, Y. Terashima, S. Shimanuki, N. Yasuda, “Highly Reliable TbCo Film for Erasable Optical Disk Memory,” in Technical Digest, Topical Meeting on Optical Data Storage (Optical Society of America, Washington, DC, 1985), paper WAA2.

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (14)

Fig. 1
Fig. 1

Moving magnet actuator structure.

Fig. 2
Fig. 2

B–H curve for the NdFeBCoAl permanent magnet.

Fig. 3
Fig. 3

B–H curve for pure iron.

Fig. 4
Fig. 4

Modeling for magnetic field calculation.

Fig. 5
Fig. 5

Calculated and measured magnetic field distributions on a recording medium plane and projected positions for the magnets.

Fig. 6
Fig. 6

Calculated and measured magnetic field distributions on a driving coil plane and coil positions.

Fig. 7
Fig. 7

Actuator transfer characteristics (focus direction).

Fig. 8
Fig. 8

Actuator transfer characteristics (radial direction).

Fig. 9
Fig. 9

MO head optical system: L.D. (laser diode); C.L. (collimator lens); P. (prism); B.S. (beam splitter); O.L. (objective lens); L (lens); P.B.S. (polarized beam splitter); Cy.L. (cylindrical lens); P.D. (photodetector); P.M. (permanent magnet).

Fig. 10
Fig. 10

MO head picture.

Fig. 11
Fig. 11

1-MHz readout signal.

Fig. 12
Fig. 12

Readout signal spectrum.

Fig. 13
Fig. 13

Experiment to show moving magnet MO head advantage.

Fig. 14
Fig. 14

Comparison between mean pulse width at different disk positions.

Tables (2)

Tables Icon

Table I Calculated and Measured Magnetic Field Intensities at Specific Positions

Tables Icon

Table II Moving Magnet Actuator Characteristics

Metrics