公开(公告)号：JPH09231601A

公开(公告)日：1997-09-05

申请号：JP5678896

申请日：1996-02-20

Applicant: SONY CORP

Inventor： NISHI NORIAKI ,  SAITO KIMIHIRO ,  MORIMOTO TADASHI ,  UEDA MITSUNORI ,  KUBO TAKESHI ,  MATSUO NORIMASA ,  HORIE KAZUYOSHI ,  SATO YURIKO ,  SHINO KUNINORI

IPC: G02B5/04 ,  G11B7/13 ,  G11B7/135

Abstract: PROBLEM TO BE SOLVED: To make an optical pickup small size and light weight and also high reliable by casting a light beam made to enter a prism from a branching point of an optical path to the light receiving element from a surface formed with a semitransmission film. SOLUTION: The light emitting and receiving elements 21 and the optical pickup 20 using them are formed integrally with the prism 28 by its double refeaction material. As a result, return light from a magnetooptical disk MO is incident on the prism 28 and is splitted, and also these light beams reflected by the semitransmission film 31 formed on the bottom are reflected by the upper surface of the prism 28 based on a difference of refractive index between the double refractive material constituting the prism 28 and the open air. Then, the beams are guided to the bottom surface of the prism 28 and are incident upon 2nd and 3rd photodetectors. Therefore, it is not necessary to provide a total reflection film on the upper surface of the prism 28, and hence miniaturization and reduction in weight are feasible.

公开(公告)号：JPH0969245A

公开(公告)日：1997-03-11

申请号：JP18135196

申请日：1996-06-22

Applicant: SONY CORP

Inventor： NISHI NORIAKI ,  SAITO KIMIHIRO ,  MATSUMOTO SHUICHI ,  HATTORI MASATO ,  MORIMOTO TADASHI ,  UEDA MITSUNORI ,  KUBO TAKESHI ,  MATSUO NORIMASA ,  HORIE KAZUYOSHI ,  SATO YURIKO ,  SHINO KUNINORI

IPC: G11B11/10 ,  G11B11/105

Abstract: PROBLEM TO BE SOLVED: To miniaturize a device and improve detecting accuracy by providing a semiconductor substrate having a photo-detector group and a polarization separating element in an optical pickup. SOLUTION: Light receiving elements PD1-PD3, a light emitting element LD for emitting light rays on a magneto-optical-signal recording medium and a polarization separating element 43 are mounted on a semiconductor substrate 42, and an optical pickup is constituted. The polarization separating element 43 comprises a double-refraction type single body, receives the returning light of the light rays reflected from the magneto-optical recording medium, separates the returning light and guides the light to the specified positions of the light receiving elements PD1, PD2 and PD3. Thus, the returning light reflected from the magneto-optical signal recording medium is securely separated into the direction determined by the optical axis of the double-refraction type material single body. Therefore, the improvement of accuracy and the compact production of the device are made possible.

公开(公告)号：JPH05234298A

公开(公告)日：1993-09-10

申请号：JP3224792

申请日：1992-02-19

Applicant: SONY CORP

Inventor： MORIMOTO TADASHI ,  UCHINO KENJI ,  NOZAKI KAGEHARU

IPC: G11B21/12 ,  G11B21/22

Abstract: PURPOSE:To prevent a magnetic disk and a magnetic head from coming into contact with each other, and to execute magnetic recording with high density by providing a piezoelectric element on a rest part on which the magnetic head is placed, and displacing a displacement enlarging plate in accordance with expansion and contraction of the piezoelectric element. CONSTITUTION:In a rest part 10 provided adjacently to a magnetic disk 1, a piezoelectric element 11 laminated in the radial direction of the disk 1 is arranged. Also, a displacement enlarging plate 12 displaced in the direction vertical to the surface of the disk 1 in accordance with expansion and contraction of the element 11 is provided. At the time of starting recording and reproduction, a sufficient air flow is generated by rotating the disk 1 and setting it to a stationary rotating state, and thereafter, by applying a voltage to an electrode 13 of the element 11, it is expanded in the vertical direction, and a rest position 15 of the plate 12 is set higher than the surface of the disk 1. In such a state, a magnetic head 2 is moved onto the disk 1 from the rest part 10. At the time of stopping, the element 1 is contracted, the rest position 15 of the plate 12 is set lower than the disk 1 and the head 2 is placed thereon. In such a way, a rough texture processing of the disk 1 becomes unnecessary, and high density can be obtained.

公开(公告)号：JPH0428011A

公开(公告)日：1992-01-30

申请号：JP13454390

申请日：1990-05-24

Applicant: SONY CORP

Inventor： MURANO KANJI ,  SEKIYA TETSUO ,  TOYODA JUNICHI ,  MORIMOTO TADASHI

IPC: G11B5/60 ,  G11B21/21

Abstract: PURPOSE:To improve and stabilize electromagnetic conversion efficiency by varying a gap between a magnetic head element and a magnetic recording medium by driving a piezoelectric actuator. CONSTITUTION:This device is comprised of a slider 1 that travels floating over i.e. separating from the magnetic recording medium D, the piezoelectric actuator 2 provided at the slider 1, and the magnetic head element 3 provided at the actuator 2 and in which an operating magnetic gap is provided so as to face with the floating plane 1A side of the slider 1. Since a distance between the magnetic head element 3 and the magnetic recording medium D can be selected at an arbitrary and constant distance by driving the piezoelectric actuator 2, a floating distance can be reduced essentially, which enables a stable operation to be performed. In such a way, it is possible to improve and stabilize the electromagnetic conversion efficiency.

公开(公告)号：JPH02188169A

公开(公告)日：1990-07-24

申请号：JP645789

申请日：1989-01-13

Applicant: SONY CORP

Inventor： MURANO KANJI ,  MORIMOTO TADASHI

IPC: H02N2/00

Abstract: PURPOSE:To improve the efficiency and miniaturize the size of a motor by generating oscillation to a piezoelectric body so that the area of two facing sides of a square in an elastic body will change. CONSTITUTION:An ultrasonic linear motor is equipped with an elastic body 20 and composed of a flat square metal plate. Projected sections 21 to 22 are respectively provided on and under the metal plate, to both sides of which piezoelectric bodies 23 to 24 are stuck for constitution. The above projected pieces 21 to 22 are brought into contact with the driving surface so as to send a moving piece forward by this elastic body 20 and resonance expansion oscillation is caused by applying alternating current to the piezoelectric bodies 23 to 24.