公开(公告)号：JP2001110082A

公开(公告)日：2001-04-20

申请号：JP28311399

申请日：1999-10-04

Applicant: SONY CORP

Inventor： TOYODA KIYOSHI

IPC: G11B7/135

Abstract: PROBLEM TO BE SOLVED: To prevent a stray light that is caused when the light transmitted through a light separating means is reflected on the light projection plane of the light separating means from being generated and to secure the stable operations of an optical pickup and an optical disk device. SOLUTION: A reflection preventing treatment is applied on a light projection plane of a light separating means where the light beam that is emitted from a light source and transmitted through the light separating means is projected.

公开(公告)号：JPH09288838A

公开(公告)日：1997-11-04

申请号：JP21645096

申请日：1996-08-16

Applicant: SONY CORP

Inventor： MATSUO NORIMASA ,  YUMA YOSHITO ,  TOYODA KIYOSHI ,  IKEDA NAOTO ,  NISHI NORIAKI ,  UEDA MITSUNORI ,  SAITO KIMIHIRO ,  MORIMOTO TADASHI

IPC: G11B7/125 ,  G11B7/13 ,  G11B7/135 ,  H01L31/10 ,  H01S5/00 ,  H01S3/18

Abstract: PROBLEM TO BE SOLVED: To provide the light emitting and receiving elements in small size at low cost, equipped with a monitoring photodetector for detecting a light emitting quantity of a laser diode, and to provide the optical pickup and an optical disk device, utilizing these elements. SOLUTION: A prism 18 having an optical path branching surface 18a for reflecting laser light emitted from the laser diode 17 to an optical disk is formed with a part on the side of a semiconductor substrate 15 from an area required for reflecting the laser light as a chamfered part 18b. A light beam emitted from the laser diode 17 and reflected by the chamfered part 18b is received by the monitoring photodetector 27 formed on the surface of the semiconductor substrate 15.

公开(公告)号：JPH09204685A

公开(公告)日：1997-08-05

申请号：JP30657696

申请日：1996-11-18

Applicant: SONY CORP

Inventor： TOYODA KIYOSHI ,  NISHI NORIAKI ,  SAITO KIMIHIRO

IPC: G11B11/10 ,  G11B7/135 ,  G11B11/105

Abstract: PROBLEM TO BE SOLVED: To suppress the jitter of a detection signal and control the tracking accurately by a method wherein the axis of a light beam entering a light converging means is so inclined as to cancel the astigmatism given to the light beam. SOLUTION: A light beam emitted from a semiconductor laser device 11 is applied to a polarization beam splitter 13 through a grating 12. The grating 12 is composed of a parallel glass plate 22 which is an inclined parallel plate and a diffraction grating 24 which are housed and fixed in a holder 23. By diffracting the light beam emitted from the semiconductor laser device 11, at least three diffraction beams, i.e., a 0 degree diffraction beam, a +1 degree diffraction beam and a -1 diffraction beam, are generated. In an optical pickup 10, by suppressing the astigmatism of a light beam applied to a magneto-optical disc, the generation of the jitter harmful to a detected magneto-optical signal can be effectively avoided without deteriorating a tracking error signal.

公开(公告)号：JPH06131730A

公开(公告)日：1994-05-13

申请号：JP27615092

申请日：1992-10-14

Applicant: SONY CORP

Inventor： TOYODA KIYOSHI ,  SAITO KIMIHIRO

IPC: G11B7/09 ,  G11B7/135 ,  G11B11/10 ,  G11B11/105

Abstract: PURPOSE:To obtain a device small in size and light in weight integrally forming photodetectors for a focusing error signal, a tracking error signal and a magneto-optical signal by arranging six photodetectors on a specified position to an optical axis. CONSTITUTION:Photodetectors 7d, 7c and 7e, 7f are divided by lines x=-1/2Q and 1/2Q bisecting the areas in which spots 51 and 50, 50 and 52 intersetct and are arranged in the areas where the spots 51, 50 and 52, 50 are intersected. Here, Q is a pitch by normalizing the radius of aperture of an objective lens to 1. In such a constitution, by subtracting the sum of the light intensities of the detectors 7f and 7d from the sum of the light intensities of the detectors 7c and 7e, the out-of-focus is detected by means of an RFD method. Detectors 7a and 7b are arranged so as to be symmetric with an x axis, to intersect the spots 53, 54 and not to intersect the spots 51, 52. Consequently, the detectors are integrated.

公开(公告)号：JPH06119675A

公开(公告)日：1994-04-28

申请号：JP26611992

申请日：1992-10-05

Applicant: SONY CORP

Inventor： SAITO KIMIHIRO ,  TOYODA KIYOSHI

IPC: G11B7/135 ,  G11B11/10 ,  G11B11/105

Abstract: PURPOSE:To miniaturize a device and to reduce the positional deviation among parts by unification to improve the reliability by constituting a semiconductor laser, two beam splitters, and photodetectors on a substrate as one body. CONSTITUTION:The laser light from a semiconductor laser 1 is reflected by a polarizing separation film 105 for light branching of a beam splitter 2 of an optical path branching means and is thrown to a recording medium 70, and the reflected light from this medium 70 is transmitted through the film 105. When this transmitted light is made incident on a beam splitter 3 of a polarizing means, the reflected light is separated into p-polarized light and s-polarized light and they are made incident on photodetectors 7 and 8 respectively because the intersection between the junction face of the beam splitter 3 and the reflection or transmission face of the beam splitter 3 and the line connecting the light emission point of a laser 4 and the spot center of the reflection face of a beam splitter 2 due to the laser are inclined at 45 deg.. By this constitution, the laser 1, two beam splitters 2 and 3, and photodetectors 7 and 8 are unified on the substrate to miniaturize the optical head device, and the positional deviation among parts is reduced to improve the reliability.

公开(公告)号：JPH04219655A

公开(公告)日：1992-08-10

申请号：JP7393191

申请日：1991-03-13

Applicant: SONY CORP

Inventor： FUJITA GORO ,  IWAASA SHIYOUJI ,  TOYODA KIYOSHI ,  KASHIWAGI HIROSHI

IPC: G11B5/02 ,  G11B11/10 ,  G11B11/105

Abstract: PURPOSE:To accurately control the position of a head even for an magneto- optical disk having an area different in reflectivity. CONSTITUTION:A gap sensor consisting of a light emitting element 5 and light receiving elements 6 and 7 is arrayed along the track direction of the magneto- optical disk. Thus, the received light quantity of the light receiving elements is prevented from generating an unbalance at the boundary part of the areas of the magneto-optical disk different in reflectivity.

公开(公告)号：JPH03152728A

公开(公告)日：1991-06-28

申请号：JP29305989

申请日：1989-11-09

Applicant: SONY CORP

Inventor： TOYODA KIYOSHI ,  NODA TOYOKAZU

IPC: G11B7/00 ,  G11B7/0033 ,  G11B7/09 ,  G11B7/135

Abstract: PURPOSE:To easily set the value of a minimum recording trace pitch to a desired value by making an angle of a linear lattice part in a light beam scanning detection means variable to a direction orthogonal to a direction of lattice extension with respective to a line scanning direction of a 2nd light beam. CONSTITUTION:The recorder is provided with a card support 11, a light beam incidence control section, a recording signal transmission section 60, and a light beam driving means modulated based on a recording information to scan a 1st light beam made incident in an optical card in a prescribed direction with respect to the optical card and to write the recording information signal onto the optical card. In such a case, an angle of a linear lattice section 52 of an optical beam scanning detection means 50 to a 2nd light beam line scanning direction orthogonal to a direction of the lattice extension is varied to change the pitch in the 2nd light beam line scanning direction. Thus, the value of a minimum recording trace pitch in the write of the recording information signal with respect to the optical card is set to a desired value with very easily and high accuracy.

公开(公告)号：JPH02179935A

公开(公告)日：1990-07-12

申请号：JP33149988

申请日：1988-12-29

Applicant: SONY CORP

Inventor： TOYODA KIYOSHI ,  SHINO KUNINORI

IPC: G11B7/00 ,  G11B7/0033 ,  G11B7/0045 ,  G11B7/125

Abstract: PURPOSE:To make constant the change of the length and width of a recording bit caused by the fluctuation of a moving speed by controlling the output of optical beams from a recording optical beam generating source according to the detection output of the relative recording speed between an optical card and the optical beams. CONSTITUTION:An optical card recording device is provided with a detecting means 3, which detects the relative recording speed between an optical card 1 and the optical beams, and control means 31 to 35, which control the output of the optical beams from an optical beam generating source 4 according to the output of the detecting means 3. When the relative recording speed is increased, optical beam power from the optical beam generating source 4 is increased, and when the relative recording speed is decreased, the optical beam power from the optical beam generating source 4 is decreased. Thus, the bit at constant magnitude can be formed even when the speed fluctuates.

公开(公告)号：JPH02173936A

公开(公告)日：1990-07-05

申请号：JP32845288

申请日：1988-12-26

Applicant: SONY CORP

Inventor： TOYODA KIYOSHI ,  NODA TOYOKAZU

IPC: G11B7/00 ,  G11B7/0033 ,  G11B7/08

Abstract: PURPOSE:To adjust an azimuth without recording onto a card and to minimize an azimuth error after the adjustment by providing photodetectors that monitor the return light from a reference card respectively for a recording optical system and for a reproducing optical system and adjusting the azimuth of both of these optical systems independently. CONSTITUTION:The photodetectors 66 and 60 that monitor the return light from the reference card recorded the prescribed pattern at its reference edge are provided on the recording optical system 12 and the reproducing optical system 14, respectively. The azimuth adjustments of the recording optical system 12 and the reproducing optical system 14are carried out independently. The azimuth adjustment of the reproducing optical system 14 is carried out as conventional. The azimuth adjustment of the recording optical system 12 is carried out as follows: the photodetector 66 is provided and a laser optical source 20 is caused to emit light by a low DC power, the reflected light from the reference card 10 is detected by the photodetector 66 and the azimuth adjustment is carried out by watching the detected output wave form by a monitor 72. Thereby, an azimuth error is minimized. The azimuth adjustment of the recording optical system is carried out without actually recording onto the card.

公开(公告)号：JPH02157641A

公开(公告)日：1990-06-18

申请号：JP31124188

申请日：1988-12-09

Applicant: SONY CORP

Inventor： OKI YUTAKA ,  TOYODA KIYOSHI

IPC: G01N21/55 ,  G11B7/26

Abstract: PURPOSE:To accurately measure the reflectance of the recording layer of the optical recording medium by making the spot of a light beam which is conducted from the surface part of a transparent substrate to a photodetector larger than the spot of a light beam which is conducted from the recording layer to the photodetector. CONSTITUTION:The spot SL1 of the light beam L1 which is conducted from the surface part of the transparent substrate 11 of the recording medium 10 to the light receiving surface 7a of the photodetector 7 is made larger than the spot SL2 of the light beam L2 which is conducted from the recording layer 12 to the light receiving surface 7a of the photodetector 7. Since the light beams L1 and L2 are conducted so that the respective spots SL1 and SL2 formed on the light receiving surface 7a of the photodetector 7 may be made different, the interference between the respective light beams L1 and L2 can be reduced. Therefore, the large error of the measured result caused by the interference between the respective light beams is evaded and the reflectance R2 of the recording layer of the optical recording medium is accurately measured.