专利快速检索-快速检索全球专利，免费商用专利数据库-IPRDB

1. 发明专利

JPH04177678A DISK DRIVER 失效
公开(公告)号：JPH04177678A
公开(公告)日：1992-06-24
申请号：JP30578490
申请日：1990-11-09
申请人： MITSUBISHI ELECTRIC CORP , TEAC CORP
发明人： YOSHIMOTO KYOSUKE , NAKAJIMA YOSHIKI , KOYANAGI KIMIYUKI , ITO OSAMU , MASHITA TSUGUAKI , ONDA HIROYUKI , KOBAYASHI YUTAKA , YAMANA KOJI
IPC分类号： G11B21/08 , G11B7/085
摘要： PURPOSE:To always move detecting means in an optimum state by measuring a moving time of the detecting means by measuring means, and forming a voltage waveform to be applied to driving means based on the measured result of the measuring means by driving voltage generating means. CONSTITUTION:A time t1 from a starting time t0 of a jump command of a predetermined voltage to a time of reaching the intermediate position of the track (time until a tracking error signal zero-crosses through a comparator) is measured. A voltage is so set that the t1 falls within + or - T. When it falls within a predetermined time width, a detecting time T2 is provided after a brake pulse is finished, a tracking error signal is extracted, and a brake pulse voltage is varied each by one stage so as to fall within a predetermined range d1. The range of the error amount is set by the amplitude of the error signal, and the amplitude is extracted from the jump starting time, and measured. An accelerating/decelerating voltage value is obtained, a parameter is decided, and stored in a memory of a controller 3. Then, a jumping operation is rapidly and stably conducted based on the memory.

2. 发明专利

JPH0589492A FOCUS SERVO CIRCUIT 失效
公开(公告)号：JPH0589492A
公开(公告)日：1993-04-09
申请号：JP24724291
申请日：1991-09-26
申请人： TEAC CORP , MITSUBISHI ELECTRIC CORP
发明人： MORITA TSUTOMU , ENAMI KATSUYA , ONDA HIROYUKI , NAKAJIMA YOSHIKI , YOSHIMOTO KYOSUKE , ITO OSAMU
IPC分类号： G11B7/00 , G11B7/005 , G11B7/085 , G11B7/09
摘要： PURPOSE:To eliminate the influence of the variation of projected light and dust, etc., on a disk, and to improve the reliability of servo control by inhibiting focus servo control when a sum signal level is below a threshold set from the average value of the sum signal level. CONSTITUTION:The header part of a rotating optical disk 6 is detected periodically by a header part detection circuit 25 on the basis of the level change of a sum signal Y inputted there, and this detection output is digital- converted by an A/D converter 26, and is inputted to a control part 24. The control part 24 measures the sum signal plural times at different timing by a signal related to this header part, and each time, it compares the sizes of the measured sum signal level and the threshold set from the average value of the sum signal level of plural times by the control part 24 with each other, and decides whether the variation of the sum signal level is temporary or not. Accordingly, out-of-focus servo due to the fall of the intensity of reflected light caused by the temporary change of the reflectivity of a disk and the intensity of emitted light of a diode or the dust or a flaw on the disk is never detected.

3. 发明专利

JPH04195732A OFFSET SETTING SYSTEM 失效
公开(公告)号：JPH04195732A
公开(公告)日：1992-07-15
申请号：JP32390090
申请日：1990-11-26
申请人： TEAC CORP , MITSUBISHI ELECTRIC CORP
发明人： MASHITA TSUGUAKI , ONDA HIROYUKI , MURATA HIDEHIKO , YAMANA KOJI , YOSHIMOTO KYOSUKE , NAKAJIMA YOSHIKI , ITO OSAMU , KOYANAGI KIMIYUKI
IPC分类号： G11B7/085 , G11B7/095
摘要： PURPOSE:To accurately conduct the access of a track and regeneration of data by minimizing the beam diameter of light beam projected on a disc in the radial direction at the time of accessing the track and in the direction of the track at the time of regenerating data. CONSTITUTION:A controller 25 gives a regeneration control signal SR commanding the regeneration of data and an access control signal SA commanding the access of a track separately to a data regeneration circuit 26 and an access operation control circuit 27 and and offset signal SOFF commanding an offset value is given to a servo circuit 21. Further, the controller measures a signal level related to a difference between the distance of a lens from a disc corresponding to a moving signal and an actual focusing distance both at the time of the access of the track and at the time of the regeneration of data to give the measured signal level as offset value to the moving signal. Therefore, the beam diameter of light beam is minimized in the radial direction at the time of the access of the track and in the direction of the track at the time of the regeneration of data. Thus, the access of the track and the regeneration of data become accurate.

4. 发明专利

JPH0676306A OPTICAL DISK DEVICE 失效
公开(公告)号：JPH0676306A
公开(公告)日：1994-03-18
申请号：JP19155691
申请日：1991-07-31
申请人： TEAC CORP , MITSUBISHI ELECTRIC CORP
发明人： ONDA HIROYUKI , YAMANA KOJI , KOBAYASHI YUTAKA , MASHITA TSUGUAKI , YOSHIMOTO KYOSUKE , NAKAJIMA YOSHIKI , WATANABE SEIO
IPC分类号： G11B7/085
摘要： PURPOSE:To stabilize pull-in operation for focusing in spite of variation of detecting sensitivity of a focus error signal. CONSTITUTION:Data in which a distance between a focus error signal and a position of a condenser lens 2 for an optical disk 3 is previously decided is stored in a table 13a. The focus error signal detected by irradiating light to the optical disk 3 is stored in a RAM 9. Data of the table 13a is corrected based on data of the RAM 9, corrected data is stored in a RAM 14. Data of the RAM 14 is given to a speed control circuit 8, an actuator 12 is driven in accordance with data of the RAM 14, the condenser lens 2 is controlled in speed, and the condenser lens is moved toward the optical disk 3 side.

5. 发明专利

JPH04195734A FOCUS SERVO CIRCUIT 失效
公开(公告)号：JPH04195734A
公开(公告)日：1992-07-15
申请号：JP32390290
申请日：1990-11-26
申请人： TEAC CORP , MITSUBISHI ELECTRIC CORP
发明人： MASHITA TSUGUAKI , ONDA HIROYUKI , NAGATA TAKUYA , YOSHIMOTO KYOSUKE , NAKAJIMA YOSHIKI , ITO OSAMU
IPC分类号： G11B7/085 , G11B7/095
摘要： PURPOSE:To improve the reliability of a focus servo circuit by comparing a measured sum signal level and a predetermined level of a total signal measured theretofore and by forbidding a focus servo operation, when the former level is lower than the predetermined level. CONSTITUTION:An apparatus is equipped with a means 25 for periodically measuring the total signal Y-level of the output of a plurality of light detectors 9 for receiving a reflected light from an optical disc 6 and with a means SW1 for forbidding a control operation performing control so that focusing of light projected on the optical disc 6 is obtained. Also, the apparatus is constituted to forbid the control operation for obtaining focusing when the level of the measured sum signal Y is lower than the predetermined level of a total signal measured theretofore. In this manner, even if the light reflectance of the optical disc 6 varies or the light intensity of light beam projected on the optical disc 6 varies, a focus servo deviation signal can be obtained to sharply improve the reliability of the optical disc drive.

6. 发明专利

DE69030017D1 未知
公开(公告)号：DE69030017D1
公开(公告)日：1997-04-10
申请号：DE69030017
申请日：1990-04-13
申请人： MITSUBISHI ELECTRIC CORP
发明人： YOSHITOMO KYOSUKE , ITO OSAMU , KOYANAGI KIMIYUKI , NAKAJIMA YOSHIKI , TAKEDA SHUICHI , SHIMODA KYOJI
IPC分类号： G11B7/09 , G11B7/00 , G11B7/08
摘要： An optical disk drive for recording and reproducing information on an optical disk medium includes a servo circuit for controlling tracking of a light beam on an arbitrary track and a servo circuit for controlling focus of the light beam on the disk surface. The disk surface is divided into a plurality of regions, and calibration values for adjusting the servo circuits are determined in each region. The calibration values are stored in a memory and are used to adjust the servo circuits during tracking on an arbitrary track. The calibration values include tracking offset values, focus offset values, servo deviation threshold values and sensor gain values. A number of techniques are disclosed for automatically determining the calibration values.

7. 发明专利

DE69030017T2 未知
公开(公告)号：DE69030017T2
公开(公告)日：1997-10-09
申请号：DE69030017
申请日：1990-04-13
申请人： MITSUBISHI ELECTRIC CORP
发明人： YOSHITOMO KYOSUKE , ITO OSAMU , KOYANAGI KIMIYUKI , NAKAJIMA YOSHIKI , TAKEDA SHUICHI , SHIMODA KYOJI
IPC分类号： G11B7/09 , G11B7/00 , G11B7/08
摘要： An optical disk drive for recording and reproducing information on an optical disk medium includes a servo circuit for controlling tracking of a light beam on an arbitrary track and a servo circuit for controlling focus of the light beam on the disk surface. The disk surface is divided into a plurality of regions, and calibration values for adjusting the servo circuits are determined in each region. The calibration values are stored in a memory and are used to adjust the servo circuits during tracking on an arbitrary track. The calibration values include tracking offset values, focus offset values, servo deviation threshold values and sensor gain values. A number of techniques are disclosed for automatically determining the calibration values.

8. 发明专利

FR2612328B1 未知
公开(公告)号：FR2612328B1
公开(公告)日：1994-12-16
申请号：FR8803298
申请日：1988-03-14
申请人： MITSUBISHI ELECTRIC CORP
发明人： ITO OSAMU , OGAWA MASAHARU , YOSHIMOTO KYOSUKE , TANAKA KUNIMARO , FURUKAWA TERUO , NAKAJIMA YOSHIKI
IPC分类号： G11B7/007 , G11B7/013 , G11B7/085 , G11B19/04 , G11B19/20 , G11B27/30
摘要： An optical disc having a plurality of information tracks, each information track having a servo field including a pair of wobbled pits and a clock pit. The distance between one of the wobbled pits and the clock pit in each servo field is selected such that the optical disc includes at least three different types of servo field. These differnt types of servo field appear in a predetermined sequence for every one or more contiguous information tracks. A driving apparatus for driving such an optical disc has a direction detecting circuit for detecting the moving velocity of a movable portion of an optical head, and a speed detecting circuit for detecting the relative velocity of the movable portion.

9. 发明专利

JPH06259877A DISK DEVICE 失效
公开(公告)号：JPH06259877A
公开(公告)日：1994-09-16
申请号：JP4801693
申请日：1993-03-09
申请人： MITSUBISHI ELECTRIC CORP
发明人： OGAWA MASAHARU , KOYANAGI KIMIYUKI , NAKAJIMA YOSHIKI
IPC分类号： G11B7/085 , G11B19/02 , G11B19/16 , G11B21/08 , G11B21/10
摘要： PURPOSE:To enable shifting a mode from a first control mode to a third control mode at high speed and stably by constituting so as to switch the mode to the third control mode after switching the mode from the first control mode to a second control mode. CONSTITUTION:The mode of the device is switched from a control mode 1 to a control mode 3 based on a command outputted from a control mode switching command generating means 5. At this time, a state value (x) of the control mode l is detected by a state value detecting means 7 based on an operating control value (y) of the control mode 1. An operation value u2 in the second control mode is decided by an operation value deciding means 2 based on the value of the state value (x). After the finish of the first control mode, the mode is switched to the second control mode for a moment and then, an operation value u3 for the third control is inputted to a control object 6 as an operation value u.

10. 发明专利

JPH0421931A SERVO CIRCUIT FOR OPTICAL DISK DEVICE 失效
公开(公告)号：JPH0421931A
公开(公告)日：1992-01-24
申请号：JP12767690
申请日：1990-05-16
申请人： MITSUBISHI ELECTRIC CORP
发明人： ITO OSAMU , NAKAJIMA YOSHIKI , YOSHIMOTO KYOSUKE , KOYANAGI KIMIYUKI
IPC分类号： G11B7/09
摘要： PURPOSE:To reduce the cost of the servo circuit and to stably control a projecting light state with high accuracy by detecting the peak of a photodetection signal by using two transistors and extinguishing offset by controlling the potential of one transistor. CONSTITUTION:The laser beam of a laser diode 1 is condensed to an optical disk 6 by an optical system, and the reflected beam is condensed onto a bisectional detector 9. The photodetection signal outputted from the detector 9 is differentially amplified with reference voltages Vref1 and Vref2 by differential amplifiers 10 and 11, and output voltage signals V1 and V2 are applied to the bases of transistors 17a and 18a in peak detection circuits 17 and 18. In this case, variable resistors 17f and 18f are controlled and the disordered characteristic of the circuit element is corrected so as to detect the peak of the photodetection signal without offset from differential amplifiers 17i and 18i. Then, an output corresponding to tracking error is applied to an actuator 7 by differential and cumulative amplifiers 12 and 13, division circuit 14, phase compensating circuit 15 and amplifier 16, and a condenser lens 4 is controlled. Thus, light projection can be stably controlled with high accuracy at low cost.

你已经成功收藏专利！

检索式保存成功!

IPRDB

热门服务

关于我们

友情链接

联系方式