公开(公告)号：WO1996031874A1

公开(公告)日：1996-10-10

申请号：PCT/EP1996001059

申请日：1996-03-13

Applicant: AGFA-GEVAERT AG ,  WEINERT, Volker

Inventor： AGFA-GEVAERT AG

IPC: G11B05/02

CPC classification number: G11B5/02

Abstract: The invention is based on a process for reading magnetically recorded signals from a photographic film provided with a transparent thin magnetic layer. The signals from a magnetic reading head applied to the moving film are pre-amplified and the pre-amplified signals are evaluated. Signals capable of being read from transparent magnetic layers are likely to be at least two hundred times weaker than those from standard layers used for recording audio signals or computer data. The object of the invention is therefore to design a procedure suitable for reading extremely weak magnetic signals. This involves operating the magnetic reading head (2) through the pre-amplifier in short-circuit. This means that the internal resistance Ri of the magnetic head is very high compared to the input resistance Re of the amplifier connected immediately downstream of the magnetic head coil.

Abstract translation: 本发明涉及一种方法，用于从一设置有透明的薄磁性层的照相胶片，其中的按压移动的薄膜磁读取头的信号被前置放大和前置放大信号被评估读取磁存储的信号。 从透明的磁性层可读很可能至少由200比常规层中的用于记录音频或计算机数据的一个因素是较弱的信号。 因此，本发明的目的是提供一种适合于读出极弱的磁信号的过程的形式。 这里，读出磁头（2）由前置放大器（5）在短路操作。 用于操作通过在短路操作中的前置放大器的磁读取头，相比于重新磁头线圈放大器的直接下游的输入电阻磁头的内部电阻R 1是非常大的。

公开(公告)号：WO1995035564A3

公开(公告)日：1995-12-28

申请号：PCT/IB1995000435

申请日：1995-06-06

Applicant: PHILIPS ELECTRONICS N.V. ,  PHILIPS NORDEN AB

Inventor： PHILIPS ELECTRONICS N.V. ,  PHILIPS NORDEN AB ,  VOORMAN, Johannes, Otto ,  POTHAST, Hendrik, Jan ,  WONG-LAM, Ho, Wai

IPC: G11B05/02

公开(公告)号：WO1989012886A1

公开(公告)日：1989-12-28

申请号：PCT/GB1989000668

申请日：1989-06-15

Applicant: THE GOVERNORS OF PAISLEY COLLEGE OF TECHNOLOGY ,  PETTIGREW, Archibald, McGilvray

Inventor： THE GOVERNORS OF PAISLEY COLLEGE OF TECHNOLOGY

IPC: G11B05/02

CPC classification number: G11B5/02

Abstract: There is described a method and apparatus for magnetic recording wherein the signal to be recorded is modified in inverse proportion to the transfer function of the recording process. In addition, the harmonics of the modified signal are subjected to phase advance in relation to their frequency.

Abstract translation: 描述了一种用于磁记录的方法和装置，其中要记录的信号与记录过程的传递函数成反比地被修改。 此外，修正信号的谐波相对于它们的频率进行相位提前。

公开(公告)号：WO1984002602A1

公开(公告)日：1984-07-05

申请号：PCT/JP1983000444

申请日：1983-12-20

Applicant: SONY CORPORATION ,  KANEKO, Masahiko ,  TAMADA, Hitoshi ,  OKAMOTO, Tsutomu ,  YAMADA, Toshiro

Inventor： SONY CORPORATION

IPC: G11B05/02

CPC classification number: G11B11/10504 ,  G11B11/10515 ,  G11B11/10536 ,  G11B11/10589

Abstract: Thermomagnetic optical recording method which can be employed in a photomagnetic disk apparatus using a photomagnetic memory. The surface of a substrate (1) is provided with a recording film by deposition, that is, with a soft magnetic film (2) which is easily magnetized perpendicular to its plane, and in which recording is effected by means of magnetic bubbles. A metal or semi-metal film (3) is laminated onto the film (2) by deposition so that it is directly adjacent thereto, to form a recording medium (4). Then a bias magnetic field is applied to the magnetizable film (2) of the recording medium (4) so that a single magnetic domain is produced over all the surface thereof, and the magnetization thereof is oriented in a direction perpendicular to the plane of the film. Laser beam pulses are applied onto the single magnetic domain to form a cylindrical magnetic domain which is magnetized in the direction opposite to the direction of magnetization of the applied bias magnetic field, to record bit data. This arrangement makes it possible to effect recording by means of a semiconductor laser with an output wavelength which is barely absorbed by the magnetizable film (2) acting as the recording film, e.g., of a long wavelength.

公开(公告)号：EP0171022A3

公开(公告)日：1988-02-03

申请号：EP85109546

申请日：1985-07-30

Applicant: Nippon Gakki Seizo Kabushiki Kaisha

Inventor： Tomisawa, Norio

IPC: H03K05/13 ,  G11B05/02

CPC classification number: H03K5/133 ,  G11B20/10009 ,  G11B20/225 ,  H03H11/265 ,  H03K3/0315 ,  H03K7/06 ,  H03K7/08 ,  H03K2005/00065 ,  H03K2005/00097 ,  H03K2005/00143 ,  H03K2005/00195

Abstract: A signal delay device comprises a CMOS gate circuit (12, 14) having an input terminal (13) to which a binary input signal to be delayed is applied, an output terminal (15) from which a delayed signal is derived and power voltage supply terminals to which operation power voltages are applied. The delay time of the CMOS gate circuit depends upon voltage applied to it and, utilizing this phenomenon, voltage control means (16,18) is provided in a power supplying path for the CMOS gate circuit for controlling voltage applied to the CMOS gate circuit. The signal delay device using the CMOS gate circuit is applied to various circuits including an analog signal delay circuit, a jitter absorption circuit and a fixed head type magnetic tape reproducing device.

公开(公告)号：EP0147773A3

公开(公告)日：1987-09-02

申请号：EP84115730

申请日：1984-12-18

Applicant: SONY CORPORATION

Inventor： Hara, Masaru c/o Sony Kohda Corporation

IPC: G11B05/02 ,  G11B20/02 ,  G11B05/592 ,  G11B05/03

CPC classification number: G11B20/02 ,  G11B20/182

Abstract: A method of making a linearity standard magnetic tape is disclosed which includes the steps of providing a rotary magnetic head (1 to 4) assembly including a pair of magnetic heads (HA, HB) having different azimuth gaps, respectively, and for recording slant tracks (1a, 1b) alternately on a magnetic tape (2), a circuit (6,8,10) for supplying a first pilot signal (f 2 , f 4 ) of low frequency and a linearity standard signal of high frequency (e. g. 1 MHz) to one of the magnetic heads (HB) and a circuit (5, 7, 9) for supplying a second pilot signal (f 1 , f 3 ) of a low frequency and a bias signal of higher frequency (e.g. 9 MHz) than that of the linearity standard signal to the other (HA) of the magnetic heads.

公开(公告)号：EP0110365A3

公开(公告)日：1985-06-19

申请号：EP83111898

申请日：1983-11-28

Applicant: OLYMPUS OPTICAL CO., LTD.

Inventor： Yunoki, Yutaka ,  Kimura, Kenji ,  Kato, Akira ,  Imamura, Tasuo

IPC: G11B05/008 ,  G11B05/52 ,  G11B05/78 ,  G11B05/12 ,  G11B05/02

CPC classification number: G11B5/531 ,  G11B5/0086 ,  G11B5/02 ,  G11B5/1278 ,  G11B5/534 ,  G11B5/538 ,  H04N5/78263

Abstract: A helical scanning type video tape recorder having a rotary cylinder (2) which is slidable on a video tape (3); and a pair of vertical magnetization recording heads (11, 12) mounted on the peripheral wall of the rotary cylinder (2) at prescribed positions; that plane of the vertical magnetization recording heads (11, 12) which faces the magnetic plane of the video tape (3) being provided with a main magnetic pole (33) and auxiliary magnetic pole (31), thereby causing at least one portion (34a) of the recording magnetic flux (Φ) passing from the auxiliary magnetic pole (31) to the main magnetic pole (33) to penetrate the recording magnetic layer (3c) of the video tape (3) at substantially right angles.

Abstract translation: 一种具有可在录像带（3）上滑动的旋转圆柱体（2）的螺旋扫描型录像机; 和一对在预定位置安装在旋转圆筒（2）周壁上的垂直磁化记录头（11,12） 垂直磁化记录头（11,12）的面对录像带（3）的磁性平面的那个平面设置有主磁极（33）和辅助磁极（31），从而导致至少一部分 从辅助磁极（31）通到主磁极（33）的记录磁通量（Φ）的大小（图34a）基本上以直角穿过录像带（3）的记录磁性层（3c）。

公开(公告)号：EP0111312A3

公开(公告)日：1985-01-23

申请号：EP83112352

申请日：1983-12-08

Applicant: HITACHI, LTD.

Inventor： Terada, Toshimichi ,  Kojima, Noboru ,  Shibata, Akira

IPC: G11B05/02 ,  H04N05/783 ,  G11B05/52

CPC classification number: H04N9/8255 ,  H04N5/78263 ,  H04N9/8205 ,  H04N9/8216 ,  H04N9/825

Abstract: 5 A helical scan type magnetic recording/reproducing apparatus in which a magnetic tape (1) is guided helically around a rotary magnetic head assembly (5) over an angular range approximately to 360°. Two magnetic heads (6, 7) are disposed relatively closely to each other at an angle smaller than 180°. The rotary magnetic head assembly (5) performs a single complete rotation for a unit period, for example, one-field period. In recording, video signal of the unit period undergoes time axis compression to be compressed to a period corresponding to a scanning period of the heads during which the magnetic heads (6,7) are in contact with the magnetic tape (1) in each rotation of the head assembly (5) and supplied to the magnetic heads which are so designed that the azimuth angles of the respective gaps differ from each other. The time-axis-compressed video signal is supplied to the two magnetic heads alternately in each of successive rotations of the head assembly (5). Alternatively, the video signal is separated into a luminance signal and a chrominance signal, wherein the former is supplied to one (6') of the magnetic heads while the latter is simultaneously supplied to the other (7'). The record tracks (65, 66, 67, 68) are formed on the magnetic tape in a pattern identical with the track pattern formed by a conventional two-head helical scan type video recorder in which the magnetic heads are disposed in opposition to each other with an angular distance of 180° therebetween and in which no time axis conversion is performed. Thus, the magnetic tape recorded according to the proposal can be reproduced by using the conventional magnetic recording/reproducing apparatus of two-head helical scan type.

公开(公告)号：EP0074796A3

公开(公告)日：1984-01-18

申请号：EP82304724

申请日：1982-09-08

Applicant: SONY CORPORATION

Inventor： Ohira, Takao ,  Niiro, Makoto ,  Okihara, Daijiro

IPC: G11B05/52 ,  G11B15/12 ,  G11B05/02

CPC classification number: G11B15/14

Abstract: A video tape recorder includes a rotary magnetic head drum having a rotating member and a magnetic head (9) mounted on the rotating member, a laser element (LD) mounted on the rotating member, a current source (10) for supplying a constant current to the laser element (LD), a circuit for electrically connecting a coil (8) of the magnetic head (9) in parallel with the laser element (LD), a photoelectric conversion member (PD) fixed in the video tape recorder, and members (12, 15) for optically coupling the laser element (LD) with the photoelectric conversion member (PD).

公开(公告)号：EP0171234A3

公开(公告)日：1987-10-28

申请号：EP85305301

申请日：1985-07-25

Applicant: MINNESOTA MINING AND MANUFACTURING COMPANY

Inventor： Knowd, Michael J. c/o Minnesota Mining and

IPC: G11B05/02 ,  G11B05/008 ,  G11B20/18 ,  G11B20/10

CPC classification number: G11B20/00123 ,  G11B20/00086 ,  G11B2020/10546

Abstract: Circuitry usable in a tamper protected recording system for characterizing audio signals at the time of recording including a filter (10) for selecting a portion of the audio signal, a zero crossing detector (14) to detect zero crossings, a threshold detector (16) to determine when the threshold of the detector is satisfied, a first microprocessor (18) for counting the zero crossing detections for successive time intervals and determining for each of the time intervals whether the threshold was satisfied and a second microprocessor (20) for converting the counts and threshold information into data signals that can be recorded with the audio signal.