JPS63263650A - Recording method for magneto-optical recording and reproducing device - Google Patents

Abstract

PURPOSE:To enable overwriting without executing erasing operation by deciding the direction of an externally impressed magnetic field and whether a clock of recording data is to be delayed or not on the basis of sector information recorded in a data management area. CONSTITUTION:Sector information recorded in the data management area of a magneto-optical recording medium is read out to decide each sector recording method corresponding to the constitution of a file. Then, a preformat part is read out to decide whether the read address is an objective address or not, and in case of a correct address, the recording magnetization polarity is set up in accordance with the decided recording method. Whether the clock is to be delayed or not is decided so that the trailing edge of a recording pulse is positioned on the center of a data cell in accordance with the preceding recording state and the clock is delayed in accordance with necessity. Consequently, the recording state is erased by switching the polarity of an external magnetic field and radiating a recording waveform and then data can be recorded and overwritten only by one head without using an erasing head by successively recording data in a user area.

Description

[Detailed description of the invention] [Industrial field of application] The present invention focuses light such as a laser into a spot with a minute diameter,
The present invention relates to a recording method of an apparatus for recording and reproducing information at high density by irradiating a magneto-optical recording medium.

(Prior art) A schematic diagram of the conventional magneto-optical recording method is shown in Figure 4.
In the figure, numeral 11 represents a data cell in which 1-bit data is recorded, and its period is T. Reference numeral 12 indicates the direction of magnetization of the magneto-optical recording medium, which is currently magnetized downward as an initial state. At this time, it is assumed that all 0s are recorded as data. 13 represents the laser output waveform when recording information, and the higher side of the waveform is the recording power, and the lower side is the reproduction power.

When the magneto-optical recording medium in the state 12 is irradiated with a laser beam shown at 13 and at the same time an external magnetic field is applied in the direction shown by the arrow at 13, a recording power is irradiated as shown at 14. The direction of magnetization is reversed only in that portion, and information is recorded.

15 is a reproduced waveform when the magneto-optical recording medium in the state 14 is reproduced, and the portion where magnetization reversal exists in the data cell is designated as 1. In this case, 1101 is recorded. If you try to record new information at this location, 1
By reversing the direction of the externally applied magnetic field and applying DC erasing power as shown in 6, the initial state shown in 12 is restored, and by performing the operation 13 again, new information can be recorded.

[Problem that the invention seeks to solve]

In this way, in conventional magneto-optical recording and reproducing devices, when newly recording information, the previously recorded information must be erased and then recording must be performed, which eliminates the extra operation of erasing. I need. In other words, it is not possible to carry out overlapping aging, which is done with magnetic disks and the like. As a means to solve this problem, a configuration has been developed that enables long-term aging by using two optical pickups, one for recording only and the other for erasing. It modulates at high speed and continues to irradiate laser light during that time.
A method has been proposed to enable aging. However, since these conventional techniques require two optical pickups, the configuration becomes complicated and the number of parts increases, leading to an increase in cost. Furthermore, the high-speed modulation method of the magnetic field has a limitation in that the recording frequency cannot be increased, which poses a practical problem.

Therefore, the present invention is intended to solve these problems, and its purpose is to provide a recording method that allows overwriting in real time using a single optical pickup that has been conventionally used. There is a particular thing.

[Means for solving problems]

A recording method of a magneto-optical recording/reproducing device according to the present invention is a recording method of a magneto-optical recording/reproducing device that records/reproduces information on a magneto-optical recording medium by narrowing a laser beam to a minute diameter. By reading the sector information recorded in the data management area located above, the information recording method of the sector is determined, and the externally applied magnetic field is switched and recorded in accordance with the information in the data management area. A feature is that overwriting can be performed without requiring an erasing operation by turning on and off the delay of the data pulse.

However, when the cycle of 1-bit data cell is T, the width of the recording data pulse mentioned above is T/2 or less, and the delay time of this recording data pulse is T/2.

[Effect]

According to the above recording method of the present invention, the sector information of the data management area provided on the magneto-optical recording medium is read, and based on this value, it is determined whether or not to delay the direction of the externally applied magnetic field and the clock of the recorded data. By then recording these conditions in a titration manner, information can be recorded in real time using only one optical pickup without requiring an erasing operation.

〔Example〕

Hereinafter, the present invention will be explained in detail based on the drawings.

A schematic diagram of the magneto-optical recording method of the present invention is shown in FIG. 1st
In the figure, 21 represents a data cell in which 1-bit data is recorded, and its period is T. 22 indicates the direction of magnetization of the magneto-optical recording medium, which is currently magnetized upward as an initial state. At this time, it is assumed that all 0s are recorded as data. 23 represents a laser output waveform when recording information. The higher side of this waveform will be called the recording power, and the lower side will be called the reproduction power. As shown in the figure, the trailing edge of the recording pulse is always -4 at the starting point of the data cell, and the pulse width is made shorter than T/2. When the magneto-optical recording medium in the state 22 is irradiated with a laser beam shown at 23 and at the same time an external magnetic field is applied in the direction shown by the arrow at 23, a recording power is irradiated as shown at 24. The direction of magnetization is reversed only in that portion, and information is recorded. 2
5 is a reproduced waveform when the magneto-optical recording medium in state 24 is reproduced, and 1 indicates a portion where magnetization reversal exists in the data cell. In this case, 1101 is recorded. Next, when overwriting this same location, the direction of the externally applied magnetic field is reversed as shown at 26, and the magnetization shown at 27 is irradiated with a recording waveform in which the pulse falls at the center of the data cell. A pattern is formed.

At this time, 24 magnetization patterns are completely erased. In other words, the recorded state indicated by 24 is erased, and a new state indicated by 27 is recorded. 28 is a reproduced waveform when the magneto-optical recording medium in the state 27 is reproduced, and if the portion where magnetization reversal exists in the data cell is 1, then 1011 is recorded. When overwriting further, new information can be recorded by performing the process 23. In this way, when the recording method of the present invention is used, the erasing operation required in conventional magneto-optical recording becomes unnecessary, and recording can be performed in real time.

FIG. 2 shows a schematic diagram of the format of the magneto-optical recording medium used in the present invention. Reference numeral 31 indicates a preformat section in which track addresses, e-sector addresses, etc. are formed in advance as irregular pits on the magneto-optical recording medium, and reference numeral 32 indicates a preformat section for switching the externally applied magnetic field and for switching on/off the delay of recording/reproducing data pulses. The gap 33 is a user data area where user data is recorded. 34 indicates a sector division in a part of the buffer.

35 indicates a data management area of the magneto-optical recording medium. This part records the information recording method for each sector. 1
A track is formed by a plurality of sectors clustered together.

FIG. 3 is a flowchart during recording and reproduction according to the present invention. When recording, the data management area 35 is read at 40 to learn the configuration of the file to be recorded and the corresponding sector recording method. Next, read the preformat section 31 in Figure 2. At 41, determine whether it is the target address or not. If the address is at the correct address, set the polarity at 42 according to the information in the data management area read earlier. , when the previous recording state is in the state 24 in Fig. 1, 2, the clock is delayed at 43 so that the falling edge of the recording pulse is at the center of the data cell, and the direction of the externally applied magnetic field is adjusted appropriately at 44. switch in the direction. In state 27, the clock is not delayed and only the polarity of the magnetic field is switched. This is done between the gear parts 330. After that, 45
The data is recorded in the user area 33. When recording of one file is completed, the sector information in the data management area is finally updated. During reproduction, the polarity of the external magnetic field is not switched, and only the clock delay 43 is performed according to the contents of the sector information. In this way, data can be recorded and reproduced without an erasing operation.

[Effects of the Invention] As described above, according to the present invention, overwriting can be performed on a magneto-optical recording medium using only one optical pick-tip.
The structure is the same as that used conventionally and is simple, and the number of parts is reduced, leading to cost reductions. Also,
Unlike the magnetic field modulation method, it uses a laser modulation method, so it has the advantage of being able to increase the recording frequency and easily record at a high transfer rate.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of the magneto-optical recording method of the present invention, FIG. 2 is a schematic diagram of the format of the present invention, FIG. 3 is a flowchart during recording and reproduction of the present invention, and FIG. 4 is a diagram of the conventional method. 1 is a schematic diagram of a magneto-optical recording method. 11...Data cell 12...Magnetization deafness 13...
・Recording waveform 14...Magnetization state 15...Reproducing waveform 16...Erasing waveform 21...Data cell
22... Magnetization state 23... Recording waveform 24...
・Magnetization state 25...Reproduction waveform 26...Recording waveform 27...Magnetization state m 28...Reproduction waveform 31
... Preformat section 32 ... Gap section 33 ... User area 34 ... Buffer part 35 ... Data management area 40 ... Sector information reading 41 ... Address discrimination 42 ... Polarity Setting 43...
・Clock delay 44...external magnetic field polarity switching 42...recording/playback 46...sector information rewriting and above Applicant: Seiko Epson Corporation 32 products Figure 3-----------R section 40

Claims (2)

[Claims] (1) In a recording method of a magneto-optical recording and reproducing device that records and reproduces information on a magneto-optical recording medium by narrowing a laser beam to a minute diameter, information is recorded in a data management area on the magneto-optical recording medium. The information recording method of the sector is determined by reading the sector information in the sector, and the data is erased by switching the externally applied magnetic field and turning on/off the delay of the recording data pulse in accordance with the information in the data management area. A recording method for a magneto-optical recording/reproducing device, which is characterized in that overwriting can be performed without requiring any operation. (2) A patent claim characterized in that, when the period of one data cell is T, the width of the recording data pulse is equal to or less than T/2, and the delay time between the recording data pulses is T/2. A recording method for the magneto-optical recording/reproducing device according to item 1.