JPS62264467A - Optical recorder - Google Patents

Abstract

PURPOSE:To prevent a track jump, a miserasing, and a misrecording, by providing a photosensor means which receives reflecting light, or transmitting light from a recording medium for an erasing beam, and obtaining a recording control signal from the photosensor means. CONSTITUTION:A control beam B3 is made incident on photosensors 12 and 15, and a focus error signal can be obtained from a four-sected photosensor 12, and a tracking error signal can be obtained from a bisected photosensor 15. And since an address signal can be obtained as the sum signal of the bisected photosensor 15, and the reflecting light of a recording beam B2 is not made incident on the photosensors 12 and 15, an accurate address signal can be obtained. According to the address signal, the direction of a current impressed on a coil 17 at every recording track is switched, then the polarity of a bias magnetic field is switched, and the recording of new information by the recording beam B2 can be performed, while erasing recorded information by an erasing beam B1. Thus, the miserasing, the misrecording, or the track, jump can be prevented from occurring.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to an optical recording device that is capable of writing new information while erasing information.

2. Description of the Related Art An information recording/reproducing apparatus using the magneto-optical effect is disclosed in, for example, Japanese Patent Laid-Open No. 117106/1983. According to this conventional technology, the information signal and the address signal are recorded on the same recording track (for example, the address signal is recorded in advance in a form that is aligned every revolution of the disk, that is, in one radial direction). (The configuration is such that erasing cannot be performed with the erasing beam), it is possible to erase previously recorded information with the preceding erasing beam and record new information with the subsequent recording beam. That is.

The erasing beam and the recording beam are irradiated to 9 tracks that are adjacent to each other or two or more tracks apart, and by detecting the address with the erasing beam and switching the polarity of the bias magnetic field for each track, the erasing beam can erase the existing recording. It becomes possible to record new information using a recording beam while erasing information.

C. Problems to be Solved by the Invention If there are scratches or the like on the recording medium, the address cannot be detected correctly during recording, resulting in track skipping. b, There is a habit of v4 erasure occurring.

2. Means for Solving Problems In the present invention, a photosensor means is provided for receiving the reflected light (or transmitted light) from the recording medium of the erasing beam that precedes the recording beam, and this photosensor means The configuration is such that a recording control signal can be obtained from the recording control signal.

The recording control signal is used to prevent track skipping by changing the gain or frequency characteristics of the focus servo system or tracking servo system, or to reduce the intensity of the erasing and recording beams.

Even if track skipping occurs, it is possible to prevent erroneous erasure and erroneous recording.

Embodiment In FIG. 1, the laser diode array (1) has three radiation points: an erasing beam (B1), a recording/reproducing beam (B2), and a control beam CB! I)
'Y Output. The beam passes through a collimator lens (2) and a beam splitter (3), and is focused onto the magneto-optical disk tD1 surface by an objective lens (4). As shown in the second factor, the erasing beam (B1) takes the lead, and the subsequent recording and reproducing beam (B2) records data adjacent to the recording track (T1) on which the erasing beam (B1) is focused. It is focused on track (T2) (it may be focused on a track that is two or more tracks away).

On the other hand, a control beam (B3) is focused on a control track (OT) of the disk [D], and an address signal [Al is recorded on a specific portion of this control track (for example, on one radial line of the disk). ing. control track (
The other part of the CtT) serves as a guide groove for tracking.

The recording track and the control track are formed in a spikele shape or a concentric circle shape with respect to the disk tDI.

The beam reflected by the disk tDI is transmitted through the objective lens (4) and the beam splitter! 31.3A wave plate (5),
The light passes through a condensing lens (6) and reaches a polarizing beam splitter (7).

It is separated into each polarization component (P component and 8 components) by a polarizing beam splitter (7), one is passed through an optical lens (81), and the other is directly sent to a photosensor means (9).
) reaches α1.

Photosensor means (91 (11) configuration Ifi as shown in the third factor. Respective photosensor means + 91 (10)
are three photosensors (131+12) (13, Q
41Q5) It has αe. Photo sensor 1111Q41
is at the position that receives the erasing beam (B1), 7-photo sensor Q31αG is at the position that receives the recording and reproducing beam (B2), and the photosensor (12) us is the control beam (CBS).
5: They are placed at receiving positions. Photo sensor a
2) is a 4-split 7f) sensor, and a photosensor (151 is a 2-split photosensor).

Now, during recording, the control beam (B3) is connected to the photo sensor f12)ti! As is well known in the art, a 7-occasion error signal can be obtained from the 4-split photosensor α2, and a re-tracking error signal can be obtained from the 2-split photosensor ttS. Then, the address signal can be obtained as the sum output of the two divided 7f) senna forceps (the sum output of the four divided photosensor 13 may also be used), and at this time, the reflected light of the recording beam (B2) is 7f to centimeter n.
Since it is not incident on cJaz, an accurate address signal can be obtained without being affected by the modulated recording beam. Based on this address signal,
By switching the polarity of the bias magnetic field by switching the direction of the current applied to the coil αη for each recording track.

It becomes possible to record new information using the recording beam (B2) while erasing existing edge information using the erasing beam (B1).

The feature of the present invention is that the erasing beam (B1) which precedes the recording beam (B2) is incident on the photo sensor (Il).
Disk ID from l (photo sensor [141 is also good)
The point is to obtain a control signal for detecting flaws tB1 etc. on I. If a flaw larger than a certain level is detected, this control signal is used to switch the laser power control circuit to 0, the focus control circuit to 0, and so on. The tracking control circuit is controlled to temporarily reduce the intensity of the erasing and recording beams. Alternatively, the loop gain and frequency characteristics of the tracking servo circuit and focus servo circuit are temporarily changed to prevent erroneous erasure, erroneous recording, and track skipping.

During reproduction, by reducing the intensity of the laser diode (11), a reproduction beam can be obtained from the laser diode (1) instead of the recording beam.

In this case, it is possible to obtain a reproduced signal from one of photosensor α3 and photosensor αG, but a configuration in which the difference output between these is obtained from an operational amplifier (OP) can obtain a reproduced signal lk with a better i9N ratio. can. Further, a focus error signal, a tracking error signal, an address signal, and a control signal can be obtained using the same configuration as when recording.

Although the embodiment described above is an example of magneto-optical recording, it is also applicable to a type of recording information by changing the reflectance or transmittance of the disk.

G. Effects of the Invention As stated above, according to the present invention, the condition of the disk surface is monitored using the erasing beam, and if there are scratches or the like, the intensity of the erasing and recording beams is temporarily reduced. let Alternatively, since the characteristics of the focus servo circuit or the tracking servo circuit can be temporarily changed, erroneous erasure, erroneous recording, and track skipping can be prevented.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an optical recording device according to the present invention. FIG. 2 is a diagram showing the relationship between the beam and the track, and FIG. 3 is a diagram showing the relationship between the beam and the photosensor. . (1) is a laser diode array, (3) is a beam splitter, (7) is a polarizing beam splitter, +91(1
G is a photosensor means, 111J is a photosensor means for erasing beam, CL81 is a laser power control circuit,
α value is the focus control circuit, c! G is a tracking control circuit.

Claims (3)

[Claims] (1) An optical recording device configured to erase with a preceding erasing beam and record with a subsequent recording beam, the photo sensor receiving reflected light or transmitted light from the recording medium of the erasing beam. An optical recording apparatus comprising means for obtaining a recording control signal from the photosensor means. (2) The optical recording apparatus according to claim 1, wherein the recording control signal is a signal for controlling the intensity of the erasing beam and/or the recording beam. (3) The optical recording apparatus according to claim 1, wherein the recording control signal is a signal for controlling characteristics of a focus servo circuit and/or a tracking servo circuit.