JPH02208876A - Recording and/or reproducing device for card-like recording medium - Google Patents

Abstract

PURPOSE:To always efficiently perform the recording/reproducing by positioning a recording/reproducing head to an expected scanning completion position based on a stop position signal and an output of a position detecting means when an off-track is detected. CONSTITUTION:When the off-track takes place, the occurrence of the off-track is detected in a control circuit 12 by fluctuation of a tracking signal, and by its control signal, a changeover circuit 8 is changed an output to a driving circuit 13 to an output of a difference signal output circuit 7 from an output of a deviation signal circuit 11. Consequently, a position control of an optical pickup 2 is changed from a 1st position control loop to a 2nd position control loop passing through a linear scale 4, the difference signal output circuit 7, the changeover circuit 8, the driving circuit 13, a linear motor 3 and the optical pickup 2, and the optical pickup 2 is drive-controlled via the driving circuit 13 and the linear motor 3 by a difference signal from the difference signal output circuit 7, so as to be positioned in an expected track position after completing the movement of a card. By this method, the read/write operation can effectively and swiftly be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a recording and/or reproducing device for a card-shaped recording medium.

[Conventional technology]

As a conventional recording and/or reproducing device for a card-shaped recording medium, for example, an optical card is used, and information is optically recorded or reproduced by moving the optical card and an optical pickup relatively back and forth in the track direction of the optical card. Various methods have been proposed to do so. Such optical card recording/
In the playback device, an ID section in which track addresses and the like are recorded is provided at both ends of the track of the optical card, and information is recorded/played in both directions of relative reciprocating movement in the track direction between the optical card and the optical pickup. It is efficient to do this, and if a track goes off track during recording/playback, it is preferable to record/play back from the opposite direction or to seek another track to record/play back. .

On the other hand, as a conventional information reading device,
No. 460 discloses, in a device using a disk-shaped recording medium, a first control loop for driving and controlling a reading element so that the reading light is positioned on a track based on a tracking error signal, and a first control loop for driving and controlling a reading element in the disk radial direction based on a tracking error signal. and a second control loop that drives and controls the reading element based on the position signal of the first control loop.Normally, the first control loop drives the reading element to read information, and when off-track is detected, A method has been proposed in which the first control loop is switched to the second control loop to position the reading element at the instant when track off occurs.

[Problem to be solved by the invention]

However, when the control device disclosed in Japanese Patent Publication No. 616460 is applied to a device using a card-shaped recording medium, the following problems arise.

In other words, in card-shaped recording media, there is generally a deviation (skew) between the relative reciprocating direction of the medium and optical pickup and the track direction of the medium, so when an off-track occurs, the optical pickup is moved off-track. If the position is positioned at the time of occurrence, the track will be deviated at the end point of the relative movement. Therefore, when recording/reproducing from the opposite direction, it is necessary to seek the same track again, which deteriorates the efficiency of recording/reproducing.

Furthermore, even when seeking another track, the track shifts at the end point of the relative movement direction, so the accuracy of positioning to the target track decreases, and as a result, the seek time takes longer.

The present invention was made in view of these problems, and provides a card that is appropriately configured so that information can be recorded/reproduced efficiently at all times, and a desired track can always be sought in a short time. An object of the present invention is to provide a recording and/or reproducing device for a type of recording medium.

[Means and operations for solving the problem] In order to achieve the above object, the present invention provides a card-shaped recording medium and a recording/reproducing head that are relatively moved back and forth to record and/or reproduce information. In a recording medium recording and/or reproducing apparatus, a driving means for driving the recording/reproducing head in a direction orthogonal to a direction of relative reciprocating movement with respect to the card-shaped recording medium; a position detecting means for detecting the position of the playback head; a means for detecting the skew amount of the tracks of the card-shaped recording medium with respect to the relative reciprocating direction; means for generating a stop position signal of an expected scanning end position of the recording/reproducing head in the track based on the output of the position detecting means; and means for detecting an out-of-track position of the recording/reproducing head; When the deviation is detected, the drive means moves the recording/reproducing head from the scan start position on the track by an amount of skew to an expected scan end position based on the stop position signal and the output of the position detection means. configured to position.

〔Example〕

FIG. 1 shows a first embodiment of the invention. In this embodiment, an optical card 1 is used as the card-shaped recording medium, and is caused to reciprocate substantially in the track direction of the optical card 1 by a drive device (not shown). optical card 1
An optical pickup 2 serving as a recording/reproducing head that irradiates a light beam for recording or reproducing is moved by a linear motor 3 in a direction perpendicular to the reciprocating direction of the optical card 1, and its moving position is set by a linear scale 4. The position signal is detected by the skew amount detection circuit 5 and the calculation circuit 6.
and the difference signal output circuit 7, respectively. The skew amount detection circuit 5 detects the skew amount at the scan start point and the scan end point of the track with respect to the reciprocating direction of the optical card 1 based on the position signal from the linear scale 4, and supplies this to the arithmetic circuit 6. Make it. Furthermore, the calculation circuit 6 calculates the expected stop position of the optical pickup 2 at the end of scanning in each track based on the position signal from the linear scale 4 at the scanning start point and the output of the skew amount detection circuit 5. , the stop position signal is supplied to the difference signal output circuit 7.

Further, the difference signal output circuit 7 detects the difference between the stop position signal from the arithmetic circuit 6 and the position signal indicating the current position from the linear scale 4, and supplies the difference signal to the switching circuit 8.

On the other hand 1. In the optical pickup 2, the output of a detector (not shown) that receives the reflected light from the optical card 1 is supplied to the tracking servo circuit 10, and the optical card 1 is irradiated with a light beam based on the tracking error signal detected here. The light beam is positioned on the track by slightly displacing an objective lens (not shown) in a direction substantially perpendicular to the track. This tracking error signal is
It is also supplied to the deviation signal circuit 11 and the control circuit 12, and the deviation signal circuit 11 detects the low frequency component of the tracking error signal and supplies it to the switching circuit 8.
The presence or absence of off-track is detected based on, for example, an amplitude change in the tracking error signal, and the output thereof is supplied to the switching circuit 8 as a control signal. switching circuit 8
Now, based on the control signal from the control circuit 12, when no off-track is detected, the output of the off-track signal circuit 11 is selected, and when off-track is detected, the output of the difference signal output circuit 7 is selected. The signal is sent to the drive circuit 13.
As a result, the optical pickup 2 is controlled to be driven in a direction perpendicular to the reciprocating direction of the optical card 1 via the linear motor 3.

The operation of this embodiment will be explained below with reference to the plan view of the optical card 1 shown in FIG.

Skew Amount Measuring Operation> This operation measures the amount of deviation between the reciprocating direction of the optical card 1 and the track, that is, the amount of skew, and is performed immediately after the optical card 1 is set in the apparatus. Below, they will be explained in order.

Immediately after the card is inserted, the optical pickup 2 is positioned at a specific position (home position) shown by black in FIG. In the skew amount measurement operation, first, the tracking servo circuit 10 is activated, and a light beam is positioned on the track of the optical card 1. The tracking error signal from the tracking servo circuit 10 is supplied to the switching circuit 8 via the deviation signal circuit 11, and then supplied to the drive circuit 13 when the tracking error signal becomes stable. This drives the linear motor 3 and picks up the optical pickup 2.
And position control of the linear scale 4 is performed. That is, the position control of the optical pickup 2 at this time is performed by a first position control loop that passes through the deviation signal circuit 11, the switching circuit 8, the drive circuit 13, the linear motor 3, and the optical pickup 2 based on the tracking error signal. . When this first position control loop becomes stable, the skew amount detection circuit 5 stores the position signal from the linear scale 4 as a scanning start position value (indicated by symbol a in FIG. 2).

Next, the optical card 1 is moved by a predetermined amount. This light card 1
With the movement of the optical pickup 2, the optical pickup 2 also changes the position of the track being irradiated with the light beam (indicated by reference numeral 1a in FIG. ) to the scanning end position indicated by ■, and when it reaches the scanning end position ■, the value of the position signal from the linear scale 4 at that time (the symbol is already shown in Fig. 2).
is taken into the skew amount detection circuit 5, and the difference between that value and the value a before movement is stored as the skew amount (c=ba).

<Operation during read/write> In the read/write operation, the optical pickup 2 is positioned by the first position control loop explained in the above-mentioned skew amount measurement operation.

Hereinafter, the position indicated by ■ in FIG. 2 will be explained as the scanning start position of the read/write operation.

At the start of the read/write operation, the arithmetic circuit 6 calculates the value of the position signal from the linear scale 4 (second
In addition, the skew amount C from the skew amount detection circuit 5 is added to or subtracted from the value d of the scan start position (indicated by the symbol d in the figure) depending on the moving direction of the optical card l, that is, forward or backward movement. The expected scanning end position on the track 1b is indicated by a stop position signal (symbol e in Fig. 2).
) is supplied to the difference signal output circuit 7. The difference signal output circuit 7 receives the stop position signal (e=d+
'c) and the position signal indicating the current position of the optical pickup 2 from the linear scale 4, and outputs the difference signal to the switching circuit 8. However, in a state where no off-track occurs, the switching circuit 8 outputs an off-track signal. Since the output of the circuit 11 is selected, this difference signal is not supplied to the drive circuit 13, and the optical pickup 2 is positioned by the first position control loop described above.

<Operation when track-off occurs> During read/write operations, when the light beam scans the defective part 1c such as dust or scratches on the track lb as shown in Fig. 2, the tracking error signal is disturbed and track-off occurs. do. At this time, the control circuit 12 detects that a track deviation has occurred from fluctuations in the tracking signal, and in response to the control signal, the switching circuit 8 changes the output to the drive circuit 13 from the output of the deviation signal circuit 11 to the difference signal output circuit 7.
Switch to output. As a result, the position control of the optical pickup 2 is performed from the first position control loop to the linear scale 4, the difference signal output circuit 7, the switching circuit 8, and the drive circuit 13.
, the optical pickup 2 is driven and controlled by the difference signal from the difference signal output circuit 7 via the drive circuit 13 and the linear motor 3, and the card is moved. It is positioned at the expected track position after completion (the expected scan end position of the track 1b).

As described above, according to this embodiment, when an off-track is detected, the optical pickup 2 is positioned at the expected scanning end position of the track, so when the optical card 1 is moved in the reverse direction, the optical pickup 2 is 2 will be located on the same track, so reading from the opposite direction/
It becomes possible to perform write operations efficiently and quickly.

Also, when seeking to other tracks, you can perform the seek operation based on the expected scan end position.
It becomes possible to seek the target track quickly and accurately.

FIG. 3 shows a second embodiment of the invention. In this embodiment, the linear scale 4 in the first embodiment is omitted, and the output of the detector of the optical pickup 2 is supplied to the skew amount detection circuit 5, where the optical card is moved while the optical pickup 2 is fixed. The amount of skew is detected from the change in the nearest track to the optical pickup 2 before and after the movement, and is supplied to the arithmetic circuit 6. Further, the drive current of the linear motor 3 output from the drive circuit 13 is supplied to the observer circuit 15, where a predetermined calculation is performed to detect the position of the optical pickup 2 in the direction orthogonal to the reciprocating direction of the optical card 1. Then, the observer position signal is supplied to the arithmetic circuit 6 and the difference signal output circuit 7, respectively.

The other configurations are the same as in the first embodiment.

The operation of this embodiment will be explained below with reference to the plan view of the optical card 1 shown in FIG.

<Skew Amount Measuring Operation> This operation is performed with the optical pickup 2 fixed at a specific position (for example, home position) after the card is inserted.

As a method for fixing the optical pickup 2 at the home position, any fixing force method is used, such as a mechanical fixing method using a stopper, a positioning member, etc., or an electrical fixing method using a signal from a sensor or the like.

As shown in FIG. 4, when the optical card 1 is moved with the optical pickup 2 fixed at the home position (2), the optical pickup 2 will be at the O of the optical card 1 at the end of the movement position.
Located in the position of Here, the nearest truck before movement is A, and the nearest truck after movement is B. Since the tracks of the optical card 1 are parallel and equally spaced, the amount of skew can be determined from the difference between the track addresses of tracks A and B.

Specifically, in the optical card 1 shown in FIG. 4, each track has an ID section (I
DI and ID2> are formed, so when the optical pickup 2 is at the home position ■, the tracking servo circuit 10 is activated to irradiate the optical beam onto the track A, and the output from the optical pickup 2 in the section of IDI is activated. is demodulated by the skew amount detection circuit 5 and the address of track A is stored. Thereafter, when the IDI section is passed, the operation of the tracking servo circuit 10 is stopped, and it waits until the ID2 section comes to the position of the optical pickup 2. When the ID2 section reaches the position of the optical pickup 2 (I shown as 0 in Fig. 4)
At the beginning of section D2), the tracking servo circuit 10
The operation is restarted to irradiate the track B with a light beam, and the output of the optical pickup 2 at that time is similarly demodulated by the skew amount detection circuit 5 and the address of the track B is stored.

The skew amount is determined from both the addresses of tracks A and B thus determined and stored.

In addition, in order to obtain an accurate skew amount including the skew amount within the ID2 section, after moving the optical card 1 to the movement end position ■, operate the tracking servo circuit 10 and move the optical card 1 in the reverse direction. It is also possible to read the track address of the section ID2 by moving the track address to the track address of the section ID2, and detect the skew amount from this track address and the track address of the section IDI.

<Operation during read/write> During operation during read/write, optical pickup 2
As in the first embodiment, the first control loop passes through the deviation signal circuit 11, the switching circuit 8, the drive circuit 13, the linear motor 3, and the optical pickup 2 based on the tracking error signal from the tracking servo circuit 10. Positioned. In this read/write operation, the observer circuit 15 detects a change in the position of the optical pickup 2 by integrating the drive current supplied from the drive circuit 13 to the near motor 3, for example twice, and outputs the output (observer circuit 15). position signal) is supplied to the arithmetic circuit 6 and the difference signal output circuit 7, respectively.

In the calculation circuit 6, based on the observer position signal immediately before the start of card movement (for example, the scan start position ■ of the track 1b) and the skew amount from the skew amount detection circuit 5, the stop position of the expected scan end position ■ of the track 1b is determined. A signal is created and supplied to the difference signal output circuit 7. Further, the difference signal output circuit 7 detects the difference between the stop position signal from the arithmetic circuit 6 and the observer position signal indicating the current position of the optical pickup 2 from the observer circuit 15, and outputs the difference signal to the switching circuit 8. However, in a state where no track deviation occurs, the switching circuit 8 selects the output of the deviation signal circuit 11, so this difference signal is not supplied to the drive circuit 13, and the optical pickup 2 is controlled by the first position control loop described above. Positioned.

(Operation when track deviation occurs) During read/write operations, when the light beam scans the defective IC such as dust or scratches on track Ib as shown in Figure 4, the tracking error signal is disturbed and trunk deviation occurs. do. At this time, as in the first embodiment, the control circuit 12 detects that a track off has occurred from the fluctuation of the tracking signal, and the switching circuit 8 changes the output to the drive circuit 13 to the deviation signal circuit according to the control signal. 1
1 to the output of the difference signal output circuit 7. As a result, the position control of the optical pickup 2 is switched from the first position control loop to the second position control loop that passes through the difference signal output circuit 7, the switching circuit 8, and the drive circuit 13, and the optical pickup 2 is switched from the first position control loop to the second position control loop that passes through the difference signal output circuit 7, the switching circuit 8, and the drive circuit 13. The driving circuit 13 and the linear motor 3 are controlled by the difference signal from the circuit 7, and the card is positioned at the expected track position (2) (the expected scanning end position of the track 1b) after the end of card movement 7.

Therefore, as in the first embodiment, when the optical card 1 is moved in the opposite direction, the optical pickup 2 is located on the same track, so that read/write operations from the opposite direction can be carried out efficiently (and quickly). In addition, when seeking other tracks, it is possible to perform the seek operation based on the expected scan end position, making it possible to seek the target track accurately and quickly. .

Note that the present invention is not limited only to the embodiments described above, and numerous modifications and changes are possible. For example, the amount of skew can also be determined by proportional calculation based on the card drive position at the time when the off-track occurs and the position signal of the optical pickup 1 at that position. Further, in the above-described embodiment, the optical card 1 is moved back and forth substantially in the track direction, but the optical pickup 2
Alternatively, both may be moved in the above direction. Furthermore, the present invention is not limited to optical cards, but can also be effectively applied to magnetic cards and other card-like recording media.

〔Effect of the invention〕

As described above, according to the present invention, when a track off is detected, the recording/reproducing head is positioned at the expected scanning end position of the track, so that the recording/writing operation can be performed from the opposite direction. It becomes possible to perform the seek operation efficiently and quickly, and it also becomes possible to perform the seek operation for other tracks accurately and quickly.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing a first embodiment of this invention, Fig. 2 is a diagram for explaining its operation, Fig. 3 is a block diagram showing a second embodiment of this invention, and Fig. 4 is a diagram showing its operation. FIG. 3 is a diagram for explaining the operation. l... Optical card 2... Optical pickup 3
...Linear motor 4...Linear scale 5.
... Skew amount detection circuit 6 ... Arithmetic circuit 7 ... Difference signal output circuit 8
...Switching circuit 10...Tracking servo circuit 11...Difference signal circuit 12...Control circuit 13
...Drive circuit 15...Observer circuit Fig. 1

Claims (1)

[Scope of Claims] 1. A recording and/or reproducing device for a card-shaped recording medium that records and/or reproduces information by relatively reciprocating a card-shaped recording medium and a recording/reproducing head, comprising the steps of: / a driving means for driving the reproducing head in a direction perpendicular to the direction of relative reciprocating movement with the card-shaped recording medium; a position detecting means for detecting the position of the recording/reproducing head in the driving direction by the driving means; means for detecting the skew amount of the track of the card-shaped recording medium with respect to the direction of relative reciprocating movement; means for generating a stop position signal of an expected scanning end position of the recording/playback head; and means for detecting off-track of the recording/playback head; The card-shaped recording is characterized in that the recording/reproducing head is positioned by the driving means at an expected scanning end position that is moved by a skew amount from the scanning start position on the track based on the output of the position detecting means. Media recording and/or playback device.