JPH06282860A - Optical recording device - Google Patents

Abstract

PURPOSE:To enable the pitch spacing distance between recording tracks at a connection part to be constant on connection recording for recording a new data after an already recorded track. CONSTITUTION:When recording new recording tracks #0,... after already recorded tracks ...#3, #2, #2 formed on an optical tape 17, a means for detecting the position of a light spot when reproducing the already recorded tracks is provided and then the position signal for at least one track is recorded in a memory. Then, when scanning a new track #0 or thereafter for additional recording, the position signal is read from the memory and is output as a tracking control signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing apparatus used in the technical field of information recording, for example, and more particularly to an optical recording / reproducing apparatus suitable for an apparatus for recording and reproducing information on an optical tape. .

[0002]

2. Description of the Related Art Recently, a recording / reproducing apparatus using an optical tape as a recording medium has been developed. Such a recording / reproducing device can record a large amount of information with high density. FIG. 7 shows a recording / reproducing apparatus using an optical tape as a recording medium, which the applicant previously applied (Japanese Patent Application No. 3-216819).
Is a laser emission source, 102
Denotes a beam splitter for separating the light beam, and the laser light emission source 100 incident on this beam splitter 102.
Light is emitted toward the galvanometer mirror 103.

Reference numeral 104 denotes an image rotator, and the image rotator 104 is the galvanometer mirror 103.
The deflection surface of the light reflected by is rotated, and the light deflection surface is rotated at 1/2 the number of rotations in synchronization with the rotating drum so that the light deflection surface is always in a constant direction on the tape. 105
Represents a focus actuator, and by moving an optical lens in the focus actuator 105 from the outside, it is controlled so that the light spot is focused on the tape.

Reference numeral 106 denotes a rotating mirror arranged in the center of the rotating drum 107, and the light reflected by the rotating mirror 106 passes through an objective lens 108 and a tape 109.
Is being irradiated. The surface of the tape 109 is a recording medium which is sensitive to light, and its traveling is controlled by a guide roller that scans obliquely along the peripheral side surface of the rotary drum 107 as described later. The tape 109
The contact angle between the rotating drum 107 and the rotary drum 107 is usually about 180 degrees, but the tape angle is not limited to 180 degrees, and another winding angle may be used. The inclination angle of the galvanometer mirror 103 is changed by an actuator controlled by a tracking error signal, and the light spot irradiated on the tape is tracked.

As already known, such a device modulates the light output from the laser light emitting source 100 with the recording data and irradiates it onto the tape 109, and the tape 109 running on the circumferential side of the rotary drum. Recording tracks are formed in the diagonal direction on the recording surface. In addition, by guiding the reflected light when the recording track is scanned to the photodetector 101 via the optical system, the tape 109
It is possible to read the data recorded on the disk and simultaneously obtain servo information for scanning the recording track by another detector (not shown).

[0006]

In order to record data at a high density in such an apparatus, (1) a guide groove to be a recording track is provided on the optical tape in advance, and based on this guide groove, Recording and playback are performed while tracking. (2) Recording is performed with a drum having high-precision shake characteristics by regulating the tape position by the guide lead provided on the peripheral side of the drum. Such a method can be considered.

However, the following problems occur in the above-mentioned recording method. In the above (1), the guide groove formed on the tape requires high accuracy, and it is difficult to suppress the manufacturing cost. In the above method (2), when additional recording is continuously performed on the recording track train of the data recorded by a certain device x by another device y,
Due to the difference in track bending determined by the guide lead having a processing error, there may be a case where the recording tracks are connected at equal pitches. An object of the present invention is to provide an optical recording / reproducing apparatus capable of solving all of the above problems.

[0008]

In order to solve the above-mentioned problems, the present invention is directed to a detecting means for detecting a tracking error of a recording / reproducing spot, a scanning means for performing tracking based on the detection result, and a signal processing for performing tracking servo. Means, detection means for detecting the spot position, signal processing means for outputting the track of the recorded track as a target position during additional recording, and control means for positioning the spot at the target position are provided.

[0009]

According to the above structure, the spot locus at the time of tracking is stored while tracking the recorded track row when additionally recording, and the locus is recorded as the target value when recording to the unrecorded portion. Since the spot position can be controlled, the connecting portions of the recording tracks can always have the same pitch.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 and 2 show the essential parts of an optical tape recording / reproducing apparatus to which the present invention is applied, FIG. 1 is an optical system thereof, and FIG. 2 is a schematic view showing a tape running system running around the rotary drum. .

In these figures, reference numeral 1 denotes a semiconductor laser, and the recording / reproducing light emitted from the semiconductor laser 1 is converted into parallel light by a collimator lens 2 and a galvano mirror through a beam splitter 3 and a quarter wave plate 4. The light is reflected at 7, and is incident on the objective lens 16 by the mirror 15 on the axis of the rotary drum 18. Then, a scanning recording / reproducing spot is formed on the optical tape 17 which is obliquely wound around the upper drum 18 and the fixed lower drum 20 and is supported for traveling. The reproduction detection light from the tape 17 returns through the same optical path, and the ¼ wavelength plate 4 and the beam splitter 3 converge the detection converging lens 6
And a signal detection system formed by the multi-divided detector 5.

By rotating the galvano mirror 7 in the direction of the arc arrow a for tracking, the spot on the tape 17 is displaced in the direction b of the arrow, and tracking control during reproduction can be performed. Set the rotation angle of the galvanometer mirror 7 to L
The ED 11A and the collimator lens 11A form parallel light, and the light is incident on the back surface of the galvano mirror which is being irradiated,
The reflected light is converged by a converging lens 8 into a one-dimensional position detecting element 1
The position signal of the spot on the tape 17 is obtained by detecting the position of the spot formed at 0.

This position signal is adjusted so as to be 0 when the optical axis is at the center of the lens, for example. (The position detecting element 10 is for converting the position of the light spot on the detector into an electric signal like S1543 manufactured by Hamamatsu Photonics.) The Dach prism 14 is held within the axis of the rotator motor 13 and the image rotation optical system is used. Forming system, drum motor 1
By synchronously rotating at 1/2 rotation speed of 9, the scanning direction of the galvano mirror is made to coincide with the tracking direction on the tape 17. The focus adjustment of the spot is performed by the actuator of the objective lens 16 not shown, but the focus actuator may be arranged immediately before or after the mirror 15.

Next, the tape running system will be described with reference to FIG. 2. The same parts as those in FIG. 1 are designated by the same reference numerals. In this figure, the optical tape 17 is pulled out from the supply reel 21 and guided by the guide 22 to the entrance guide 23. The inlet guide 23, together with the outlet guide 24, obliquely winds the 180-degree section tape 17 around a drum including an upper drum 18 and a lower drum 20. In the tape winding section, recording / reproduction is performed on the tape 17 by the laser spot formed by the objective lens 16 on the rotating upper drum 18.

The tape 17 is pressed onto a capstan shaft 25 of a capstan motor 26 by a pinch roller 27 and sent, and wound on a take-up reel 28. Thus, the information tracks recorded and reproduced on the optical tape 17 are
As shown in FIG. 3, recording tracks inclined in the oblique direction of the tape are formed.

Next, the operation of the optical recording / reproducing apparatus, which is a feature of the present invention, during joint shooting will be described. When recording new data on the same tape following the old recording tracks recorded on the tape and the same recording / reproducing apparatus is used, as shown in FIG. Thus, a recording / reproducing track is formed. Therefore, it is possible to avoid the deterioration of information even when the continuous recording is performed by the same device. However, for example, when data is successively recorded on a tape on which old data is recorded by the recording device X by a device Y different from the device X, as shown in FIG. 4, the connecting tracks have equal pitches. There are cases where it does not become

That is, tracks # 3 to # in FIG.
When the recorded track train by the device X indicated by 1 is run by the device Y, the track bends as shown in the figure due to the subtle difference in the tape paths. The recording spot locus by the device Y is a straight line # 0 'as shown by the alternate long and short dash line, and if a new track # 0' is recorded as it is after the existing track # 1, pitch irregularities are created between the tracks # 1 and # 0 '.

Therefore, in the present invention, when data is continuously recorded by another device, reproduction tracking is performed up to the already recorded recording track # 1, and the position signal of the galvano-mirror which moves the spot at the time of reproduction. Is recorded so that new data thereafter can be written based on this recorded data so that the spot loci after # 0 are at equal pitches to # 1, that is, the track loci shown by the dotted lines in the figure. Record.

Next, the joint spot position control will be described with reference to the signal diagrams of FIG. 5 and the block diagram of FIG. First, reproduction tracking is applied to the recorded track train by the device X. Playback tracking is performed as follows. FIG. 5 shows waveforms in the reproduction mode and the recording mode, and shows changes in the reproduction / recording RF signal 29, the tracking error signal 30, and the spot position detection signal 31.

Here, the tracking error signal is a signal corresponding to a case where the track pitch detected by the push-pull method is one cycle and the zero cross point is at the spot center of the track, and its amplitude is relative to the track and the spot. Indicates the position. The position reference signal 52 indicates a tracking error sample value when the reproduction beam enters the track and enters the tracking control state, as described later.

After the spot rushes into the tape winding section D shown in FIG. 2 at point B in FIG. 4, continuous tracking to follow the track is started. At this time, the tracking error signal from the track on the tape is sampled at, for example, point A, the galvanomirror is positioned so that it is constant, and the position detection signal 31 is stored.

Since there is no tape in the idle running section F shown in FIG. 2, the position detection signal 31 is used, and the galvanometer mirror is held at a fixed position so that this matches the position reference signal.
This position reference signal is determined at point B by a sampling tracking servo using a tracking error at point A so that the spot is located at the center of the track. The sampling tracking servo at the point A is performed by changing the tape feeding speed of the galvano mirror and the capstan motor 26.

FIG. 6 is a block diagram showing a main part of a tracking circuit to which the present invention is applied. In this figure, parts that are the same as those in FIG. 1 and FIG.

In the figure, 32 is a matrix circuit for generating a tracking error from the output signal obtained from the multi-divided detector 6, 33 is an analog multiplexer for switching the tracking control state of the light beam by a timing pulse as described later, and 34 is Phase compensation circuit, 35 is a drive circuit for driving the galvanometer mirror 7,
36 is a position detector 1 for detecting the position of the galvanometer mirror 7.
Position calculation circuit for calculating 0 signal, 37 is a subtractor, 3
8 and 40 are A / D converters, 39 and 41 are D / A converters,
Reference numeral 45 denotes a timing pulse generation circuit to which the drum PG signal 43, the drum FG signal 44 and the rotator RG signal 42 are input, and the output signal controls the analog multiplexer 33, the A / D converter and the like.

Reference numeral 46 denotes a digital signal processing circuit for performing control so that the output of each of the converters is taken into the waveform memory 47 and output from the waveform memory 47 at a predetermined timing particularly when the connection is performed. Also 48, 4
Reference numerals 9, 50 and 51 denote the capstan motor 2 with reference to the position reference signal output from the D / A converter 41.
6 is a subtractor, a phase compensation circuit, a motor drive circuit, and a speed detection circuit that form a servo circuit that controls the rotation of the motor 6.

Next, the operation of the above circuit will be described. In the dynamic tracking section D (B → C) of FIG. 5 (FIG. 2) during reproduction, the push-pull tracking error 3 obtained by the multi-division detector 5 and the matrix circuit 32.
0 is selected by the a contact of the analog multiplexer 33, the phase is compensated by the phase compensating circuit 34, and then input to the drive circuit 35 of the galvano mirror to form a closed loop to perform continuous tracking servo.

The position reference signal 52 is input to the digital signal processing circuit 46 after the tracking error sampling value at point A (entrance error sampling point) before the start of dynamic tracking is converted into digital data by the A / D converter 38. The time integration calculation is performed, and the DA converter 39 outputs from the point C (servo switching point) to the next point B (servo switching point). As a result, a closed loop for performing sampling tracking servo in which the spot follows the track center at point A is formed. In this closed loop, the gain crossover point is 1/10 of the sampling frequency so that the control characteristic becomes unstable due to the open loop phase rotation caused by sampling.
The loop characteristics are selected so as to be less than or equal to the degree.

In this way, reproduction tracking is performed up to # 1. When additionally recording to # 0, the position signal 31 of the dynamic tracking section obtained in the position holding section of # 1 is converted into digital data by the AD converter 40 and stored in the waveform memory 47. At this time, as the sampling pulse, an FG signal that matches the drum motor rotation angle of 19 or a signal obtained by synchronously multiplying the FG signal is used. During recording of the # 0 track, this data is read from the waveform memory 47 as waveform data corresponding to the drum rotation angle, and is output as the position reference signal 52 by the DA converter 39. After the holding section of # 0, the multiplexer 33 is switched to the lower contact b, and the locus of the recording spot is the position reference signal 52.
To follow. That is, it is recorded on the already-recorded track at equal pitches as shown by the dotted line in FIG.

At this time, the speed of the capstan is #
It is held at the speed of one playback. This process is a process for every one rotation of the drum as described in the specification “Japanese Patent Application Laid-Open No. 3-216819” filed earlier, but as described in this specification, the process of the drum due to the error of the rotator 104 is performed. If the loci of odd and even rotations are significantly different, the position signals of even and odd rotations # 2 and # 1 are stored, and then # 2 is changed to # 0.
# 1 may be used as # 1, # 2 may be used as # 2, and # 1 may be used as # 3.

The present invention is not limited to this embodiment, and includes, for example, an optical pickup incorporated in a rotary drum and a reference (P. Vogelgesang and J. Hartmann, "E.
rasable optical tape feasibility study, "SPIE, Opt
ical Storage Technology and Applications, vol.899,
pp. 172-177, 1988.) The recording method with a built-in reel in the drum is also possible.

Although the case of optical recording has been described, it can be applied to magnetic recording in which recording / reproduction is performed by the same method as in the above embodiment. Further, although the helical scan method has been described, for example, a method of winding the tape in the tape width direction on a drum, and recording / reproducing on a flat record carrier (sheet medium, card medium) not limited to the tape, for example, (Japanese Patent Laid-Open No. 59-59). It is also possible to apply it to the light beam scanning device described in JP-A-223949).

[0032]

As described above, according to the present invention, the following effects can be obtained. 1. As compared with the conventional case, the guide groove on the medium is unnecessary, and the manufacturing cost can be reduced. 2. Since the pitch unevenness does not occur in the jointed tracks when performing the additional recording, recording with a high track density can be performed without increasing the processing error between the devices.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of an optical system of an optical recording apparatus according to an embodiment to which the present invention is applied.

FIG. 2 is a schematic diagram showing a configuration of a traveling system of an optical tape to which the present invention is applied.

FIG. 3 is a track pattern diagram for explaining operations of a conventional example and one embodiment of the present invention.

FIG. 4 is a track pattern diagram for explaining the operation of the embodiment of the present invention.

FIG. 5 is a waveform diagram for explaining the operation of the embodiment of the present invention.

FIG. 6 is a block diagram showing an operation of the optical recording device according to the embodiment of the present invention.

FIG. 7 is a schematic diagram of an optical recording device showing a prior art of the present invention.

[Explanation of symbols]

 1 semiconductor laser 3 beam splitter 6 multi-divided detector 7 galvano mirror 10 position detection element 14 Dach prism 15 reflection mirror 16 objective lens 17 tape 18, 20 rotating drum 19 drum motor

Claims (3)

[Claims] 1. A laser emission source and a recording / reproduction that is applied to the recording medium in an optical recording apparatus that forms a discontinuous recording track by irradiating the recording medium with the output light output from the laser emission source. Detecting means for detecting a tracking error of the spot; scanning means for performing tracking based on the tracking error signal obtained from the light detecting means; position detecting means for detecting the absolute position of the spot being scanned; A signal processing unit capable of detecting the position of the recorded track by the position detection unit and outputting the locus thereof as the target position is used to position the spot at the target position by the signal output from the signal processing unit during additional recording. An optical recording apparatus having a control means. 2. The optical recording apparatus according to claim 1, wherein the position detecting means is configured to detect the position of the reflected light of the light irradiated behind the galvanometer mirror. 3. The recording medium is an optical tape wound around the circumference of a rotary drum.
Or the optical recording device according to 2.