JPS62146440A - Optical recording and reproducing device - Google Patents

Abstract

PURPOSE:To decide accurately a recording/reproducing position by providing a means for reading out a format signal previously recorded on a disk in case of recording/reproducing a signal on the disk by a minute spot, a means for deciding the validity/invalidity of the reading, and a means for switching tracking control polarity. CONSTITUTION:A recording/reproducing device is constituted of a light source 10, a stop lens 40, an actuator 50, a spindle motor 200, a turn table 300, and an optional recording disk 400. A circuit for controlling the recording/ reproducing device is constituted of a tracking reproducing signal detecting photoelectric detector 60, a differential amplifier 70, an inversional amplifier 80, a switch circuit 90, a compensating circuit 100, a driving circuit 110, an addition amplifier 120, a shaping and demodulating circuit 130, and a reading deciding circuit 140. The device is constituted as mentioned above and format signals recorded in respective grooves or between respective grooves are read out and automatically decided, so that data can be recorded/reproduced in/from any optical disk.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention uses a light source such as a laser, narrows it down to a small diameter spot, and irradiates it onto an optical recording medium having an optical guiding function. The present invention relates to a recording and reproducing device that records and reproduces signals by penetrating optical guide means.

BACKGROUND ART Conventionally, as an example of an optical recording/reproducing apparatus, a method has been proposed in which a rotating optical recording disk is irradiated with a laser beam having a minute beam diameter. In this device, a signal is recorded by modulating the intensity of a laser beam irradiated onto an optical recording disk with the signal to be recorded, thereby using laser energy to record a predetermined signal onto an optical recording disk. It swamps in the guide groove and records at high density.

- To reproduce the optical signal, the recorded signal is reproduced by irradiating the signal recording area of the optical recording disk with laser light of a constant intensity and detecting changes in reflected light or transmitted light on the optical recording disk.

FIG. 1 is a configuration diagram of one embodiment of the present invention, and since the configuration is common to a conventional optical recording/reproducing device except for a part, FIG. I will explain about it.

In FIG. 1, 1o indicates a light source that generates light for recording and reproduction, and a laser diode or the like is used to generate a light beam l. Reference numeral 2o denotes a condensing lens, which condenses the output light of the expanding laser diode 1o into a substantially parallel original beam. 3o is a polarizing beam splitter, 40 is an aperture lens, and a minute light spot 402 is formed near the focal point of the aperture lens 4o. Reference numeral 60 schematically shows an actuator for driving the aperture lens 40 for conventional focus and tracking control. Reference numeral 60 denotes a photoelectric converter that detects reflected light from the optical recording disk 400 to detect a known tracking error signal and reproduction signal. The differential amplifier 70 outputs a tracking error signal, and the summing amplifier 120 outputs a reproduced signal. Reflected light from the disk, differential amplifier 70. Switch circuit 90. Servo compensation circuit 100. Drive circuit 110. The actuator 6Q constitutes a tracking control loop, 0200 indicates a spindle motor, and 30o indicates a turntable. 4
00 indicates an optical recording disk, 401 indicates a surface coated with optical recording material, and 402H indicates the minute light spot formed thereon.

Generally, optical recording disks are provided with optically detectable guide tracks in order to perform high-density recording in narrow trunks with simple recording and reproducing devices.

An optical slot 402 formed on the disk records and reproduces signals along this guide track or while having a certain relationship with the guide track.

Several methods have been proposed for forming optical guide tracks. For example, a spiral or concentric circle a of a specific depth is provided over the entire surface of the disk, and a signal is recorded in or between the grooves. A plurality of concave and convex pits are treated as a group, and this bit group is intermittently spirally Alternatively, methods have been proposed in which signals are recorded and reproduced along or between bit groups by arranging them concentrically on a disk and detecting a tracking error signal from this bit group. The optical guide track described above is inserted into an optical recording disk during a mastering process during disk substrate manufacturing, a formatting process during disk shipment, and the like.

FIG. 2 shows an enlarged example in which the grooves described above are used as optically detectable guide tracks. As shown in Figure 2, the shape of the groove is one with a rectangular cross section in the depth direction, one with a U-shaped cross section in the depth direction, and one with a V-shaped cross section in the depth direction.
One showing a glyph-shaped cross section has been proposed. However, from the point of view of the guiding function of the original spot, regardless of the groove shape, the principle is the same in that the tracking error signal is detected using the diffraction effect of the irradiated light.

FIG. 2 is an enlarged view showing a portion of the optical recording disk 400 in FIG. 1 near the optical recording material 401, and shows each groove (1, 3,
5...), the optical groove depth nd (n is the refractive index of the optical path base material, d is the groove depth) is approximately λ/8 (λ is the wavelength of the light source)
The groove width W is designed to have a value close to 0.4 to 1.
A value of about 0 μm is used.

Arrows indicate the radial direction of the disk, and arrow B indicates the tangential direction of the disk. As shown in the figure, the grooves are formed in the tangential direction of the disk, and are formed in the shape of spirals or concentric circles.

As shown in the figure, the laser beam for recording and reproducing passes through the disk base material and is irradiated in two directions along one groove and scanning the center of the groove or a position midway between the edges on both sides of the groove. . The fine light spot 402 is subjected to conventionally known focus control so that the beam waist is on the recording material 401.

In Fig. 2, when viewed from the incident light side, the concave part is called a groove, and the convex part is called a groove gap.
・) is the groove and s (2r' + 6...
...) part becomes the groove.

Next, when the original spot 402 in FIG. 2 moves across the groove relative to the groove in the direction of arrow R (radial direction of the disk), the differential amplifier 7Q detects the tracking error in FIG. As shown in FIG. 3, a signal indicating that the original spot 402 has crossed the groove is generated at the output terminal Y of. The integers 1, 2, 3...6 overflowing on the time axis t in Figure 3 are output when the light spot is at the center position of each groove or between grooves in Figure 2. shows the tracking error signal. That is, the odd-numbered points of b('+3+'') indicate that the original spot is at the center of the valley, the tracking error signal is zero, and the slope with respect to time at that time is positive.

On the other hand, even-numbered points (2, 4, 6) indicate that the original spot is located at the center between the grooves corresponding to each number, the tracking error signal is zero, and its slope with respect to time is negative.

In the conventional optical recording/reproducing device explained above, the second
Tracking control can only be applied to either the grooves shown in the figure or between the grooves. Therefore, signals can be recorded or reproduced only in the grooves of the disk or in a predetermined direction between the grooves. Furthermore, from the perspective of a blade-based recording disk, it is possible to achieve almost the same optical performance whether a signal is recorded or reproduced in the grooves or whether a signal is recorded or reproduced between the grooves. , there is no need to be limited to either one.

Problems to be Solved by the Invention As described above, there may be original discs that use the grooves or the space between the grooves as the information recording area of the original disc. (Also, when a guide track is formed using pre-pits, there may be a disk that records information over the pre-pits, or a disk that records information between the pre-pits.) The present invention is based on any of the above sources. It is an object of the present invention to provide an optical recording and reproducing device that can record and reproduce signals also on a disc.

Means for Solving the Problems The present invention provides a means for reading a format signal recorded in advance on a disk, a means for determining whether this reading is being performed accurately, and a means for switching the polarity of tracking control. This is an optical recording and reproducing device equipped with.

Operation The present invention uses the above-described configuration to read out format signals such as track address signals and sector address signals recorded in advance on a quintuple recording disk, and reads out format signals such as track address signals and sector address signals recorded in advance on a five-dimensional recording disk, and reads out format signals such as track address signals and sector address signals recorded in advance on a five-dimensional recording disk. ) By automatically switching the polarity of the tracking servo of the optical recording/reproducing apparatus, an apparatus capable of recording and reproducing signals on a defined surface corresponding to each disk can be obtained. In the block diagram of FIG. 1, 70 is the differential amplifier, which generates the tracking error signal shown in FIG. 3 at the terminal Y. In FIG.

80 is an inverting amplifier that inverts the polarity of the tracking error signal. Reference numeral 90 indicates a switch circuit, and terminals a and b are supplied with the tracking error signal and a tracking error signal with the polarity inverted. A signal from the common terminal C of the switch circuit passes through a servo system compensation circuit 100, passes through a drive circuit 110, and drives the tracking actuator 50.

On the other hand, the playback signal is output to the output terminal X of the summing amplifier 120, passes through the shaping and demodulation circuit 130, and is read by the ID reading determination circuit 140, which reads the format signal recorded in the grooves or between the grooves on the disk. , if the format signal cannot be reproduced and read accurately, the control circuit 150 is driven to send a control signal to the terminal d of the switch 90, for example, the switch is changed from (a-C) connection to (ba-a
) connection to change the tracking polarity 0 To explain the above switching using the original movement on the disk in Fig. 2, if the switch 90 in Fig. 1 is in the (!L-c) connection, the light in Fig. 2 Assuming that tracking control is performed on the groove of the disk, the polarity of the tracking error signal is reversed when the switch 9o is switched to the (bo) connection, and the optical slot 402 in FIG. teeth,
Tracking control is performed between the grooves, and the original spot scans between the grooves of the disk.

To explain the above again with reference to FIG. 3, the switch 90
In the case of (a-c) connection, (1, 3, 5,
The odd-numbered zero intersections (...) become the stable points for the servo, and the original spots run along the groove. On the other hand, when the switch 90 is in the (b-c) connection, (2, 4,
The even numbered zero crossing point (6...) becomes a stable point for the servo, and the original spot runs along the grooves of the disk.

FIG. 4 shows an enlarged example of a disk format section using grooves. FIG. 5 shows an enlarged example of a format section of a disk using groove sections.

Figure 4 shows a disc that records and reproduces signals in its grooves.

As shown in the figure, the format signal is inserted into the groove as shown in the figure.
(not shown) or the like, for example, in the form of a digital signal. Following this format signal, a signal is recorded along the groove by an optical recording/reproducing device. Show that one mark in ml.

Therefore, in the case of this disc, for example, the tracking control is applied to the groove 2, and the groove 2 is optically switched (402).
When scanning, the format signal reproduced at the first terminal X is a combination of the format signal of groove section 1 and the format signal of groove section 2 at a low level.
In this case, when the ID reading circuit 140 cannot make an accurate determination, the control circuit 150 can be driven to switch the switch 9o so that the original spot tracks the groove, and to read the format signal accurately. The figure shows a disc that records and reproduces signals in the grooves of the disc. Format signals are recorded in the grooves 2 and 4, and then signals are recorded by an optical recording and reproducing device (one Recording marks are indicated by m, .).

When this disc is used in the optical recording/reproducing apparatus shown in FIG.
By switching the terminal o, signals can be recorded and reproduced in a predetermined area of this disk (in the grooves or between the grooves, along the pre-pits, or overflowing between the pre-pits). Furthermore, when there are actually many format signals on one track on the disk, and only one of them is read by mistake, there is no need to change the polarity of the tracking control. It is considered that it is more practical for the ID reading determination circuit shown in FIG. 1 to include a majority circuit. Then, once the polarity of the carrier tracking is determined, the partial reading sheller
It is conceivable to configure the device so that the polarity is not reversed.

Effects of the Invention For example, it is possible to obtain an optical recording and reproducing apparatus that automatically determines whether a signal should be recorded and reproduced in the grooves of an optical recording disk or between the grooves, and that can handle any type of disk.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a perspective view showing an example of a grooved optical disk, FIG. 3 is a waveform diagram showing an example of a tracking error signal, and FIG. Enlarged view of the format part of the disc for recording and playing back, No. 5
The figure is an enlarged view of the format portion of a disc for recording and reproducing signals between grooves. 1o...Recording/reproduction light source, 40...Aperture lens, 6o...Actuator, 60...
···tracking. Photoelectric detector for playback signal detection, 2oO...Spindle motor, 300...Turntable, 4o
o...Optical recording disc. Figure 1: T-times, S νI Cape Circuit Figure 2: L Figure 3: Figure 4: Figure 5

Claims (1)

[Claims] A device that creates a minute light spot using light such as a laser and uses this minute light spot to record and reproduce signals on an optical disk. An optical recording/reproducing device comprising means for determining whether tracking control is being performed, and means for switching polarity of tracking control, and switching the polarity of tracking control when a format signal cannot be read accurately.