JPS6257166A - Disk discriminating device - Google Patents

Abstract

PURPOSE:To discriminate whether a disk is a concentric circle shape or a spiral shape by inputting a track number data on the disk in one rotation timing of the disk, and comparing the data before and after one ration. CONSTITUTION:An output terminal of a latching circuit 24 is connected to the other input terminal of a comparator circuit 23 through a delaying circuit 26, and in the circuit 23, a track number data outputted from the circuit 24 is compared with a data which is outputted from a demodulating circuit 22 after one rotation of this latched data and applied to one input terminal. In accordance with whether the data which are applied to both these input terminals are equal or not, whether the disk which is used is a concentric circle- shaped disk or a spiral-shaped disk can be discriminated. In this regard, this discrimination is executed in a state that it is not kept in a track number, therefore, in case of the concentric circle-shaped disk, the same track is scanned, and in case of the spiral-shaped disk, the spiral is scanned.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field 1] The present invention relates to a disc discriminating device that is capable of discriminating whether tracks of a used disc are spiral or concentric.

[Prior art] In recent years, information has become increasingly popular. The development of related industries is remarkable, and the amount of information handled is rapidly increasing.

Therefore, instead of using conventional magnetic heads to record and read information, optical heads or optical pickups that use light are used to record at high density and play back at high speeds. Optical information recording and reproducing devices that can perform the following are attracting attention.

By the way, many optical recording media are in the shape of a disk called a disk, and the tracking servo state is such that a light beam is irradiated onto a track formed by concentric or spiral guide grooves (groups). The recording or playback is performed while the data is held in the same state.

The above-mentioned disks in which the groups are concentric or spiral-shaped can in principle be used to record on or play back on one disk without requiring any major changes, using a disk recording/playback device that can record on or play back on the other disk. Can be recorded or played back. [Problems to be Solved by the Invention] However, since the conventional device could record or reproduce only one of the disks in the concentric circle group or the disk in the spiral group, there was a problem in that a device was required for each disk. there were.

Therefore, a device that identifies whether the recording is concentric or spiral, and performs recording or reproduction using the same device based on the identification, would be a very effective device.

The present invention has been made in view of the above points, and is relatively P! ilB! It is an object of the present invention to provide a disc discriminating device which can distinguish whether a group of discs is a concentric circle or a spiral disc.

[Means for Solving Problems and Effects 1] The present invention has a means for capturing track number data on a disk at the timing of one rotation of the disk without track keeping, and whether the data matches before and after one rotation. Comparing means for comparing whether the disk is concentric or not is provided so that it can be determined whether the disk is concentric or spiral.

[Example] Hereinafter, the present invention will be specifically described with reference to the drawings.

Figures 1 to 3 relate to the first embodiment of the present invention.
The figure shows the configuration of the main parts of the disc discrimination circuit of the first embodiment, FIG. 2 shows the configuration of an optical recording information reproducing apparatus equipped with the first embodiment, and FIG. 3 shows the disc used. .

As shown in FIG. 2, the (optical recorded information) reproducing device @ 1 equipped with the disc discrimination circuit of the first embodiment records the disc 4 as a disc-shaped recording medium using the objective lens 3 forming the optical pickup 2-. This makes it possible to irradiate a beam of light.

The (optical) pickup 2 is housed in a housing (not shown), and this housing is attached to a movable carriage so that the pickup 2 can move in the radial direction R of the disk 4 together with the carriage. still,
The carriage is driven by a motor, for example via an alpha belt.

The pickup 2 converts light emitted by a laser diode 5 into a parallel beam using a collimator lens 6, passes, for example, P-polarized light through a polarizing beam splitter 7, converts it into circularly polarized light using a quarter-wave plate 8, and totally reflects it using a prism 9. to change the direction of travel,
The recording surface of the disk 4 can be irradiated with the light that has been condensed through the objective lens 3.

The light reflected on the recording surface of the disk 4 is transmitted through the objective lens 3.
is focused into a parallel beam of light, reflected by prism 9, and 1/4
The light is made S-polarized by the wave plate 8, enters the polarizing beam splitter 7, and is reflected in the right angle direction.

The light reflected by the polarizing beam splitter 7 is reflected or transmitted by the substantially critical angle surface of the critical angle prism 11, and the reflected light is collected by the condenser lens 12 and received by the 4-split light detector 13. .

The four-division optical detector 13 consists of four-divided light-receiving elements Pa, Pb, r'c, and Pd.
, Pb by the adder A1 and the added output by the adder A2 of the opposing light receiving elements Pc and Pc+ are outputted as a focus error signal SF through a differential amplifier (or subtracter) Dl.

Calculation of the light receiving elements Pa and Pc by the adder A3
The addition output by 4 to the adder of the light receiving elements Pb and Pd facing each other is outputted as a tracking error signal S through a differential amplifier D2.

Further, all the light receiving elements Pa and Pb are passed through the adder A5.

The added signal of Pc and Pd is output as a reproduced data signal and input to a demodulation circuit, and recording information data is recorded at the output of this demodulation circuit.

The focus error signal SF is used to move the objective lens 3 slightly in the direction F perpendicular to the disk surface to maintain the focused state when performing recording or reproduction by irradiating the disc 4 with a light beam. It is applied to a focus coil (not shown) movable in direction F.

Further, the tracking error signal ST is transmitted to the objective lens 3.
is applied to a tracking coil (not shown) that allows the disc 4 to move in the radial direction R, thereby being used to maintain the target track.

In addition, an optical detector 1 for detecting one revolution is placed opposite the disk 4 at a position different from the movable optical pickup 2.
A light reflecting part or a non-reflecting part is provided at one place on the circumference of the disc 4 facing the optical detector 19, and one revolution is detected in a step manner every time the disc 4 makes one revolution. This is so that the signal Sr can be obtained.

It is possible to detect whether the disk 4 is being rotated at a predetermined number of rotations based on the cycle at which this one rotation detection signal Sr is detected.

By the way, as shown in FIG. 3, the disk 4 used in the reproducing apparatus 1 according to the first embodiment has concentric groups Gi arranged along each recording type track on the recording surface of the disk 4.
There is a disk 4A formed with (mm・-1, 2, . . . ), and a disk 4B formed with spiral-shaped groups G', and each group G', G'
Information is recorded in bits at the bottom center of h.

Each track has an ID section in which each group Gi, G-t records an ID such as its track number or sector number if each track is further divided into a plurality of sectors, as shown in FIG. and an adjacent data section adjacent to the ID section, the ID section is formed in advance, and data can be written into the data section later with the light intensity m increased. Group part Gi, G'
At that time, the tracking servo is for guiding and holding the light beam on a predetermined track, and this tracking servo is performed based on the focus error signal SF. In addition, in the spiral disk 4B, 11
For convenience, the track numbers are set to be different every time the disk 4B is rotated 360 degrees. Therefore, the target track can be randomly accessed similarly to the concentric disk 4A.

By the way, when accessing a target track and reproducing or writing data in the data section to the target track, in the concentric disk 4A, if the track number of the target track is read out, if the track number of the target track is read out, the tracking servo state is maintained. , data can be read from the data portion of any sector in that track.

On the other hand, in the case of the spiral disk 4B, even when the target track number is read out, there are cases where the target track number has passed the sector number to be reproduced. Although there may be cases where it is not possible to read the data in the discriminator circuit 2, in one embodiment of the present invention, the discriminator circuit 2 as shown in FIG.
This can be done by providing 1.

That is, the reproduced data signal is binarized by a demodulation circuit 22 using a comparator or the like, and the track number of the ID part is extracted from the binarized reproduced signal, and one digital data of the track number is extracted. is serially input to a shift register in the demodulation circuit 22 with the number of bits corresponding to the data, and when the data with the number of bits is stored from the parallel output terminal 22a, for example, the clock pulse period of the number of bits is , parallel output end 22a
The digital data is applied to the digital comparator circuit 23 and also applied to the data input end of the latch circuit 24.

By the way, the one-rotation detection signal Sr is activated by the one-shot multi-vibrator circuit (
25 (hereinafter referred to as mono multi-circuit) is activated to output a short pulse, and the output of the inverted output terminal of this mono multi-circuit 25 is applied to the clock input terminal GK of the latch circuit 24, and is applied to the clock input terminal CK. Digital data applied to the data input terminal at the rising edge of a pulse is latched, and the data is output while the applied pulse is at a high level. In addition, the above inverted output &i? ) rises to a high level is set at the time when the MA circuit 22 outputs the track number discrepancy data.

The output terminal of the latch circuit 24 is connected to the other input terminal of the comparator circuit 23 via a delay circuit 26 for timing adjustment, and the track number data output from the latch circuit 24 and this The latched data is compared with the data output from the demodulation circuit 22 after one revolution.

The comparison output by the comparator circuit 23 is performed during the period when data is applied to the other side of the comparator circuit 23 via the delay circuit 26, and it is determined whether the data applied to the re-input terminal is equal or not. It is possible to distinguish between the concentric disk 4A or the spiral disk 4B. In addition, when performing the above discrimination, it is naturally performed in a state where the track number is not kept, that is, a light beam is irradiated along the group. Therefore, on a concentric disk, the same track is scanned, and on a spiral disk, the same track is scanned. will be scanned.

Based on the determined output of the comparator circuit 23, reading or writing is performed depending on the concentric disk 4A or the spiral disk 4B.

For example, if the concentric disk 4A is detected,
When reading data in a certain sector of a target track, if that track is accessed, the desired sector in that track will be irradiated with a light beam while the disk rotates once after access. You can read the data in that sector.

On the other hand, when it is determined that the disk is a spiral disk 4B, when reading data in a sector with a target track in the same way as above, when accessing the pick-up target track scent, if the sector is at an angular position that can be accessed continuously, The above concentric disk 4A? Data reading can be performed similarly. When the sector is at an inaccessible angular position (that is, the light beam has already passed), the track jump is performed at the timing position where the track number changes and the sector is returned to the first angular position of the target track number. Data within the sector at the position of that track number can be read.

In other words, in the case of the spiral disk 4B, when reading data on a target track, until the data on that track number is read, the track jump is performed by scanning back by one track at the angular position where the track number changes. A keep is performed. Therefore, when accessing a target track and reading data from the spiral disk 4B, a circuit is activated to read the track number and output a track jump pulse at the timing when the track number q changes. In addition, if it takes time to jump a track, you can take the time required to return to the target sector, or determine whether the read sector number has passed the target sector and check if it has passed the target sector. In this case, the track number will be held until the track number changes, and a track jump may be performed.

Conversely, when data is recorded over several tracks and these data are to be read, if these data are recorded along a spiral track, the data for one track can be read like the concentric disk 4A. The attack was a trunk attack on the adjacent truck! without causing any
Data can be read continuously. In other words, when reading sequential data for several adjacent tracks, jump pulses may not be necessary for the spiral disk 4B.

FIG. 5 shows a discrimination circuit 31 according to a second embodiment of the present invention.

The reproduced data signal is input to the demodulation circuit 32, where it is binarized, the ID portion is extracted, and the signal is sequentially output from the output terminal. This output is applied to the data input terminal of the shift register 34 and one input terminal of the comparator 35. Further, signal pulses from the trailing edge of each data section or the leading edge of the next ID section in the demodulation circuit 32 are transmitted to the output terminal 32.
b, and this pulse is applied to the monomulti circuit 37 via the AND circuit 36.

Moreover, the one rotation detection signal Sr is generated by the two-man powered AND circuit 3.
6 and output from the output terminal 32b when this signal Sr is at high level, the next ID
A one-shot pulse that remains at a high level until the end of the data period is output, and this pulse is applied to the reset terminal of the mono multi-circuit 38 activated by the one-rotation detection signal Sr. Set the output pulse to low level.

The monomulti circuit 38 outputs a one-shot pulse at the rising edge of the one-rotation detection signal Sr, and this pulse
The clock input EC of the shift register 34 is applied to the manually operated AND circuit 39, and is outputted from the output terminal 32G of the demodulation circuit 32 during the period when this pulse is at a high level.
This is so that the data input from the data input end can be serially captured. Since the mono multi circuit 38 is reset by the output of the mono multi circuit 37, only the first ID data when the one rotation detection signal Sr is output is taken into the shift register 34 by the number of γ-ta bits. That's how it is.

The ID data outputted from the output end of the shift register 34 one revolution before is applied as serial data to the other input end of the comparator circuit 35, and compared bit by bit with the data outputted from the demodulation circuit 32. If the number of bits corresponds to the data, it is identified as a concentric disc, while if it is uneven, it can be identified as a spiral disc.

Incidentally, the disc can also be determined based on whether or not only the last pit matches.

In addition, various types of discrimination circuits can be configured.

It is clear that the present invention can also be applied to optical pickups having different structures.

Furthermore, the present invention can be widely applied to devices that perform at least one of reproduction, recording, and erasing.

Furthermore, the present invention is not limited to devices that optically perform recording, reproduction, and erasing, but can also be applied to devices using a capacitance method or other methods. .

[Effects of the Invention] As described above, according to the present invention, since a means for determining whether the disk is concentric or spiral is provided, the operation of the disk is controlled in accordance with the signal from the determining means. It can be switched to match the disc.

[Brief explanation of the drawing]

Figures 1 to 3 relate to the first embodiment of the present invention.
FIG. 2 is a block diagram showing the discrimination circuit of the first embodiment; FIG. 2 is a perspective view showing the main parts of a playback device equipped with the discrimination circuit;
FIG. 3 is an explanatory diagram showing a concentric disk and a spiral disc discriminated in the first embodiment, FIG. 4 is an explanatory diagram showing the configuration of each track, and FIG. 5 is a diagram showing the discrimination in the second embodiment of the present invention. It is a block diagram showing the circuit. DESCRIPTION OF SYMBOLS 1... Recorded information reproducing device, 2... Optical pickup, 3 Objective lens, 4... Disk, 5... Laser diode, 13... Optical detector, 21... Discrimination circuit, 22... Demodulation circuit, 23... Comparator circuit, 24... Latch circuit, 25... One-shot multivibrator circuit, 26... Delay circuit Figure 1 @ Figure 2

Claims (1)

[Claims] A means for reading track number data formed on a track without track keeping in a disc device capable of recording, reproducing, or erasing information on a disc using a pickup. , a detecting means for detecting whether or not the track number matches the track number data read after one revolution.