JPS628336A - Optical disc device - Google Patents

Abstract

PURPOSE:To eliminate the need for minute adjustment in the installation of an optical system and a carrying motor by shifting the generation of a reference signal in matching with the position of the optical system or shifting the timing signal based on the reference signal when the optical system moves to the inner or the outer circumference of a disc. CONSTITUTION:A delay quantity setting circuit 10 is adjusted so as to output an ideal waveform (b) when the reference signal 19 is inputted to the delay quantity setting circuit 10 at the outer circumference of the optical disc and the same waveform is outputted as a monitor signal 17. In this case, a signal with a delay time T1 is fed to an operation circuit 12 as a delay quantity signal 24. Similarly, the reference signal 19 moving the optical system toward the inner circumference is outputted as a monitor signal 18. A signal shown in figure (d) is identical to the ideal waveform (b) by adjusting a delay quantity setting circuit 11, and a delay quantity signal 25 having a delay time T2 is fed to the operation circuit 12. The operation circuit 12 converts the delay quantity signals 24, 25 into a voltage corresponding to them and the result is fed to a delay quantity deciding circuit 14 as operation signals 21, 22 (W, Z). Thus, generation of an accurate timing signal is attained.

Description

[Detailed description of the invention] Industrial applications The present invention has nine notched reflective markers on an optical disc.

The present invention relates to an optical disc device that generates a reference signal by detecting a sector mark, one rotation signal, etc. formed in advance using a reflective film, etc., and generates timing signals such as an address gate and a signal gate.

BACKGROUND OF THE INVENTION In FIG. 7, reference numeral 1 denotes an optical disk, 2 an optical system for recording and reproducing data signals, 3 a transport motor for moving the optical system 2 to the inner and outer peripheries, and 4 a photo sensor. Conventionally, this type of optical disc device uses a reflective photosensor 4, as shown in FIG. A method was adopted in which reference signals such as sector marks and one revolution signal of the disk were read by passing the amplifier 6° to the comparator 7. For example, an optical disk device similar to the optical disk device disclosed in Japanese Patent Application Laid-Open No. 57-103135 has been trusted. Conventionally, based on the signal detected in this way, an address gate signal (for example, JP-A-59-1481
No. 45), timing signals such as jumping signals and recording gate signals were generated.

Problems to be Solved by the Invention However, in this type of optical disc device, data signals,
Detection means for one rotation signal, sector mark signal, etc. were separate. Therefore, one revolution signal.

When a reference signal is generated by detecting a sector mark signal or the like, and a timing signal is generated using the reference signal, there is a problem that, for example, the address gate signal deviates between the inner and outer circumferences.

This will be explained using FIG. When the traveling direction of the transport motor 3 (the traveling direction of the optical system 2) intersects with the center of the optical disc 1 as shown in Figure 8 (b), the address gate is
), the address part was gated accurately. However, in Fig. 7(,), the transfer motors are 3a, 3b, 3.
In the case where the traveling direction does not intersect with the center of the optical disc 1, as shown in FIG. 8(C) (2a, 2b, 2c in the optical system).

The address gate shifts back and forth as shown in (d).

Even if the inner circumference is adjusted accurately, the outer circumference may be misaligned, and vice versa. If the transfer motor 3 and the optical system 2 are precisely installed, the address gate etc. will not shift. However, in reality, even if fine adjustment is performed, an error of several tens of micrometers will inevitably occur. As a result, as shown in FIGS. 8(C) and 8(d), misalignment of the address gates, etc. on the inner and outer peripheries becomes unavoidable. Furthermore, it takes a considerable amount of time to make fine adjustments in order to minimize the deviation, which is a bottleneck in mass production.

The present invention has been made in view of these points, and it reduces the time required to install the optical system and the transfer motor, and allows the optical system for reproducing data signals to be moved to any position on the inner or outer circumference of the disk.
It is an object of the present invention to provide an optical disc device that can generate accurate timing signals.

In order to solve the above-mentioned problems, the present invention provides an optical system for reading data signals recorded on an optical disc, and a reference signal by detecting sector marks, one rotation signal, etc. on the optical disc. The optical disc apparatus includes means for shifting the generation of the reference signal depending on the position of the optical system or for shifting a timing signal generated based on the reference signal.

(Function) According to the present invention, when the optical system moves to the inner and outer peripheries of the disk, the generation of the reference signal is shifted in accordance with the position of the optical system that generates the data signal, or the generation of the reference signal is shifted based on the reference signal. By shifting the timing signal by using the
Fine adjustments in the installation of the optical system and transfer motor (even with fine adjustments, deviations still occur) are unnecessary.

Embodiment FIG. 1 is a block diagram showing a first embodiment of the optical disc apparatus of the present invention. 10.11 is a delay amount setting circuit, 12
13 is an arithmetic circuit, 13 is a position signal conversion circuit, 14 is a delay amount determining circuit, 16 is a delay circuit, 16 is an address gate signal,
jumping signal.

A timing signal generation circuit that generates timing signals such as recording gate signals. 17.18 is the delay amount monitor signal,
Reference numeral 19 indicates a reference signal generated by detecting a sector mark or a one-rotation signal of the disk, and 2° indicates a position signal indicating the position of the sb optical system (with the optical disk as a reference). Reference signal 1
9 is the waveform shown in FIGS. 2(b) to (d), for example, and (b)
Assume that is an ideal waveform.

(,) and (C), (a) and (d) are the relationships when the optical system is located at the outer circumference or inner circumference of the optical disc, respectively.

Compared to the ideal waveform (in the ideal waveform), (c+) and (d) are temporally advanced by T1 and T2. First, the reference signal 19 is sent to the delay amount setting circuit 1o at the outer circumference of the optical disc.
The delay amount setting circuit 1o is adjusted so that (b) is outputted when the waveform shown in FIG. 2 (, ) is input and the same waveform is outputted as the monitor signal 7. T1 was delayed at this time.
A signal corresponding to the delay amount signal 24 is sent to the calculation circuit 12.
supplied to Similarly, the reference signal 19 when the optical system is moved to the inner circumference is as shown in FIG. 2(d), and the same signal is output as the monitor signal 18. By adjusting the delay amount setting circuit 11, the delayed T
A delay amount signal 25 corresponding to 2 is supplied to the arithmetic circuit 12. The arithmetic circuit 12 converts it into a voltage corresponding to the delay amount signal 24.25 and supplies it to the delay amount determining circuit 14 as the arithmetic signal 21.22 (corresponding to W and Z in FIG. 3).

Also, a position signal 2 indicating the position of the optical system with respect to the optical disk.
o is supplied to the position signal conversion circuit 13, converted to an appropriate voltage, and then supplied to the delay amount determining circuit 14 as a converted signal 26. The delay amount determining circuit 14 selects a delay amount corresponding to the converted signal 26, as shown in FIG. 3, and supplies the delay amount signal 23 to the delay circuit 15. In FIG. 3, the conversion signal 26 is selected as X (approximately the center of the disk).
, Y is selected as the corresponding delay amount. In this way, the amount of delay changes sequentially depending on the position of the optical system. The delay circuit 16 delays the reference signal 19 according to the delay amount signal 23 and supplies it to the timing signal generation circuit 16 .

As described above, when the traveling direction of the optical system does not intersect with the center of the optical disk, an accurate reference signal can be generated no matter where the optical system is moved, and as a result, an accurate timing signal can be generated. Less time is spent installing the system and transfer motor.

The case where the reference signal is temporally ahead of the ideal waveform (FIG. 2(b)) has been described above, but the case where it is delayed by T3 as shown in FIG. 2(-) is also possible.

83 in FIG. 2(,) is delayed by T3 with respect to $1 of the ideal waveform (b), but is advanced by T4 with respect to S2. Therefore, the optical system is on the periphery.

If they correspond to (C) and (d) located on the inner periphery, the same results as above can be obtained by shifting by (T1+T3+T4) and T4, respectively.

Further, as shown in FIG. 4, the timing signal generation circuit 16
The output may be input to the delay circuit 15. In other words, the same result as above can be obtained even if the timing signal is shifted without delaying the reference signal.

FIG. 5 is a block diagram showing a second embodiment of the optical disc device of the present invention, and FIG. 6 is a waveform diagram of the main parts.

27 and 28 are delay amount setting signals for the microcomputer, 29 is an address gate which is a type of timing signal, and 3o is a delayed reference signal. Delayed reference signal 3 in FIG.
address gate 2 based on o (corresponding to FIG. 6(e))
9 (Fig. 6 (corresponding to Φ)) is generated.The delay amount setting signal 27. If you try to read the address part shown in (-) using this gate signal, the read cine function will be reached in (f) (because the gate is misaligned with the address part).
, (b), and (C) are the limits of reading. If the delay amount is changed sequentially, (b), (C), (d)
, (f) is not distinguishable, T5/2 in the front and back direction.
It is also possible to obtain an ideal address gate (d) with a margin of .

Therefore, the delay amount can be set whether the reference signal is ahead or behind. Further, as in the first embodiment, the timing signal generation circuit 1θ is replaced by the delay circuit 16.
The same goes for placing it in front of . As described above, an accurate reference signal can be generated no matter where the optical system is moved, and as a result, an accurate timing signal can be generated, and the time required for installing the optical system and the transfer motor can be reduced.

Effects of the Invention As described above, according to the present invention, the time required for adjusting the optical system and the transfer motor can be reduced, and even if the optical system for reproducing data signals is moved to the inner or outer circumference of the disk, it can be moved to any position. However, it is possible to generate accurate timing signals and is extremely useful.

[Brief explanation of drawings]

1 and 4 are block diagrams of an optical disk device according to the first embodiment of the present invention, FIG. 2 is a waveform diagram of main parts for explaining the device, and FIG. 3 is a diagram showing the optical system position of the device and its location. FIG. 6 is a characteristic diagram showing the amount of delay; FIG.
8 are a block diagram and a waveform chart of essential parts of a conventional optical disc device. 1... Optical disc, 2... Optical system, 3
...Transfer motor, 4...Photo sensor, 10, 11...Delay amount setting circuit, 12...
... Arithmetic circuit, 13 ... Position signal conversion circuit, 14 ... Delay amount determination circuit, 15 ...
Delay circuit, 16...timing signal generation circuit. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 (') Same No. f, tA Ieso (change A fishing bow)
Inner circumference) Fig. 6 Fig. 7

Claims (1)

[Claims] an optical system that reads data signals recorded on the optical disk;
a reference signal generating means for generating a reference signal by detecting a sector mark, a one-rotation signal, etc. on the optical disk; and a reference signal generating means for shifting the generation of the reference signal depending on the position of the optical system or based on the reference signal. An optical disc device comprising: means for shifting a timing signal generated by a timing signal.