JPS595976B2 - Information recording method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording method for an information recording medium. By using it as a detection signal, it can reduce interference such as bead interference to the main information signal when recording signals other than video signals, and it can also make time axis error detection easier, and it can also record video signals. A fifth object of the present invention is to provide a recording method for an information recording medium that can obtain a time axis error detection signal with a good signal-to-noise ratio regardless of the situation.

Conventionally, in order to correct the time axis error, there is a method of controlling the speed of a turntable such as a video disc, or driving an arm stretcher to move a signal conversion element such as a scanning needle in the track scanning direction10. As such, when the recorded information is a video signal, a color burst signal or a horizontal synchronization signal can be used to detect a time axis error signal.

However, when using a color burst signal, the color burst signal may be interrupted during the vertical blanking period and the frequency may be too high, and when using a horizontal synchronization signal, the signal to noise ratio must always be kept sufficiently high. There were many problems, such as the fact that it was difficult to do this, and furthermore, if tracking was not achieved, none of the above signals could be retrieved.

Furthermore, if the 20 recorded information is an audio signal, since none of the above signals are present, another signal must be added. The present invention eliminates the above-mentioned drawbacks, and an embodiment thereof will be described below with reference to the drawings.

25 The present invention is designed to constantly obtain a time axis error detection signal with a good S/N ratio.
No. 38809 (see JP-A-52-123205)
This invention is based on one of the two or more inventions proposed in 2006, and uses the tracking control reference signal No. 30 for time axis error signal detection.

In other words, the above-mentioned invention proposed by the applicant is “
A plurality of reference 35 signals having different frequencies are respectively inserted and recorded in at least adjacent first and second information signal unrecorded portions of a track formed by recording an information signal on a recording medium, and the information signal is , an information signal recording system characterized in that a reference signal is recorded so as to be reproduced by a signal conversion means that scans and reproduces the recording medium during reproduction. FIG. 1 shows a block diagram of an embodiment of the method for recording an information recording medium according to the present invention.

As an example, a video disk in which the information signal is a video signal and the recording medium is a rotating recording disk (hereinafter referred to as disk) will be explained. In the figure, 1 is an oscillator that oscillates the color subcarrier frequency of the video signal to be recorded, for example 3.58 MHz, and is connected to down-down and multiplier circuits 2 and 3, a synchronization signal generator 5, and a video signal processing circuit. 7 respectively. The circuit 2 counts down the input frequency to n1/m1 (M, , n, are positive integers), and the circuit 3 counts down the input frequency to N2/M2 (M2, n2 are positive integers). Here, as an example, n1=N2=1, m
14, m2=6, the outputs of the circuits 2 and 3 are 894.9 KHz and 596.6 KHz, respectively.
These respective output signals (shown in FIGS. 3B and 3C) are supplied to a switching circuit 4, where the signals are alternately switched and output for each revolution of the disk to be recorded, depending on the output of the synchronization signal generator 5. and is modulated by a modulator 6. On the other hand, in the video signal processing circuit 7, the video signal to be recorded is subjected to signal processing together with the synchronization signal from the synchronization signal generator 5 and the oscillation output signal of the oscillator 1, and is converted into the signal shown in FIG. 3A. The signal is then supplied to a frequency modulator 8, where it is frequency modulated.

As a result, the video signal frequency-modulated by the frequency modulator 8 is recorded on the spiral or concentric tracks shown in FIG. In a portion of I, a single frequency signal of 6 seconds is recorded by the modulator 6 as a reference signal for tracking control, as shown in FIG.

Since a reference signal for tracking control is recorded on a disc recorded in this way, there is no need to specifically form a guide groove for a scanning needle for reproduction, and countless pits are formed on a disc with a flat surface. Ru.

Therefore, this makes it possible to increase the contact area between the scanning needle and the disk, thereby making it possible to extremely extend the life of the scanning needle and the disk. However, a needle guide groove may be provided as in the conventional case. Therefore, in the recording method of an information recording medium according to the present invention, the frequencies of a plurality of (i) signals recorded as tracking control reference signals are set to certain constant frequencies Mi and Nl, n2, . . . , Ni are arbitrary positive integers).

FIG. 2 shows a →u block diagram of a method for reproducing an information recording medium recorded according to the method of the present invention.

The three types of signals, the video signal and two single frequency signals picked up by the head 9, are supplied to a demodulator 10 and band filters 11 and 12, respectively, and the video signal demodulated by the demodulator 10 is sent to a sync separation circuit. The signal is supplied to a signal processing circuit 14 together with the synchronization signal separated by 13, where the signal is processed and converted into a video signal in the original signal form. On the other hand, since the center frequencies of the pass frequency bands of the band filters 11 and 12 are selected to be 894.9 kHz and 596.6 kHz, the 894.9 kHz and 596.6 kHz
The Hz signal is separated and supplied to one of the detection circuits 16 and 17 via the switching circuit 15, respectively.

Here, the polarity of the signal obtained as the tracking control reference signal differs every time the disk rotates, and the driving direction to the tracking control element is reversed every time the disk rotates.
The switching circuit 15 switches the input to the detection circuits 16 and 17 every rotation of the disk in response to a synchronization signal from the synchronization separation circuit 13. The two tracking control reference signals are envelope-detected by detection circuits 16 and 17 and converted into DC voltages, and then supplied to a differential amplifier 18 .

The tracking control signal of polarity and level obtained from the differential amplifier 18 according to the track deviation direction and deviation position controls a servo mechanism (not shown) so that the head 9 constantly tracks and scans the track. make it work. Further, the output tracking reference signals of the band filters 11 and 12 are -2-, hill (1,,1).

．． k,. k2 is a positive integer),
They are added to multiplier circuits 19 and 20, respectively. As an example, if k1=K2=1, 21=3, and 12=2, signals of the same frequency of 298.3 kHz are obtained from the down-down and multiplier circuits 19 and 20, respectively. Since these signals are frequency-modulated by the time axis error component, they are supplied to a detection circuit 21 to detect the error signal, and further passed through a driver 22 to drive the rotation speed of the turntable or the arm stretcher. In this way, the down-down and multiplier circuits 19 and 2
Since the output frequency of 0 is the same and both frequencies are used, even if tracking is lost for some reason and only one of the tracking control reference signals is reproduced, the time axis error signal can be detected without any problems. Can be done. Note that the present invention is not limited to the above embodiments, and for example, n1=3, n2=2, m1=M2=1
3, k1 = K2 = 1, 1, -3, 12 = 2, in which case the tracking control error signals are 8, respectively.
The frequencies are 26.0 kHz and 550.7 kHz, which are three times and twice the horizontal scanning frequency of 35/2, respectively.

NlKln2K2 can take an integer other than this, and it is sufficient to satisfy the relationship: 1×-[Me[×1Mlllm9l2.

According to this method, time axis errors can be detected using the same signal even on disks on which audio signals are recorded. Furthermore, the invention is not limited to disks, and can also be applied to cylindrical recording media. Furthermore, the tracking control reference signal may not have a single frequency but may have a certain band.
Furthermore, in the above embodiment, the reference signal is inserted and recorded between tracks provided with a guard band, but in a recording body with a track pattern without a guard band, the information recording track is centered at a position different from the scan center position. By inserting and recording a reference signal into the track formed by
It is possible to achieve the intended purpose.

As described above, the method for recording an information recording medium according to the present invention is based on a recording medium in which information signal recording tracks are arranged adjacently on a track formed with its center at a position different from the track scanning center position. , a plurality of reference signals having different frequencies are inserted and recorded, and the plurality of reference signal frequencies are separated by a signal conversion means that scans the recording medium during reproduction. The frequencies of the plurality of reference signals with different frequencies are selected and recorded so that a time axis error signal can be obtained by detecting the signals that have been subsequently down-loaded and multiplied to have the same frequency. Therefore, the plurality of reference signals mentioned above can be used as signals for detecting the time axis error between the signal converting means and the information recording medium, and as a result, the time axis error can be detected regardless of the recorded signal. It is possible to suppress interference to the information signal, it is inexpensive, and it is possible to detect time axis errors even when tracking is not achieved, compared to the conventional case of detecting time axis errors using color burst signals. Although the signal was interrupted during the vertical blanking period, this does not occur, making it easy to detect time axis errors, and since the reference signal is not demodulated, there is less time delay and less distortion, which is useful even when recording video signals. It has many features such as being able to obtain a time axis error detection signal with a good signal to noise ratio.

[Brief explanation of drawings]

FIG. 1 is a block system diagram of an embodiment of the method for recording an information recording medium according to the present invention, FIG. 2 is a block system diagram of an example of a reproducing system for an information recording medium recorded by the method of the present invention, and FIG. A-C and D are a partial enlarged plan view of a signal waveform diagram and a track pattern of each part in FIG. 1, respectively. 1... Oscillator, 2, 3, 19, 20...
・Down-down, multiplier circuit, 4, 15... switching circuit, 6, 8... modulator, 9... head, 10... demodulator, 11, 12...
band filter, 14...signal processing circuit, 16,
17, 21...detection circuit, 18...τ
Differential amplifier.

Claims (1)

[Claims] 1. A plurality of reference signals having different frequencies are applied to a reference signal track formed with its center at a position different from the scanning center position of the track on a recording medium in which information signal recording tracks are arranged next to each other. The plurality of reference signals are inserted and recorded, and the frequencies of the plurality of reference signals reproduced by a signal converting means that scans the recording medium during reproduction are separated, and then down-done and multiplied, respectively. An information recording body characterized in that the frequencies of the plurality of reference signals having different frequencies are selected and recorded so that a time axis error signal can be obtained by detecting each signal having the same frequency. How to record.