JPS5827892B2 - Information recorder playback device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a reproducing apparatus for an information recording disc, in which a main signal of an information signal on a capacitive recording disc is recorded on first and second adjacent disc surfaces of a main trunk section. In the first stage, information signals other than the above-mentioned main signals are recorded with a constant relative level relationship.
It is an object of the present invention to provide a reproducing device for an information recording disc, which can reproduce an information signal using a scanning needle as a change in capacitance with a good S/N ratio, stably and reliably by forming a second sub-track section and a second sub-track section. shall be.

Conventional devices that read and reproduce information signals as changes in capacitance control tracking by means of a guide groove on a disc-shaped recording medium in which information signals are recorded as changes in geometric shape at the bottom of a spiral guide groove. The pick amplifier detects the change in capacitance between the electrode provided on the scanning needle and the guide wheel layer of the recording medium by the scanning needle that slides while being moved, and changes the resonant frequency of the tuning circuit to detect the above information signal. As is well known, it is being played.

However, this type of conventional reproduction system has the following drawbacks.

■ Since the information signals to be recorded and reproduced are extremely wide-band signals such as video signals, it is necessary to keep the number of groove pinches on the recording medium to a few μm or less, and it is necessary to keep the width of the scanning needle tip in contact with and slide within the signal groove. Due to this, the contact area is limited, and the life of the scanning stylus and the recording medium is extremely short due to the high speed rotation of the recording medium.

■ In order to suppress the wear of the scanning needle, the needle pressure is set at 30 m! ? When the front and rear micro-pressures are applied, this causes a so-called needle-flying phenomenon to occur frequently.

(2) As the scanning needle wear progresses, the scanning needle tends to vibrate within the guide groove, making playback unstable and further accelerating the scanning needle wear.

(2) Due to the above-mentioned vibration phenomenon of the scanning needle, pressure is applied locally to the wall surface of the guide groove, and the surface coating is scraped off.

■Special playback such as still playback, slow motion playback, and high-speed cueing operations are impossible in principle due to the presence of the guide groove.

The present invention eliminates the above-mentioned drawbacks, and will be described below with reference to an embodiment thereof with reference to the drawings.

FIG. 1 shows a block system diagram of an example of a recording optical system for producing an information recording disc to be reproduced by the apparatus of the present invention.

In the figure, 1 is a light source, and the light beam emitted from this, for example, a laser beam, is split into many parts by a half mirror (a diffraction grating may also be used, but in this case, the laser beam is divided into many parts, each of which is divided separately as shown below). used for the purpose of

)2 is partially transmitted and supplied to the optical modulator 3, while
Part of it is reflected and further reflected by a reflecting mirror 4.5 and supplied to a rear light modulator 6.7, respectively.

On the other hand, 8 is the main information signal (
For example, frequency modulated (hereinafter referred to as FM) video signal)
At the input terminal, the main information signal coming from this is applied as a modulation signal to the optical modulator 3 via the driver 9, where it modulates the laser beam.

As a result, a modulated light beam modulated according to the main information signal is extracted from the optical modulator 3, and the half mirror
10 and 1T, respectively, and enter the objective lens 12, where the light is focused and irradiated with a focused photosensitive material 14 coated on a disc-shaped substrate 13 rotating at a predetermined speed. form the main trunk section.

At the same time, among the information signals to be recorded, the information signals other than the main information signal are in the form of a signal whose frequency or phase represents information, and are first and second sub-information signals having different frequency bands (for example, 500 kHz). The first and second modulated waves (obtained by angle-modulating the carrier wave frequency of IMHz and IMHz with signals with different information content) are modulated from the input terminal 15.16 to the optical modulator 6.7 via the driver 17°18. Applied as a signal.

Thereby, the first and second sub information signals are transmitted to the optical modulator 6.
7 as the first and second modulated sub-beams, reflected by the reflecting mirrors 19 and 20, and further reflected by the half mirrors.
io, ii.

The first sub-beam reflected by the half mirror 10 is
The second sub-beam transmitted through the half mirror 11 and reflected by the nozzle mirror 11 and the light beam from the optical modulator 3 pass through the objective lens 12 and are irradiated onto the photosensitive material 14.

At this time, the first and second sub-beams are directed from the objective lens 12 to the main beam from the optical modulator 3.
The optical path is adjusted as shown in FIG. 2 by a half mirror 10.degree. 11 and reflecting mirrors 19 and 20 so that a spot focused upward is formed at a position shifted to a predetermined trunk pinch.

Note that the scanning needle guide groove is not formed in the present invention, and is made into a peaceful surface.

The first and second sub-information signals (here, modulated waves) are recorded so that their relative level relationships are always constant.

Therefore, not only when the first and second modulated waves are recorded at the same level, but also when the levels of the first and second modulated waves are different from each other, the level ratio is always kept constant, and the relationship between them is As long as the following is satisfied, it is also possible to perform recording in such a way that the level gradually increases or decreases from the outer circumference to the inner circumference of the disk.

However, the recording levels of the first and 20th modulated waves are different from the recording level of the main information signal (usually a low level).

This is to reduce the beat disturbance that may occur between the reproduction signals of the main trunk and the sub-track during reproduction to a practical level.

Examples of information signals to be recorded include, for example, an FM color video signal as a main information signal, an angle-modulated audio signal as a sub information signal, or an FM color video signal as a sub information signal, or an FM color video signal as a sub information signal, or an FM color video signal as a sub information signal.
The latter is an FM luminance signal and an audio signal, the latter is an FM color signal, and one of the two side information signals is an FM carrier color signal or an FM audio signal, and the other is a pilot signal for color processing. (e.g. a continuous wave of a single frequency associated with the color subcarrier frequency) or even all multi-channel audio signals.
Various other combinations of signals are possible.

Note that the main information signal has a different frequency band than the first and second sub-information signals, and usually occupies a high frequency band.

The track pattern thus formed on the cutting master disc or on the surface of the pressed information recording disc of the present invention is as shown in FIG. 3 as a result.

In the figure, arrow 21 indicates the rotation (or running) direction of the information recording disk; Each trunk from y to tn+1 (n is an arbitrary positive integer) is formed in the main track part F where the main information signal is recorded as a change in geometric shape, and in each adjacent part of this main trunk part F. The information signals other than the main information signal among the information signals to be recorded are changed in frequency or phase in a signal form representing information (in this case, converted into first and second modulated waves) in a geometric shape. It consists of first and second sub-trunk parts FA and FA2, which are recorded as follows.

Note that the information recording disc to be reproduced by the apparatus of the present invention is reproduced by changing the capacitance.

Next, a reproducing apparatus for an information recording disc according to the present invention will be explained.

FIG. 4 is a block system diagram of an embodiment of an information recording disc reproducing apparatus according to the present invention, and FIG. 5 is a schematic diagram showing a schematic mechanism of an embodiment of the main part of FIG. 4.

The information recording disk having the trunk pattern shown in FIG. 3 recorded as described above is read as a change in capacitance by the sliding movement of the scanning needle.

That is, in FIGS. 4 and 5, reference numeral 22 denotes an information recording disc to be reproduced by the apparatus of the present invention having a trunk pattern as shown in FIG. Countless bits are formed.

This recording disk 22 is slid and rotated at a predetermined high speed with a scanning needle 23 driven under tracking control by a mechanism shown in FIG.

First, the tracking control drive of the scanning needle 23 will be explained with reference to FIG.
, a buffer member 39, and a bracket 40.
The sliding tip of No. 3 and the information surface on the information recording disk 22 are brought into stable contact with a low suppressing force.

Further, during operation, the signal pickup body 41 is configured to apply a low suppressing force to the scanning needle 23 in the vertical direction and to restrict movement in the horizontal direction.

43 is a so-called moving coil mechanism constructed based on the same operating principle as an audio speaker, and its internal structure consists of a permanent magnet, a driving coil, and a yoke (none of which are shown), and the coil portion is axially supported by a damper. A moving shaft 42 is formed, and this moving shaft 42 follows an arrow 44 according to the direction and magnitude of the current flowing to the drive coil.
The recording disk 22 is displaced by a predetermined amount in the radial direction shown in FIG.

Since the scanning needle 23 is attached to the moving shaft 42 via the signal pink amplifier body 41, the turntable 4 is scanned by the scanning needle 23.
The signal track on the information recording disk 22 placed on the disk 5 and rotated at high speed in the direction of arrow 46 is controlled at high speed in the track width direction (direction of arrow 44), which is perpendicular to the signal track.

The scanning needle 23, the signal pickup body 41, and the moving coil mechanism 43 are mounted on a transfer mechanism (not shown) in the radial direction of the recording disk 22 (arrow 47) during reproduction.
direction) at a slow speed synchronized with the rotation of the recording disk 22.

Due to the scanning of the scanning needle 23 described above, the change in capacitance formed between the pick-amplified electrode of the scanning needle 23 and the recording disc 22 is caused by the change in the geometrical shape of the recording disc 22. In the figure, the signal is converted into an electrical signal by a detection circuit 24 consisting of a tuning circuit, a detection circuit, and the like.

The output signal of the detection circuit 24 passes through a preamplifier 25, a bandpass filter (or high-pass filter) 26, and a bandpass amplifier 27.2.
8, respectively.

The high-frequency reproduced main information signal reproduced from the main trunk section F is converted into a P wave by the bandpass filter 26, and this signal is supplied to the signal processing circuit 29 where it is demodulated (signal processed) to the original information signal and sent to the output terminal 30. guided by.

On the other hand, the sub-trunk section F is
The first and second modulated waves of different frequency bands reproduced by AI and FA2 are separated and amplified, respectively, and then supplied to detectors 31 and 32, where they are envelope-detected and reproduced. The magnitude of the level is modulated to the magnitude of the direct light voltage level and is further applied to the differential amplifier 33.

The differential amplifier 33 detects the direction and magnitude of trunk deviation of the scanning needle 23 by comparing the polarities and levels of the two human input signals from the detectors 31 and 32, and moves the output signal in the direction to correct this. Feedback is applied to the coil mechanism 43 to cause the scanning needle 23 to move slightly and to constantly follow the scan over the main trunk portion F1 and the sub trunk portions FAI and FA2.

That is, the scanning needle 23 is constantly moved by a closed loop that operates so that the relative level relationship between the first and second modulated waves simultaneously reproduced from the sub-trunk section FAFA2 always maintains the same constant relationship as that at the time of recording. Stable and reliable tracking (open side).

In the present invention, the first and second modulated waves recorded in the sub-track sections F'A, F'A2 are used as reference signals for tracking control as described above, and the modulated waves of the information signal are used as reference signals for tracking control as described above. Since it is also a wave, it is supplied from the band amplifier 27.28 to the demodulator 34.35, where it is demodulated to the original information signal and taken out from the output terminal 36.3γ.

The demodulated main information signal from the output terminal 30 and the demodulator/information signal from the output terminals 36 and 37 are further subjected to signal processing to form the desired original information signal.

Therefore, the amount of information recorded can be increased compared to the amount of information recorded on a conventional information recording disk, or a margin can be provided when the total amount of information is the same as that of the conventional one.

For example, when playing back a record that records an FM luminance signal on the main track section F, an FM audio signal on one side of the sub-track section, and an FM carrier color signal on the other, the luminance signal band will be wider than before. Since it can be made wider, the S/N and resolution of luminance information are improved, and the S/N of color information is also improved, moiré is reduced and image quality is improved.

Furthermore, in the present invention, the patent application 1983-3 proposed earlier by the present applicant
Similar to the invention described in No. 8809, since there is no need to provide a needle guide groove on the information recording disk 22, the sliding area of the scanning needle 23 with the recording disk 22 can be made small, and therefore the scanning needle 23 and the recording disk The life of the scanning needle 22 can be extended, and even when the scanning needle 23 is used, the needle will not jump, and special reproduction can be performed for required scenes such as slow motion playback, still playback, high-speed position search, and high-speed cueing. It can be done arbitrarily and easily.

In FIG. 1, the track is recorded using a laser beam, but it goes without saying that other radiation such as an electron beam may also be used.

Further, the information recording disk reproducing apparatus according to the present invention is not limited to the above-mentioned embodiment, and in addition to the main trunk section F, one sub-track section on the adjacent first or second disk surface is provided. (
Therefore, it is theoretically possible to create an information recording disc and its reproducing apparatus that are provided with only FAl or FA2).

In this case, the recording relative level ratio of the recording signal of the main trunk section and the recording signal of one sub-trunk section, which have different frequency bands, is kept constant, and the two reproduced signals from the main trunk section and the sub-trunk section are (before demodulation) will be used as a reference signal for the tracking system.

The scanning needle 23 is caused to follow and scan the trunk width center line of the trunk consisting of the main trunk portion and the sub-truck portion.

As described above, the information recording disc reproducing apparatus according to the present invention has a main track section in which the main information signal is recorded as a change in geometric shape, and a sub information signal in the form of a signal whose frequency or phase represents the information. and has a frequency band different from the recording frequency band of the main information signal, and has a geometric shape on at least one of both sides of the main trunk portion, with a constant relative level relationship with respect to the main information signal. A device for reproducing recorded information signals of an information recording disc having a flat surface without a needle guide groove and having a sub-trunk part recorded as a change in the surface of the information recording disc. detecting that the capacitance formed between the electrode provided on the scanning needle sliding on the information recording disk changes in accordance with the geometrical shape change of the mold and the sub-trunk portion; From the reproduced signals thus obtained, the frequencies of the reproduced signals of the above-mentioned type and sub-trunk sections are selected and extracted separately, and the relative level relationship between the reproduced signals of the main trunk section and the reproduced signals of the sub-trunk section is determined as described above. At the same time, the scanning needle is driven in the trunk width direction of the main and sub-trunk sections at a high speed so as to be maintained in a constant relationship, and at the same time, the scanning needle is driven at high speed in the trunk width direction of the main and sub-trunk sections, and at the same time, from each reproduced signal from the main and sub-trunk sections extracted by selecting the frequency. Since it is configured to obtain the reproduction output of the main information signal and the sub information signal, the amount of recorded information can be increased, and when the amount of recorded information is the same as the conventional one, the S/N of the reproduced signal is improved compared to the conventional one. For example, if the main information signal is a frequency-modulated luminance signal and the information signal from the sub-track section is a frequency-modulated carrier color signal, the luminance signal band can be widened, so the resolution and It is possible to improve the S/N of the luminance signal, and there is no need to switch and control the polarity of the reproduction information signal from the sub-trunk section according to the rotation (or running) time of the recording disk during reproduction. This can be relatively simplified, and since there is no scanning needle guide groove that was required in the past, the sliding area of the scanning needle with the recording disk is made narrower, that is, the width of the base is wider than the electrode attached to the needle. Therefore, the life of the scanning stylus and recording disk can be extended, and even when using the scanning stylus, needle skipping does not occur, and special playback such as slow motion playback and still playback can be performed as desired. This method has a number of advantages, such as quick control response because tracking control is performed by displacing the scanning needle in the trunk width direction.

[Brief explanation of drawings]

Fig. 1 is a block system diagram of an example of a recording optical system for creating an information recording disc to be reproduced by an uninvented device, Fig. 2 is a diagram for explaining the optical path of the main part of Fig. 1, and Fig. 3 The figure shows a partially enlarged trunk pattern of an example of an information recording disc to be reproduced by the apparatus of the present invention, FIG. 4 is a block system diagram of an embodiment of the information recording disc reproducing apparatus of the present invention, and FIG. FIG. 5 is a perspective view showing a schematic mechanism of an embodiment of the main part of FIG. 4; 1...Light source, 2.10.11...＼＼mirror, 3
゜6.7... Optical modulator, 8... Main information signal input terminal, 12... Objective lens, 15.16...-1fil
J information signal information terminal, 23... Scanning needle, 26... Bandpass filter (or high-pass filter, 27.28... Bandwidth amplifier, 31° 32... Detector, 34, 35...
Sub information signal demodulator, 43...moving coil mechanism.

Claims (1)

[Scope of Claims] 1. A main trunk section in which the main information signal is recorded as a change in aeromorphic shape, and a sub information signal in the form of a signal whose frequency or phase represents information and which is different from the main information signal. It has a frequency band different from the recording frequency band, and has a constant relative level relationship with respect to the main information signal, and is recorded as a geometric shape change on at least one of both sides of the main trunk section. A device for reproducing recorded information signals of an information recording disc having a flat surface without needle guide grooves and having a sub-trunk portion with a stylus guiding groove, the scanning device sliding on the surface of the information recording disc. It was detected that the capacitance formed at the mj between the electrode provided on the needle and the information recording disk changes in accordance with the change in the S homological shape of the rack part in the above-mentioned upper and sub-1, and the obtained Select the frequencies of the above-mentioned upper and sub-trunk portion reproduction signals from among the reproduction signals and extract them separately.
The scanning needle is controlled at high speed in the track width direction of the ridge and the sub-trunk section so that the relative level relationship between the playback signal of the main trunk and the playback signal of the sub-trunk section is maintained at the constant relationship. Reproduction of an information recording disc characterized in that the reproduction output of the main information signal and the sub information signal is obtained from each reproduction signal from the ridge top and the sub trunk section which are selected and extracted at the frequency at the same time as being driven. Device. 2. The sub information signal is composed of first and second sub information signals having different frequency bands and having a constant relative level relationship, and the first sub information signal is the first sub information signal of the main trunk section. Claim 1, wherein the second sub information signal is recorded on one of the sub track sections on both sides, and the second sub information signal is recorded on the other of the sub trunk sections on both sides of the main trunk section. Information recorder playback device. 3. The information recording disc according to claim 1 or 2, wherein the main information signal is a frequency-modulated color video signal, and the sub-information signal is an angle-modulated audio signal. playback device. 4. The main information signal is a signal containing at least a frequency-modulated luminance signal, and the sub-information signal is a signal containing at least a frequency-modulated carrier color signal, or The information recording disk reproducing device according to item 2.