KR810001140B1 - Signal regeneration apparatus - Google Patents

Abstract

A method of recording information signals comprises a spiral or circular typed recording track T, a recording disc D on which the demodulated signal is recorded in the direction of the width of the record track T, and a photobeam scanning disc d and photo detector which has a plurality of photobeam emitting device. The recording disc D and photobeam scanning disc d are placed oppositely each other and rotating respectively. The reflected beam from the recording track T is detected by the photo detector.

Description

Information signal playback device

1 to 19 are diagrams showing the parts of a recording and reproducing system including the embodiment of the present invention.

1 is a plan view showing an example of a recording disc which is a recording medium.

2 is a partially enlarged plan view of a recording track and a waveform diagram of a video signal corresponding to the recording track.

3, 4 and 5 are enlarged and enlarged cross-sectional views of different portions of the recording track, respectively.

6 is a process chart of the manufacturing method of the recording disc.

7 is a system diagram showing an example of a recording apparatus.

8 is a pattern diagram showing the configuration of signals recorded on a recording disc.

9 is a schematic diagram showing another part of the recording apparatus.

10 is a plan view showing an optical beam scanning disk of the recording apparatus of FIG.

11 is a schematic diagram showing an example of a playback apparatus according to an embodiment of the present invention.

FIG. 12 is a plan view showing an arrangement relationship between an optical beam scanning disk and a recording disk of the playback apparatus of FIG.

FIG. 13 is an enlarged plan view showing an optical beam scanning disk of the reproducing apparatus of FIG.

14 is an enlarged plan view of a portion of the reproducing apparatus optical beam scanning disc of FIG.

FIG. 15 is a system diagram showing a specific configuration of a video signal demodulation circuit of the playback apparatus of FIG.

FIG. 16 is a system diagram showing a specific configuration of an audio signal demodulation circuit of the playback apparatus of FIG.

Fig. 17 is a sectional view showing a part of another example of an optical beam scanning disk used in the reproducing apparatus.

18 is a plan view showing another example of an optical beam scanning disk used in another reproduction apparatus.

FIG. 19 is a partially enlarged plan view of the light beam scanning disc of FIG. 18; FIG.

The present invention relates to an information signal reproducing apparatus used for reproducing a recording disc in which information signals such as video signals are recorded at high recording density.

Recording of video signals, such as television signals, generally uses magnetic tape as a recording medium, and magnetic recording thereon.

However, magnetic tapes are disadvantageous in that they are troublesome to reproduce on the way, inconvenient to handle, poor in mass production of reproduction, and complicated and expensive in recording and reproducing apparatus.

Therefore, various methods have been proposed to use the recording disc as a recording medium to eliminate such defects and to record the video signal to form a spiral recording track thereon. The example method is briefly described below.

A spiral recording track is formed on a recording disk whose surface is mirror-finished, and a row of recesses are formed along a direction in which the recording track extends. This recessed portion is constant in depth and width, but its length and distance are changing depending on the level of the video signal. In this case, one frame of the television signal is recorded in one track of the recording track.

In order to reproduce the signal by the recording disk recorded in this way, the recording disk is rotated at a high speed (1500 R.P.M) so that the recording track is scanned with a light beam such as a laser beam along the extending direction thereof to detect the emitted light.

However, in such a recording method, the recording density of the information signal on the recording medium is not very high, and therefore, it becomes difficult to record a sufficient long time when recording a wideband information signal such as a video signal on the recording disc. In addition, since the recording disc must be rotated at high speed, it is very difficult to control the rotation speed and control the tracking by the light beam of the recording track.

In view of this, the present inventors can record information signals such as video signals and the like at high recording density at the same time, and at the same time, lower the rotation speed of the recording disk, and perform rotation control and playback tracking control of the recording disk during playback. The information signal recording method which can be made easy was considered.

It is an object of the present invention to propose an information signal reproducing apparatus capable of easily and reliably reproducing an information signal in a recording disc in which an information signal is recorded by such a recording method.

In the present invention, the recording disc of which a spiral or circular recording track is formed and the time-modulated modulation signal of the information signal in the width direction of the recording track is scanned and recorded every division and the width of the recording track of this recording disc. It has a light beam scanning disk and a light sensor having a plurality of light beam generating units arranged on the circumference at a corresponding pitch, and the recording disk and the light beam scanning disk are arranged opposite to each other and rotated separately so that each light of the light beam scanning disk The light beam from the beam generating portion is scanned in the width direction of the recording track of the recording disc so that the reflected light is detected by the light sensor so that the signal recorded on the recording disc can be read.

Next, an embodiment of the present invention will be described with reference to the drawings, but the entire information signal recording and reproducing system including the embodiment will be described separately, but the recording medium will be described first.

As a recording medium, a recording disc (for example, 30 cm in diameter) D as shown in FIG. 1 is used. This recording disc D is roughly identical to the current negative record board in appearance, except that the metal plate is plated on the same material (synthetic resin such as vinyl chloride) as the negative record board, and a metal transparent oxide film for protection is formed thereon. It is attached and is mirrored.

The recording disc D has a central hole 1, and a spiral recording track T wound on the surface thereof is formed several times. An example of the width of this recording track is 0.95 mm, and adjacent recording tracks are almost in contact with each other. (Of course, a gap may be provided between them.) For the convenience of explanation, the radial direction of the recording disk D is R and the circumferential direction is Q.

The recording disk D is a syringe lock of signals in the width direction of the recording track T, that is, in the radial direction R of the recording disk. In Fig. 2, this recording track T is shown enlarged. In addition, T 'and T' 'indicate recording tracks adjacent to the recording tracks T, but the detailed structure is the same, and the illustration is omitted.

This syringe lock is performed by arranging a plurality of spherical recesses in a row on each scan line (radial direction R), and changing the position or length (scan direction) of the recesses in the direction of the scan line. The width of the recess (in a direction orthogonal to the scanning direction, for example 1) and the depth (for example 1) are both roughly constant.

In this example, the pulsed phase modulated signal of the video signal, the front and rear pilot signals, and the pulse width modulated signal of the audio signal are recorded on the recording track T of the recording disc D. That is, as shown in FIG. 2, the pilot signal recording unit n ₁ , the video signal recording unit m, the rear pilot signal recording unit n _2, and the audio are sequentially sequentially on the one scanning line (radius R direction) from the left end to the right end as shown in FIG. 2. There is a signal recording section, and the recording width and recording position of each recording section are the same on each scanning line in the extending direction of the recording track T.

Each of the recording tracks T is enlarged and shown again in FIGS. 3, 4, and 5, wherein A in each drawing is a plan view thereof, and B in each drawing is a sectional view of a part thereof. 3 shows all of the recording track T and a part of the rear pilot signal recording sections n ₁ and n ₂ . 4 shows a part of the video signal recording unit m, and FIG. 5 shows a part of the audio signal recording unit a. In FIG. 3, the main parts h ₁ having the same length in the scanning direction, that is, in the radial direction R of the recording disc D, are arranged at equal intervals in parallel to the extending direction of the recording track T, that is, the circumferential direction Q of the recording disc D. Lined up. 4 also may be no In the main portion of the length h ₁ of 3 degrees gyeongwoogwa each column in the circumferential direction θ of each of its scanning lines eunghaeseo the level of each part of the video signal so that its position shifts in the radial direction R.

In Fig. 5, the length h is relatively longer than that of the parts h _shown in Figs. 3 and 4, and the length is arranged in one line in the circumferential direction θ in response to the level of each part of the audio signal for each scanning line.

Referring to FIG. 2, the width of the recording track T corresponds to one horizontal period (= 1H) of the NTSC system television signal st, and the video signal part S _T corresponds to the video signal recording part m of the recording track T. . The horizontal synchronizing signal corresponds to the entire pilot signal recording unit n ₁ of the recording track T at the end of the back porch of the television signal St, and the portion from the front porch to the middle of the horizontal synchronizing signal SH in the rear pilot signal recording unit n ₂ . The audio signal recording section a corresponds to a portion from the middle of the SH to the beginning of the back porch.

A video signal recording unit and m is, when writing to pulse phase modulation by the blood pulse phase modulated signal a carrier signal of about 4MKz a video signal, the column of the main portion ₁ h in the circumferential direction θ is the dog 254. In FIG. ₂ , f ₁ , f ₂ , f ₃ , and f ₄ indicate the group of scan lines corresponding to the radix and even peak of the NTSC system television signal, and F ₁ and F ₂ are the radix respectively. The group of scan lines corresponding to the frame consisting of the feed f ₁ , f ₃ and the even feed f ₃ , f ₄ is displayed, and the number of these scan lines is 525. In the recording disk D, its diameter is 30 cm, and recording and reproduction of a video signal of 1 hour or more is possible.

Such recording of the signal to the recording disc D can be performed directly on the material recording disc. However, since it cannot be mass-produced, a recording disc (stepper) is made in advance, such as an audio recording disc, and a plurality of recording discs are produced from this. You can duplicate D. How to make this recording disc will be explained based on FIG. A photoresist layer 5 is deposited on one surface as shown in FIG. 6B on the lacquer disc 2 of the lacquer disc 2 having the lacquer layer 4 on the aluminum substrate 3 as shown in FIG. 6B. do.

Next, as shown in FIG. 6C, the photoresist layer 5 is exposed to a predetermined pattern with a light beam, for example, a laser beam or an electron beam, as described below. When the exposed photoresist layer 5 is shaped, a cured photoresist layer 5 'having a large number of recesses identical to the Petereon of the recording track T to be actually obtained, as shown in Fig. 6D, is obtained. . A metal plating layer is formed on the photoresist layer 5 'with a predetermined thickness. Moreover, when the lacquer disk 2 of FIG. 6d is peeled from this metal plating layer, the stapler 6 as shown in FIG. 6e is obtained. A plurality of recording discs D are duplicated by heat-pressing a material recording disc such as vinyl chloride with the istanper 6 and mirror-finished as described above. Next, on the basis of the recording apparatus of FIG. 7, the exposure method in response to the signal to be recorded by the photoresist layer 5 of the lacquer disc 2 in the process of FIG. 6C (that is, indirectly, the recording disc). Recording method in D). In Fig. 7, (2) is a lacquer disk, which is placed on the turntable (8). (9) shows a cathode ray gun that generates an electron beam for exposing the photoresist layer (5) of the lacquer disk (2), and (10) places the electron beam on the lacquer disk (2) and writes the track. It is a deflection coil for deflecting only the width (for example, 0.95 mm). The recording of a signal by exposure to the lacquer layer of the lacquer disk 2 forms a spiral recording track from the outer circumference to the inner circumference and at the same time makes the recording speed in the extending direction of the recording track constant. For this reason, the cathode key 9 and the deflection coil 10 are fixed, and the turntable 8 is gradually moved in the direction of the arrow 12 from the state of illustration, and the rotation speed of the turntable 8 is synchronized with the movement. You need to speed up slowly.

Next, the driving means 13 of the turntable 8 for this purpose will be described. The tire 14 is brought into contact with the rear surface of the turntable 8 and the tire 14 is rotated at a constant speed (for example, a linear speed of 15 mm / sec) by the motor 15. On the other hand, the turntable 8 is attached to the moving box (gearbox) 16 having the roller 16a by the shaft 8 as a rotating material. A worm is formed in the shaft 8a of the turntable 8, and a worm gear 18 which is combined with the worm is provided, and the worm gear 18 is screwed to the feed screw 19. This feed screw 19 is normally fixed but was to be rotated by the motor 20 when returning the turntable 8 to its previous position.

When the tire 14 is rotated by the motor 15 in the turntable driving means 13, the turntable 8 rotates by this. The worm gear 18 is rotated by the rotation of the turntable 8 so that the moving box 16 moves in the direction of the arrow 12 together with the turntable 8. In addition, in response to the movement of the turntable 8 in the direction of the arrow 12, the rotation speed of the turntable 8 gradually increases. The range of the rotation speed is 1.03 ~ 3.0 PRM for the lacquer disc of 30cm in diameter (but used for recording up to 10cm in inner circumference). In other words, the recording speed in the extending direction of the recording track becomes constant. After the turntable 8 moves in the direction of the arrow 12 and the exposure recording of the lacquer disc 2 by the electron beam is completed, the feed screw 9 is rotated by the motor 20 to rotate the box ( 16 is rapidly moved together with the turntable 8 in the opposite direction to the arrow 12. At this time, the tire 14 is separated from the turning table 8. Next, a description will be given of a recording circuit system required for recording signals in the lacquer layer of the lacquer master 2. In Fig. 7, reference numeral 22 denotes this recording circuit system and reference numeral 22a denotes the video signal recording circuit system 22b denotes the audio signal recording circuit system. First, the video signal recording circuit system 22a will be described. Tv is an input terminal of a composite video signal (television signal) to be recorded, and the composite video signal supplied to the input terminal tv is supplied to the synchronization signal removing circuit 25. The front horizontal and back porches of the supplied horizontal synchronizing signal are removed, and only the feed video signal is taken out and supplied to the pulse modulation circuit 26. In this case, the pulse modulator 26 is a pulse phase modulator circuit. A reference numeral 27 denotes a carrier oscillator for supplying a carrier signal to the pulse modulator circuit 26. It is a pulse oscillator. The carrier oscillator 27 is locked by the horizontal synchronization signal separated by the synchronization signal separation circuit 28 from the composite video signal supplied to the input terminal tv. From this pulse modulation circuit 26, as shown in FIG. 8, the pulse modulation phase modulation signal Sm phase-modulated with the video signal of the carrier pulse signal from the carrier oscillator 27, and all of the unmodulated carrier pulse signal, and The rear pilot signals Sn ₁ , Sn _2, and the like are obtained every one horizontal period (= 1H).

Next, the audio signal detonation circuit system 22b will be described. ta is an audio signal input terminal, to which an audio signal relating to the video signal is supplied, which is supplied to the gate circuit 30 and sampled at the horizontal frequency of the video signal. Numeral 31 denotes a circuit for forming a gate signal for controlling the gate circuit 30, wherein a gate signal of a predetermined time width is produced with a predetermined phase therefrom based on a horizontal synchronization signal separated from the composite video signal. The audio signal sampled by the gate circuit 30 is supplied to the pulse modulation circuit 33. The band of the audio signal of the pulse width modulated signal output from the pulse modulation circuit 33 is about 7.5KH. This pulse modulation circuit 33 is a pulse width modulation circuit. 34 is a carrier oscillator for supplying a carrier signal to the pulse modulation circuit 33. The carrier oscillator 34 is locked by a horizontal synchronization signal separated from the composite video signal.

The outputs of the two pulse modulation circuits 26 and 33 are supplied to the switching circuit (or the addition circuit 35) and the output thereof is supplied to the cathode gun 9. The cathode supplied to the cathode gun 9 As shown in FIG. 8, in one horizontal period (= 1H), the pilot signal Sn ₁ , the pulsed phase modulated signal Sm of the video signal, the rear pilot signal Sn _2, and the pulsed pulse width modulation of the audio signal are shown in FIG. 8. One continuous signal consisting of the signal Sa (in this case, 1H) is obtained, and the electron beam is modulated by the signal supplied to the anode cathode 9.

Next, the lacquer violation 2 will be described with reference to FIG. 9 by the recording apparatus in the case where it is exposed by the light beam, in particular by laser light. However, most of the recording circuit 22 similar to FIG. 7 will be omitted and FIG. The same reference numerals are attached to the corresponding parts and the duplicate explanation is omitted. Numeral 37 denotes a laser oscillator, in which laser light is modulated by an optical modulator (by correction automatic) 38 by an output signal of the switching circuit 35 of the recording circuit system 22. The modulated laser light is converted into an optical beam deflected by the optical non-scanning disk 39 on the lacquer disk 2 by the width of the recording track, and the lacquer layer of the lacquer disk 2 is exposed by the light beam. This optical beam scanning disk 39 is a disk (about 75 mm in diameter) having a plurality of small holes 42 arranged at equal intervals on the circumference (concentric with the rotation center) as shown in FIG. 10, and the motor 40 ) To make a constant rotation. The pitch of the small holes 42 of the optical beam scanning disk 39 is roughly the same as the width of the recording track, and its diameter is about 1.5 mu.

개이며, 이경우의 광비임 주사원반(39)의 회전수는 5400 R.P.M이다. 이 광비임 주사원반(39)은 유리원반에 비스무트의 얇은 증착막(蒸着膜)을 피착한 것을 모우터(40)에 부착하여, 레이저광의 펄스 가공에 의해 소공(62)이 천설되어 만들어진다.The coefficient of the small holes 42 is the number of integers, such as 525 of the number of horizontal scanning lines of the NTSC system television signal, for example,

In this case, the rotation speed of the optical beam scanning disk 39 is 5400 RPM. The optical beam scanning disk 39 is attached to the motor 40 by depositing a thin film of bismuth on a glass disk, and is formed by laying a small hole 62 by pulse processing of laser light.

Next, a method of reproducing the recording medium recorded as described above, that is, the recording disc, will be described. An example of a playback apparatus is shown in FIG. In this reproducing apparatus, the recording track T of the recording disc D is scanned in the width direction, that is, in the radial direction R thereof by an optical beam such as a laser beam, and optically detects the recesses h ₁ and h ₂ . . 45 is a turntable, on which the recording disc D is placed and rotated. Reference numeral 46 denotes a motor for rotationally driving the turntable 45, 47 a capstan attached to the pulley of the motor 46, and the capstan 47 is connected to the edge of the turntable 45. It is inverted. Reference numeral 48 denotes a sub circuit for controlling the rotation of the motor 46, and 49 is a reference signal oscillator for supplying a reference signal to the sub circuit 48.

Denoted at 51 is a laser oscillator. That is, the laser beam is converted into the optical beam deflected by the optical beam scanning disk d by the width of the recording track T through the optical condenser 52, and through the half mirror 53 and the lens 54 of the optical beam, The recording track T is scanned by scanning in the width direction thereof. Reference numeral 56 denotes an optical sensor for detecting the reflecting tube on the light beam recording disk D through the half mirror 53.

개이며, 이 경우의 광비임 주사원반 d의 회전수는 5400 R.P.M이다. 이 광비임 주사원반 d의 직경은 75 mm정도이다. 그리고 광비임 주사원반 d의 외경은 작은 편이 두께가 얇으므로 회전에 의한 흔들림이 없어서 바람직하다. 이 광비임 주사 원반 d는 유리원반에 비스무트의 얇은 증착막을 피착시킨 것을 모우터(57)에 부착하여, 레이저광의 펄스 가공에 의해서 소공 P₀,P₁,P₂ㆍㆍㆍ가 천설된다.In Fig. 12, the recording disk D and the light beam scanning disk d opposed thereto are shown in plan view. The optical beam scanning disk d is enlarged and displayed in FIG. 13, and the optical beam scanning disk d is enlarged again in FIG. 14 to show a part of the optical beam scanning disk d. It is a disk having a plurality of small holes P ₀ , P ₁ , P _2... Arranged at intervals, and the motor 57 makes a constant rotation. The pitches of litigation P ₀ , P ₁ , P _{2... Of the} optical beam scanning disk d are roughly the same as the width of the recording track T, and the diameter thereof is, for example, 1-1.5 µ abutment. The number of small pores P ₀ , P ₁ , P _2...

In this case, the rotation speed of the light beam scanning disk d is 5400 RPM. The diameter of the light beam scanning disk d is about 75 mm. The smaller the outer diameter of the light beam scanning disk d is, the thinner the thinner the thinner the thinner the thinner the disk. This optical beam scanning disk d adheres to the motor 57 by depositing a thin film of bismuth on a glass disk, and forms pores P ₀ , P ₁ , P _{2... By} pulse processing of laser light.

The laser beam irradiated from the laser oscillator 51 onto the optical beam scanning disk d has a length e in the circumferential direction of the optical beam scanning disk d, as indicated by g in FIG. 14 when the magnification of the lens 54 is 1. ₁ is equal to the width of the recording track T, and the radial width e ₂ in the radial direction is a light beam having a cross section slightly larger than the small pores P ₀ , P ₁ , P ₂ .

The laser oscillator 51, the optical thin film condenser 52, the half mirror 53, the lens 54, the optical sensor 56, and the motor 57 are integrally formed to move from the outer circumference of the recording disc D toward the center. (The driving means is not shown in the drawing.) The light beam scans the recording track T of the recording disc D so that its linear velocity in the extending direction is constant, so that the turntable 45 has a light ratio. As you move from the outer circumference on the recording disc D to the inner circumference, it rotates quickly. Therefore, the rotation speed of the turntable 45 is 1.03 R.P.M when the optical beam is scanning its outer circumference (approximately 30 cm in diameter) and 3.0 R.P.M when its inner circumference (about 10 cm in diameter) is being scanned.

In this reproducing apparatus, a row of recesses h ₁ and h ₂ on the scanning line with the recording track T of the recording disk D is scanned by the light beam from the small hole P ₀ with the optical beam scanning disk d, and thus from the small hole P ₁ of the heart. By means of the light beam, rows of recesses h ₁ .h ₂ on the scanning line following the recording track T are scanned.

In this case, the light beam is focused on the surface (mirror surface) of the recording disc D, and is not focused on the bottom surfaces of the recesses h ₁ and h ₂ . For this reason, the reflected light is obtained only when irradiating the surface of this light beam recording disk D, and this is detected by the light sensor 56 via the half mirror 53. As shown in FIG. Then, from the optical sensor 56, a reproduced signal of the signal recorded on the recording track T of the recording disc D is obtained, which is supplied to the video signal demodulation circuit 59 and the audio signal demodulation circuit 60 to output each of the signals. Demodulated video and audio signals are obtained at the terminals 59a and 60a, respectively. In addition, the specific structure of these demodulation circuits 59 and 60 is demonstrated next. A part of the output of the video signal demodulation circuit 59 is supplied to the synchronous separation circuit 62 so that its vertical synchronization signal is separated, and this is supplied to the sub circuit 48 to provide a reference from the reference signal oscillator 49. Compared with the signal, the reproduction of the signal and the rotation of the recording disc D are synchronized.

Next, the video signal demodulation circuit 59 will be described with reference to FIG. Reference numeral 59b is an input terminal, to which the same signal as shown in Fig. 8 is supplied, which is supplied to the limiter circuit 65 and the detection circuit. The detection circuit 66 is a diode and a bandpass filter. The detection circuit is formed, and the output of the detection circuit 66 is supplied to the waveform shaping circuit 67 to form a waveform to obtain a horizontal synchronizing signal.

The output of the limiter circuit 65 is supplied to the gate circuits 69 and 70 which extract the front pilot signal Sn ₁ and the rear pilot signal Sn ₂ , respectively. The gate signals supplied to these gate circuits 69 and 70 are made by the gate signal generation circuit 71 based on the obtained horizontal synchronizing signal.

Reference numeral 73 denotes a synchronous detection circuit in which the output of the limiter circuit 65 is supplied to detect the video signal, but the carrier signal of the pulsed phase modulated signal Sm of the video signal used for the detection is obtained as follows. That is, the variable frequency oscillator 75 is provided so that the full pilot signal Sn ₁ obtained from the gate circuit 69 is supplied to the variable frequency oscillator 75, which is subjected to frequency control (injection lock). At the same time, a phase comparison circuit 76 is provided, in which the output of the variable frequency oscillator 70 and the rear pilot signal Sn _{2, which} is the output of the gate circuit 70, are compared in phase. The comparison output is supplied to the variable frequency oscillator 75, so that phase control is performed. The output of the variable frequency oscillator 75 is supplied to the synchronous detection circuit 73 through an ideal phase 77 of 90 degrees.

The phase-detected video signal output to the synchronous detection circuit 73 is supplied to the addition circuit 79 through the low pass filter 78, and the horizontal synchronization signal from the waveform shaping circuit 67 is added thereto. A composite video signal is obtained at the output terminal 59a.

Next, the audio signal demodulation circuit 60 will be described with reference to FIG. 16. Reference numeral 60b is an input terminal, and a signal similar to that shown in FIG. It is supplied to the gate circuit 81 which makes out the pulse width modulation signal Sa. The gate signal supplied to this gate circuit 81 is made based on the horizontal synchronizing signal from the waveform shaping circuit 67 in FIG. 13 in the gate signal forming circuit 82. As shown in FIG. 60c is an input terminal of the horizontal synchronization signal. The output of the gate circuit 81 is supplied to the demodulation circuit 84 through the waveform shaping circuit 83. This demodulation circuit 84 is a pulse width demodulation circuit. The demodulated audio signal obtained at the output side of the demodulation circuit 84 is obtained at the output terminal through the low pass filter 86.

Next, a modification of each part of the above-described information signal recording and reproducing system will be described. The recording track T of the recording disk D may be formed by a plurality of concentric circles, not spiral. All of the signals recorded on the recording disk D and the rear pilot signal may be one of them.

The video signal recorded on the recording disc D may be its pulse width modulated signal. However, the pulsed phase modulated signal is suitable for wideband transmission.

In the reproducing apparatus of FIG. 11, if the incident angle of the light beam scanning the recording disc D is set to 90 degrees or less so that the half mirror 53 is not provided in the passage of the incident light, the incident light is effectively used for scanning the recording disc D as much. .

A modification of the light beam scanning disk will be described based on FIG. The optical beam scanning disk d of this example is provided with the lens 54 in FIG. 11 in each small hole. That is, the lens 91 is formed integrally or separately on one surface of the transparent disk 90 such as glass, and the light shielding layer 92 is formed on the other surface of the transparent disk 90, and at the same time, The small holes 93 are formed at positions corresponding to the lenses 91. These small pores 93 and the lens 91 are arranged corresponding to the small pores P ₀ , P ₁ , P _{2... Of the} light beam scanning panel d in FIG. 13.

The optical beam scanning disk d of FIG. 17 is manufactured as follows. In other words, the photosensitive film on the other side of the transparent disk 90 on which the lens 91 is formed is deposited, and the transparent disk 90 is rotated at a constant rotational speed, so that light from the pinhole by the scintillation device is applied to the lens ( Projected onto a photoresist film corresponding to 91 and exposed, and after that, the photoresist film is reversely developed to form a light shielding layer 92 having small pores 93. In this case, even if the position on the transparent disk 90 of the lens 91 is somewhat incorrect, the position of the suit 93 provided in the light shielding layer 92 can be easily adjusted to the position of the lens 91. The optical system is also simplified. (No relay lens or the like is required.) Moreover, the small holes 93 of the light shielding layer 92 do not have to be small (for example, a diameter of 5 µ), which is why the diffraction in the small holes 93 of the laser light is reduced. There is little loss by).

Although the above-described optical beam scanning disk d is for reproducing the video signal recorded on the recording disk D as it is, the optical beam scanning disk for reproducing the video signal as a still image will be described with reference to FIGS. 18 and 19. do. d 'denotes the optical beam scanning disk, and the small pores P ₀ , P ₁ , P _2... are the same as the small holes of the optical beam scanning disk d in FIG. 13 (this enables normal reproduction of a video signal). ), Small pores P ₀ ', P ₁ ', P ₂ '... are provided on a spiral wound inside the small pores P ₀ ', P ₁ ', P ₂ '. The pitches of these small pores P ₀ ', P ₁ ', P ₂ '... are roughly equal to the width of the recording track T of the recording disc D. The number of these small pores P ₀ ', P ₁ ', P ₂ '... is equal to the opening 525 of the scanning line of one frame of the television signal of the NTSC system.

In the case of reproduction of this still image. The turntable 45 on which the recording disc D is placed is placed in a stationary state, but the optical beam scanning disc d 'is rotated at a rotational speed of 1800R, P, M. In this case, the laser light from the laser oscillator 51 has a length e _{1 in} the circumferential direction of the light beam scanning disk d 'equal to the width of the recording track T, as shown in FIG. If e ₂ is the pore width P ₀ ', P _1', the minimum cross-sectional dimension to cover the whole of the P ₂ 'and and and. Incidentally, other configurations of the reproducing apparatus in the case of still image reproduction are substantially the same as those in the above-described normal reproduction.

According to the present invention described above, a recording disc having a spiral or circular shape is formed, in which the time-modulated modulation signal of the information signal in the width direction of the recording track is injected by one segment, and corresponds to the width of the recording track of the recording disc. An optical beam scanning disc having a plurality of light beam generating units arranged on the circumference at one pitch, and having a light sensor, the recording disk and the optical beam scanning disc are arranged to face each other and rotate separately, The beams are scanned from the respective light beam generating units in the width direction of the recording track of the recording disc by the light beams, and the reflected light is detected by the light sensor so that the signals recorded on the recording disc can be read. A circular recording track is formed so that the information from the recording disk in which the time-modulated signal of the information signal in the width direction of the recording track is syringe-locked by one division. The can be easily and certainly play signal.

In addition, according to the present invention, since the plurality of light beam generating portions of the light beam scanning disk are each configured in the light transmitting portion, the recording tracks of the recording disk are scanned by the light beam obtained through the light transmitting portion from the light source. At the same time, the configuration is simplified, and the position of the light beam generating portion can be precisely defined.

In the above-described example, the recording pattern of the recording disc is a case in which the main portion is composed of main parts, but various optical patterns such as light pattern patterns can be used.

In addition, the information signal recorded on the recording disc can be a variety of information signals such as an audio signal and a data signal in addition to the video signal.

As the plurality of light beam generating units of the light beam scanning disk, point light sources such as, for example, light emitting diodes may be separately disposed at positions corresponding to the small pores of the above-described example.

Claims (1)

Spiral or circular recording tracks T are formed as shown in the figure and described above in the main text, and the time-axis modulation signals of the information signals in the width direction of the recording tracks T are scanned by one division. And a light beam scanning disk d and a light sensor 56 having a plurality of light beam generating portions arranged on the circumference at a pitch corresponding to the width of the recording track T of the recording disk D and the recording disk D. D and the light beam scanning disc d are arranged opposite to each other and are rotated separately and are scanned in the width direction of the recording track T of the recording disc D by the light beams from each light beam generating portion of the light beam scanning disc d, the reflected light The information signal reproducing apparatus, which is detected by the optical sensor (56) so that a signal recorded in the recording disc (D) is read out.

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