JPH0528866Y2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application The present invention relates to an improvement in a stereoscopic video disc record forming a double spiral recording track.

(b) Prior Art Video disc records that record high-quality video signals usually record MUSE signals and FM modulation. However, in the case of the MUSE signal, the horizontal synchronization signal is not negative polarity synchronization, and the synchronization cannot be easily separated. Therefore, the applicant proposed in Japanese Patent Application Laid-open No. 191589/1981 (H04N9/81) a high quality video disc record in which a constant frequency pilot signal is multiplexed on the reduction side of the FM/MUSE signal. According to this video disc record, it is possible to suppress jitter in the reproduced signal by detecting the jitter component from the reproduced pilot signal during reproduction.

The applicant previously proposed a double spiral stereoscopic video disc record for recording stereoscopic video signals in Japanese Patent Application No. 26229/1983. This stereoscopic video disc record records a left-eye video signal and a right-eye video signal simultaneously using two recording beams, thereby recording a right-eye recording track and a left-eye recording track in a double spiral. be. Therefore, if this stereoscopic video disk record is simultaneously reproduced using two reproduction beams, video signals for the left eye and right eye can be obtained simultaneously, and a stereoscopic video signal can be formed.

(c) Problems to be Solved by the Invention However, in the case of the above-mentioned stereoscopic video disc record, the two playback beams may reversely play back the right-eye recording track and the left-eye recording track during playback. Therefore, it is necessary to distinguish between the two recording tracks.

(d) Means for Solving the Problems Therefore, the present invention is characterized in that a pilot signal is multiplexed and recorded only on one side of the stereoscopic video disc record described above.

(E) Effect Therefore, according to the present invention, by determining from which pickup the reproduction pilot signal is being reproduced during reproduction, it becomes clear whether or not the corresponding pickup is reproducing the desired reproduction track. become.

(F) Embodiment The present invention will be described below with reference to an illustrative embodiment.

In this embodiment, a stereoscopic MUSE signal recorded by a 2-beam video disc recorder is played back by a 2-beam video disc player.
The figure shows a circuit block diagram of a video disc recorder. As is clear from this figure, the left-eye MUSE signal and right-eye MUSE signal forming the stereoscopic video signal are read out synchronously from the first and second MUSE signal sources 30 and 31. Each MUSE signal is the 1st and 2nd FM
The signals are input to modulation circuits 32 and 33 and subjected to FM modulation. FMMUSE signal for left eye is frequency multiplexed circuit 3
The FMMUSE signal for the right eye is input to the second optical modulation circuit 37. Frequency multiplexing circuit 35
frequency multiplexes the FMMUSE signal and the constant frequency pilot signal emitted by the pilot signal source 34,
The output is input to the first optical modulation means 36.
Each of the light modulation means 36 and 37 optically modulates the laser beam based on the input signal to form first and second recording beams, and irradiates the beam onto a position close to the video disc record 1 so as to overlap the record surface. A spiral recording track is formed (see Figure 3).

Therefore, video disk record 1 contains the left eye
A pilot signal is multiplex recorded only on the first recording track T1 on which the MUSE signal is recorded, and no pilot signal is recorded on the second recording track T2.

A double spiral stereoscopic video disc record in which a pilot signal is recorded only on the first recording track as described above is played back by a two-beam video disc player shown in FIG. First, the pickup 3 that scans the recording track by irradiating two reproduction beams onto the video disc record separately derives the reproduction outputs of two adjacent recording tracks and sends them to the first and second preamplifiers 4 and 5. supply The outputs of both preamplifiers 5 and 6 are the first and second
The signal is input to equalizers 6 and 7, and its frequency characteristics are corrected. Furthermore, each equalizer output is
1st and 2nd FM via high pass filters 8 and 9
Input to demodulation circuits 10 and 11 and reproduce two series
The MUSE signal is derived.

On the other hand, the outputs of the first and second preamplifiers 4 and 5 are input to an adder circuit 17 via first and second low-pass filters 12 and 13 for separating reproduced pilot signals. Therefore, the reproduced pilot signal obtained from either one is obtained from the adder circuit 17 and input to the pilot detection circuit 8. This pilot signal detection circuit 8 is composed of a bandpass filter, and transmits only the reproduced pilot signal of a predetermined frequency to the PLL circuit 2.
2 and is input to the phase comparator circuit 19. The phase comparison circuit 19 has the reference signal generated by the reference signal generation circuit 21 as another input, and inputs the obtained phase comparison output to the jitter mirror driver 20. Therefore, this drive output is input to the pickup 3 and drives a built-in jitter correction mirror (not shown). Also, the output of the PLL circuit 22 is
The signal is converted to a low frequency through the frequency dividing circuit 23 and then input to the frequency comparison circuit 24. This frequency comparison circuit 24 is connected to the second signal generated by the reference signal generation circuit 21.
The phase is compared with a reference signal, and the phase comparison output is input to the spindle motor drive circuit 25. Therefore, the spindle motor 2 is phase-locked to the low-frequency second reference signal and rotated at a constant speed, and the jitter correction mirror 2 corrects the jitter component of the reproduced output in accordance with the first reference signal that matches the pilot signal frequency. Absorbing.

The features of this embodiment are as follows. In this embodiment, the outputs of the first and second low-pass filters 12 and 13 are input to the first and second pilot signal discrimination circuits 14 and 15, respectively. Each of the pilot signal discrimination circuits 14 and 15 is composed of an envelope detection circuit and a comparator.
A discrimination output is issued from the side to which the playback pilot signal is input. Both discrimination outputs are input to a channel discrimination circuit 16. This channel discrimination circuit 1
The pickup 6 does not issue a jump output when a discrimination output is issued from the first pilot signal discrimination circuit 14, but issues a jump output only when a discrimination output is issued from the second pilot signal discrimination circuit 15. When this track jump output is issued, the pickup jumps by one track of each playback beam. Therefore, in the steady state,
A reproduced pilot signal is derived from the first low-pass filter 12, and the first FM demodulation circuit 1
A MUSE signal for the left eye is derived from the first FM demodulation circuit 10, and a MUSE signal for the right eye is derived from the second FM demodulation circuit 11.

(g) Effects of the invention Therefore, according to the invention, since the reproduction pilot signal is recorded on one of the recording tracks, the recording track can also be discriminated by the pilot signal, which is very effective.

[Brief explanation of the drawing]

Each of the figures shows an embodiment of the present invention; FIG. 1 is a circuit block diagram of a video disc recorder, FIG. 2 is a circuit block diagram of a video disc player, and FIG. 3 is a schematic explanatory diagram of a video disc record. Reveal each. 1...Video disc record, T1...1st
Recording track, T2...Second recording track.

Claims (1)

[Claims for Utility Model Registration] A three-dimensional video disc record in which a right-eye video signal and a left-eye video signal derived synchronously are simultaneously recorded on separate recording tracks to form a double spiral recording track. A stereoscopic video disc record characterized in that a constant frequency pilot signal is frequency-multiplexed recorded only on one recording track.