JPH06165098A - Optical disk player - Google Patents

Abstract

PURPOSE:To provide the optical disk player generating no shock noise during the output of reproduction sound at the time of special reproduction. CONSTITUTION:At the special reproduction, the oscillation output of a reference oscillator 22 for video with the fixed oscillation frequency corresponding to the synchronizing signal in the video signal read out from an optical disk 1 is selected, which is compared with a synchronizing signal by a phase comparator 7. The device is provided with a control circuit 29 selecting the oscillation output of a reference oscillator 24 for voice with the fixed oscillation frequency corresponding to a frame sink signal in voice signal data read out from an optical disk 1 and taking it as a clock signal to reproduce a voice signal. Based on the phase comparison output of the phase comparator 7, a spindle motor 3 is driven.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk player, and more particularly to an optical disk player for driving an optical disk based on audio data.

[0002]

2. Description of the Related Art Conventionally, in an optical disc player, an oscillation output of a first video reference oscillator having a fixed oscillation frequency corresponding to a frequency of a synchronization signal in a video signal read from an optical disc and an oscillation frequency phase-locked with the synchronization signal are used. The oscillation output of the second video reference oscillator, which is a controlled voltage controlled oscillator, is selectable, and the first fixed oscillation frequency corresponding to the frequency of the frame sync signal in the audio signal data reproduced from the optical disk is selected. The oscillating output of the audio reference oscillator and the oscillating output of the second audio reference oscillator, which is a voltage-controlled oscillator controlled to an oscillation frequency that is in phase synchronization with the frame sync signal, are selectable.

In the above-mentioned conventional optical disk player, during normal reproduction, the oscillation output of the second video reference oscillator is selected and the video signal is reproduced based on the oscillation output of the second video reference oscillator. The audio output of the first audio reference oscillator is selected, the audio signal is reproduced based on the oscillation output of the first audio reference oscillator, and the optical disk is rotationally driven based on the oscillation output of the first audio reference oscillator. Was.

Further, during special reproduction such as video search, the oscillation output of the first video reference oscillator is selected and the first
A video signal is reproduced based on the oscillation output of the video reference oscillator, the optical disc is rotationally driven based on the oscillation output of the first video reference oscillator, and the oscillation output of the second audio reference oscillator is selected. The audio signal is reproduced based on the oscillation output of the second audio reference oscillator.

[0005]

However, according to the above-mentioned optical disk player, the audio signal data reproduced from the optical disk during the special reproduction is disturbed, and the oscillation frequency of the second audio reference oscillator is also disturbed based on this disturbance. Then, since the oscillation output of the audio reference oscillator is used as a clock pulse in the signal processing circuit and D / A converter for audio reproduction, there is a problem that shock noise occurs during reproduction audio output. .

It is an object of the present invention to provide an optical disc player in which shock noise does not occur during reproduction audio output during special reproduction.

[0007]

The optical disk player of the present invention is synchronized with the oscillation output of the first video reference oscillator having a fixed oscillation frequency corresponding to the frequency of the sync signal in the video signal read from the optical disk. The first selection means for selecting one of the oscillation output of the second video reference oscillator controlled to the oscillation frequency phase-locked with the signal as a signal for reproducing the video signal, and read from the optical disc. The oscillation output of the first audio reference oscillator having a fixed oscillation frequency corresponding to the frequency of the frame sync signal in the audio signal data and the second audio reference oscillator controlled by the oscillation frequency phase-locked with the frame sync signal. Second selecting means for selecting one of the oscillating outputs for use as a clock signal for audio signal reproduction; and a second comparing means for comparing the phase of the output from the first selecting means with the synchronizing signal. Second comparing of the phase comparator, the frame sync signal and the phase with the output from the second selection means
Third phase selector, and one of the phase comparison output of the first phase comparator and the phase comparison output of the second phase comparator is selected.
Of the second selection unit and the first selection unit during the normal reproduction.
Of the video reference oscillator, the second selection means selects the first audio reference oscillator oscillation output, and the third selection means selects the second phase comparator output. In addition, during special reproduction, the first selection means selects the oscillation output of the first video reference oscillator, the second selection means selects the oscillation output of the first audio reference oscillator, and the third selection means. A control means for selecting the output of the first phase comparator is provided, and the spindle motor for driving the optical disk is driven based on the output of the third selecting means.

[0008]

According to the optical disk player of the present invention, the normal reproduction is the same as the conventional case, but in the special reproduction, the oscillation output of the first video reference oscillator is selected and the first reproduction is performed. The spindle motor is rotationally driven based on the output obtained by phase comparison of the oscillation output of the video reference oscillator and the synchronization signal, and the optical disc 1 is rotationally driven so as to match the oscillation frequency of the first video reference oscillator. Further, in this case, the selection by the second selection means does not change, and the oscillation output of the first audio reference oscillator, that is, the output of the fixed oscillation frequency is supplied as the clock signal for audio signal reproduction, and the audio signal is reproduced. Is reproduced, no shock noise is generated.

[0009]

EXAMPLES The present invention will be described below with reference to examples. Figure 1
FIG. 3 is a block diagram showing the configuration of an embodiment of the present invention.

The optical disc player of this embodiment reads an RF signal from the optical disc 1 by the pickup 2.
Audio signal data is extracted from the read RF signal by the low-pass filter 10. The extracted audio signal data is subjected to signal processing in the signal processing circuit 27, and D / A
The converter 28 converts the analog audio signal and outputs the analog audio signal.

From the audio signal data extracted by the low pass filter 10, a bit clock is reproduced in a bit clock reproducing circuit. The reproduced bit clock and audio signal data are stored in the frame sync generation circuit 1
2 and the frame sync signal is generated in the frame sync generation circuit 12.

The oscillation output from the audio reference oscillation circuit 24 having a fixed oscillation frequency corresponding to the frequency of the frame sync signal in the audio signal data reproduced from the optical disk 1 and the oscillation frequency which is in phase synchronization with the frame sync signal are controlled. The oscillation output from the audio reference oscillator 26, which is a voltage-controlled oscillator, is selected via the switch circuit 25, is supplied to the frequency divider 14, is divided, and is generated by the frequency division output and the frame generation circuit 12. The phase comparator 13 compares the phase of the frame sync signal
Only the low-frequency component of the phase comparison output of 3 is taken out through the low-pass filter 21 and supplied to the audio reference oscillator 26 to form a PLL loop, and the oscillation frequency from the audio reference oscillator 26 is controlled.

Further, the phase comparison output of the phase comparator 13 is passed through the low pass filter 16 to extract only the low frequency component,
The output of the low-pass filter 16 is output via the switch circuit 17. The output of the switch circuit 25 is the signal processing circuit 2
7 and D / A converter 28 as a clock.

The output of the switch circuit 17 is the PWM converter 1
9 and performs PWM conversion, and the PWM conversion output is supplied to the motor drive circuit 20, and the spindle motor 3 for rotating the optical disc 1 is driven by the output of the motor drive circuit 20.

On the other hand, a video RF signal is extracted from the read RF signal by the bandpass filter 4. The extracted video RF signal is demodulated by the video detector 5,
The sync separation circuit 6 separates the sync signal.

It consists of an oscillation output of a video reference oscillator 22 having a fixed oscillation frequency corresponding to the frequency of the sync signal in the video signal reproduced from the optical disk 1 and a voltage controlled oscillator controlled to an oscillation frequency phase-locked with the sync signal. One of the oscillation outputs of the video reference oscillator 23 is selected through the switch circuit 9 and supplied to the frequency divider 8 to be frequency-divided so that the frequency division output and the synchronization signal separated by the synchronization separation circuit 6 are phased. The phase comparison is performed by the comparator 7, and the phase comparison output of the phase comparator 7 takes out only the low frequency component through the low-pass filter 15 and supplies it to the video reference oscillator 23 to form a PLL loop. Control the oscillation frequency.

Also, the phase comparison output of the phase comparator 7 extracts only the low-pass component through the low-pass filter 18, the output of the low-pass filter 18 is supplied to the switch circuit 17, and is supplied to the PWM converter 19 via the switch circuit 17. Then, the spindle motor 3 is driven.

When the normal reproduction mode is instructed by a switch (not shown), the control circuit 29 controls the control signal a.
And b, the switch circuit 25 is switched to the output side of the audio reference oscillator 24, the switch circuit 9 is switched to the output side of the video reference oscillator 23, and the switch circuit 17 is switched to the output side of the low-pass filter 16.

When a special reproduction mode such as search is instructed by a switch (not shown), the control circuit 29
Switches the switch circuit 25 to the output side of the audio reference oscillator 24, switches the switch circuit 9 to the output side of the video reference oscillator 22, and switches the switch circuit 17 to the output side of the low-pass filter 18 by the control signals a and b.

In the present embodiment configured as described above, when the optical disc 1 with digital audio data is reproduced by normal reproduction, the switch circuit 25 causes the reference signal for audio to be transmitted by the control signals a and b from the control circuit 29. The output side of the oscillator 24 is switched to, the switch circuit 9 is switched to the output side of the video reference oscillator 23, and the switch circuit 17 is switched to the output side of the low-pass filter 16.

As a result, the optical disc 1 is drive-controlled based on the output of the audio reference oscillator 24, the optical disc 1 is rotationally driven so as to match the output frequency of the audio reference oscillator 24, and the signal processing circuit 27 and D / A converter 2
The output of the audio reference oscillator 24 is supplied to the audio signal 8 as a clock signal, the audio signal is reproduced, and shock noise or the like does not occur in the audio signal. Further, the video signal is reproduced with the oscillation output of the video reference oscillator 23 as a reference, and the image is not disturbed.

During special reproduction, the switch circuit 25 is switched to the output side of the audio reference oscillator 24 and the switch circuit 9 is switched to the output side of the video reference oscillator 22 by the control signals a and b from the control circuit 29. The switch circuit 17 is switched to the output side of the low pass filter 18.

When the optical disk 1 with digital audio data is reproduced by special reproduction such as search, the servo is disturbed by disturbance during special reproduction such as search, and the bit clock reproduction PLL is unlocked. Therefore, during the special reproduction, the signal for controlling the spindle motor 3 is switched to the phase comparison output of the phase comparator 7 which compares the oscillation output of the video reference oscillator 22 with the synchronization signal, that is, the signal from the video signal side. Be done.

That is, in this case, the output of the video reference oscillator 22 is selected by the switch circuit 9, and the phase comparison output obtained by phase comparison between the oscillation output of the video reference oscillator 22 and the synchronizing signal is selected via the switch circuit 17. Then, the optical disc 1 is rotationally driven by the spindle motor 3 so as to match the oscillation frequency of the video reference oscillator 22. In this case, the switch circuit 25 does not switch, and the oscillation output of the audio reference oscillator 24 is supplied to the signal processing circuit 27 and the D / A converter 28 as a clock signal, and the oscillation frequency of the audio reference oscillator 24 is fixed. Therefore, shock noise does not occur. Furthermore, since the audio is muted during special playback, no audio output is output.

In the case of an optical disc having no digital audio data, the control signal a selects the output of the low-pass filter 18 in the switch circuit 17, the switch circuit 9 selects the oscillation output of the video reference oscillator 22, and the switch circuit 25. The oscillation output of the audio reference oscillator 26 is selected. However, in this case, since there is no digital audio data on the optical disc 1, the problem of noise does not occur.

[0026]

As described above, according to the optical disk player of the present invention, in the case of special reproduction, the oscillation output of the first video reference oscillator is selected to be the oscillation output of the first video reference oscillator. The spindle motor is rotationally driven based on the output obtained by phase comparison with the synchronization signal, the optical disc 1 is rotationally controlled so as to match the oscillation frequency of the first video reference oscillator, and the oscillation output of the first audio reference oscillator, That is, since the output of the fixed oscillation frequency is maintained to be supplied as the clock signal for reproducing the audio signal, the optical disc is driven so as to match the oscillation frequency of the first video reference oscillator, that is, the fixed frequency. Moreover, since the clock signal for reproducing the audio signal also has a fixed frequency, the generation of shock noise in the audio signal is suppressed.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

[Explanation of symbols]

 1 Optical Disk 3 Motor 9, 17 and 25 Switch Circuit 29 Control Circuit 22 and 23 Video Reference Oscillator 24 and 26 Audio Reference Oscillator 27 Signal Processing Circuit 28 D / A Converter

Claims (1)

[Claims] 1. An oscillation output of a first video reference oscillator having a fixed oscillation frequency corresponding to the frequency of a sync signal in a video signal read from an optical disc and an oscillation frequency phase-locked with the sync signal. First selection means for selecting one of the oscillation output of the second video reference oscillator as a signal for video signal reproduction, and the frequency of the frame sync signal in the audio signal data read from the optical disc. The audio signal is selected by selecting one of the oscillation output of the first audio reference oscillator having a fixed oscillation frequency and the oscillation output of the second audio reference oscillator controlled to the oscillation frequency phase-locked with the frame sync signal. Second selection means for using as a clock signal for reproduction, a first phase comparator for phase comparison with the output from the first selection means and the synchronizing signal, and an output from the second selection means A second phase comparator for phase comparison with the frame sync signal, and a third selection means for selecting one of the phase comparison output of the first phase comparator and the phase comparison output of the second phase comparator, At the time of normal reproduction, the oscillation output of the second video reference oscillator is selected by the first selecting means,
Selection means to select the oscillation output of the first audio reference oscillator, third selection means to select the output of the second phase comparator, and the first selection means to select the first video during special reproduction. Control means for selecting the oscillation output of the reference oscillator for audio, selecting the oscillation output of the first audio reference oscillator by the second selecting means, and selecting the output of the first phase comparator by the third selecting means. An optical disk player, comprising: a spindle motor for driving an optical disk based on the output of the third selecting means.