JPH04205858A - Recording method for wide-band image information - Google Patents

Abstract

PURPOSE:To enhance an image quality by a method wherein image information whose band is twice wider than the band width of a recording and reproducing system can be recorded. CONSTITUTION:A recording signal such as image information or the like is input from a recording signal input terminal 1; it is frequency-modulated by using a frequency modulator 2. The recording signal which is frequency- modulated is further halved by using a divider 3; a signal covering two waves is changed to one wave and recorded at a pitch edge in a recording and reproduction system 4 such as an optical disk or the like. At the time of reproduction, the signal recorded on the recording and reproduction system 4 is doubled by using an edge detector 5; after that, it is demodulated by using a frequency demodulator 6; the image information which is reproduced is output from an output terminal 7. Consequently, the image information whose band is wider than the band width of the recording and reproduction system can be recorded. Thereby, an image quality can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] This description relates to a method for recording and reproducing recording signals such as image information on a recording/reproducing system such as an optical disk.

[Conventional technology]

Conventionally, the method of recording and reproducing recording signals such as image information on a recording/reproducing system such as an optical disk is based on the FM modulation/demodulation method using a magneto-optical disk such as MAG-88-208PP, 29-34 magneto-optical disk. As stated in the record, FM modulation and demodulation was used. In this FM modulation/demodulation system, recording/reproduction cannot be performed unless the bandwidth of image information, etc. and the deviation in FM modulation/demodulation are smaller than the bandwidth of the recording/reproducing system. For this reason,
FM recording of image information wider than the bandwidth of the recording/reproducing system was not possible.

[Problem to be solved by the invention]

Since the above conventional technology cannot perform FM recording of image information with a bandwidth wider than the bandwidth of the recording/reproducing system, it is necessary to record and reproduce image information of higher image quality, that is, a signal with a bandwidth wider than the bandwidth of the recording/reproducing system. I couldn't.

An object of the present invention is to make it possible to record image information in a wider band than the bandwidth of a recording/reproducing system, and to improve image quality.

[Means to solve the problem]

In order to achieve the above object, in the present invention, as a method of recording and reproducing a recording signal such as image information, a recording signal after FM modulation is divided into half by a divider. This recording signal is then recorded in the recording/reproducing system by pit edge recording.

As a result, the recording signal for two waves becomes one wave, but 1/2
The phase information of the previous two waves is recorded in the recording/reproducing system as the timing of the upgoing edge and the downgoing edge, respectively.

During reproduction, an edge detector reproduces the recorded signal at the pit edge. As a result, the recording signal is 1 for each amplifier going edge and downgoing edge.
Restored wave by wave. Since the phase of this restored wave corresponds to the amplifier, it is nothing but the FM modulation signal at the time of recording.

Therefore, by demodulating this signal with an FM demodulator, the original image information can be obtained.

[Effect]

Recording signals such as image information are FM modulated and divided into 2 by a divider.
After reducing the recording signal to 1/2, pit edge recording is performed to convert the recording signal of 2 waves into 1 wave, but the phase information of the 2 waves before 1/2 is used as the timing of the upgoing edge and downgoing edge. Recorded on the recording/playback system. As a result, the bandwidth of the recorded recording signal becomes smaller than the bandwidth of the original image information, etc. Therefore, by using the recording method of the present invention, it is possible to record information in a band wider than the bandwidth of the recording/reproducing system.

During playback, the edge detector doubles the signal recorded in the recording/playback system. As a result, the signal is restored one wave at a time for each amplifier going edge and downgoing edge. By demodulating this reproduced signal with an FM demodulator, signals such as original image information can be obtained.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. Recording signals such as image information are input from recording signal input terminal 1,
FM modulation is performed by an FM modulator 2.

This FM-modulated recording signal is further divided into two by a divider 3, and the signal of two waves is converted into one wave and pit-edge recorded on a recording/reproducing system 4 such as an optical disk. During reproduction, the signal recorded in the recording/reproducing system 4 is doubled by the edge detector 5, then demodulated by the FM demodulator 6, and the reproduced image information is outputted from the output terminal 7.

FIG. 2 shows the respective recording signal waveforms. Figure 2(a)
is a recording signal modulated by the FM modulator 2, which is halved by the divider 3 and pit-edge recorded on a recording/reproducing system 4 such as an optical disk.

FIG. 2(b) shows a pit edge recording signal halved. In this way, the signal for two waves becomes one wave and is recorded in the recording/reproducing system 4, but the phase information of the two waves before being divided into half is obtained by the amplifier going of the recording signal shown in Fig. 2(b). Recorded as edge and downgoing amplifier timing. Thereby, the bandwidth of the recording signal such as image information can be narrowed and recorded in the recording/reproducing system 4. Second
Figure (c) shows a reproduced signal obtained by reproducing the signal recorded in the recording/reproducing system 4, and this reproduced signal is doubled by the edge detector 5. FIG. 2(d) shows the reproduced signal doubled by the edge detector 5. The signal is restored one wave at each upgoing edge and downgoing edge of the reproduced signal shown in FIG. 2(c).

Since the phase of this restored wave corresponds to the edge, it is nothing but an FM modulation signal at the time of recording. Therefore, by demodulating this reproduced signal with the FM demodulator 6, image information at the time of recording can be obtained.

In this way, by using the recording method of this embodiment, it is possible to record information in a band wider than the bandwidth of the recording/reproducing system 4, so it is possible to record image information in a wide band, and to improve the image quality. can.

FIG. 3 shows another embodiment of the invention. In this embodiment, a means for correcting second-order distortion is provided in the recording method shown in the first embodiment.

The configuration of this embodiment will be explained below. A signal such as image information inputted from an input terminal 1 is subjected to FM modulation by an FM modulator 2 and then halved by a Teva and Ida 3. After adding the recording signal divided in half by the second divider 3 and the signal with a predetermined duty ratio generated by the burst wave generator 8 as a burst wave in an adder 9, the recording and reproducing system 4 to be recorded. For example, when recording a burst wave with a duty ratio of 50%, the burst wave separation circuit 1
0 is used to separate the burst wave and input it to the burst wave upgoing edge detector and burst wave downgoing edge detector in the correction signal generator 11, and the phase of the output signal of the burst wave upgoing edge detector and the burst wave Compare the phase of the output signal of the town going edge detector. At this time,
If the phase difference is 180 degrees, it can be considered that there is no second-order distortion. The configuration is such that a phase difference of 180 degrees is set as a zero correction signal and a correction signal proportional to the phase difference is output. On the other hand, the reproduced signal is input to the edge detector 5. When edge detecting this reproduced signal, the second-order distortion is corrected by delaying or advancing either the amplifier coercing energy detect signal or the downgoing edge detect signal in accordance with the phase correction signal. This corrected reproduced signal is pit-edge demodulated to restore it to an FM signal, and this FM signal is further demodulated by an FM demodulator 6 to reproduce an image signal.

By using the second-order distortion correcting means as in this embodiment, it is possible to avoid the influence of second-order distortion that causes jitter errors, and it is also possible to obtain the same effects as in the first embodiment.

〔Effect of the invention〕

Since the present invention is configured as described above, it produces the effects described below.

In a recording and reproducing system such as an optical disk, image information having a wider band than the recording and reproducing system can be recorded, so that image quality can be improved. By using a second-order distortion correction means in the recording and reproducing system, it is possible to avoid the influence of second-order distortion that causes jitter errors, and it is also possible to improve image quality.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a first embodiment of the present invention, FIG. 2 is an explanatory diagram of signal waveforms of the first embodiment, and FIG. 3 is a block diagram of a second embodiment. 2-FM modulator, 3-Divider, 4-Recording/reproduction system, 5-Edge detector, 6-FM demodulator, 8-Burst wave generator, 9-Adder, 10-Burst wave separation circuit, 11-Correction signal generator. Poison 2 figure 0 anti)

Claims (1)

[Claims] 1. As a method for recording and reproducing signals such as image information on a recording/reproducing system such as an optical disk, recording signals such as image information are recorded using FM.
It includes a means for modulating the FM modulated signal and a means for pit-edge modulating the FM modulated signal, records the pit-edge modulated recording signal on the recording/reproducing system, and transmits the pit-edge recorded signal to the pit edge. 1. A method for recording wideband image information, characterized in that it is configured to reproduce by means of edge demodulation and FM demodulation, and is capable of recording image information in a wideband twice as wide as the bandwidth of a recording/reproducing system. 2. The configuration according to claim 1 is provided with a secondary distortion correction means,
A method for recording broadband image information, characterized in that the method is configured to avoid the influence of second-order distortion that causes jitter errors.