JPS6212587B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention records on a disk-shaped recording medium by mixing concentric recording trajectories and spiral recording trajectories,
When a predetermined recording trajectory is searched during playback, it is detected whether the searched recording trajectory is a concentric recording trajectory or a spiral recording trajectory, and the drive system is controlled based on the detection output. This invention relates to a recording and reproducing method that can automatically perform reproduction suitable for each recording trajectory.

Conventionally, for example, a disk-shaped recording medium is formed using a photosensitive material, this recording medium is rotated, and light from a laser is focused on the disk and irradiated with a diameter of 1 μm or less. , Signals are recorded or reproduced on the recording medium at high density as changes in unevenness or shading.

For example, optical video discs are well known among the above-mentioned technologies as a device that only plays back signals recorded in advance at high density.

Further, the above-described recording technique is used in an apparatus for making a master disc of a video disc.

Furthermore, video signals, audio signals, and digital signals are also being considered as recording signals.

In the optical recording or reproducing apparatus described above, signals are generally recorded on a disk so as to constitute a spiral information track. Some devices for recording digital information, etc., form concentric information tracks. Whether information is recorded on the disk using concentric tracks or spiral tracks can be easily selected by defining the manner of relative movement between the disk and the optical head.

When recording and reproducing a signal, the present invention records on concentric tracks depending on the content of the recorded signal.
To provide a method for reproducing signals without confusion from a disc created by recording as a spiral track.

Examples of suitable examples of recording signals in the form of a mixture of concentric tracks and spiral tracks on a single disk as described above include still images and moving images, or still images and audio signals, etc. .

In the following description, a case where still images and moving images are recorded will be described as an example.

FIG. 1 shows an example of an input device for recording signals in the optical recording/reproducing device 50. As shown in FIG.

One method for recording a mixture of still images and moving images on a single disk is to record all of the still images and moving images on a spiral track. In this case, the software to be recorded on the disc must have been edited in advance by an amount equivalent to one disc and recorded on a tape such as a VTR 51. That is, in such an optical recording/reproducing device, the disk and the optical head move at a constant relative speed so that the irradiated light forms a spiral track on the disk, and the recording video signal is supplied in accordance with this movement. There is a need to.

The television camera 5 of the input device shown in FIG.
2, a television tuner 53, etc., to selectively and sequentially record images occurring at arbitrary times as still images, the optical head and disk move relative to each other regardless of the recording signal. Therefore, it becomes impossible to know where on the disk the signal will be recorded, which is unfavorable in terms of disk usage efficiency. Also, when playing back signals from a disk created in this way, still images, videos, and areas with no signals are mixed, and it is necessary to identify these, and when searching for arbitrary still images or videos. Therefore, it becomes extremely impractical.

For the above reasons, in order to record a mix of still images and videos on a single disk and make it easier to play and search, it is recommended to record still images on concentric tracks and videos on spiral tracks. is preferable from the standpoint of disk usage efficiency and the configuration of the optical recording/reproducing device.

By doing the above, when recording a still image, the light from the optical head can draw a circular trajectory on the disk while waiting for the software to record to be input, as shown in Figure 1. Even if the software input means is a video signal from a TV camera or TV radio waves, it is possible to record at any time without sufficiently losing the recording area on the disk.

As described above, the present invention provides an apparatus for recording/reproducing or only reproducing a disk in which a concentric track and a spiral track coexist. is determined based on the track form information signal included in the reproduced search information signal, and concentric track reproduction and spiral track reproduction are automatically performed.

The details of the present invention will be explained below with reference to the drawings.

FIG. 2 shows a part of a configuration example of an optical recording/reproducing apparatus.

In FIG. 2, numeral 1 indicates a disk using the photosensitive material. This disk has disk motor 5
It rotates around the spindle 4 of. This rotation speed is, for example, 1800 rpm in order to record one frame of NTSC video signal per rotation. 2 indicates a turntable, and 3 indicates a disc holder.

6 indicates an optical system unit (optical head). 6
Reference numeral 1 indicates a light source such as a laser, which generates light a. 6
2 indicates a condensing optical system for concentrating the light from the light source 61. Reference numeral 63 indicates a known tracking mirror. 6
Reference numeral 4 denotes an objective lens for focusing the light a to a minute diameter and irradiating the disk 1 with it. This objective lens performs focus control using a known voice coil or the like. b
indicates the reflected light from the disk. A beam splitter 65 separates reflected light b from the optical path of light a and directs it toward a photoelectric converter 66. The photoelectric converter 66 is a high-speed photoelectric converter such as a PIN diode, which detects signals recorded on the disk, and also detects focus error signals and tracking error signals using a known divided PIN diode. Let's do it. Reference numeral 67 indicates a preamplifier of the photoelectric converter 66, and a reproduction signal is outputted to a terminal Q. Reference numeral 7 indicates a laser driving device, and during recording, a signal to be recorded (for example, an FM-modulated video signal) is input to a terminal P. Reference numeral 8 indicates a transfer screw for transferring the optical system unit 6 in either direction of arrows A or B with respect to the disk.

Reference numeral 9 indicates a transfer motor that provides rotational power to the transfer screw, and is composed of a DC motor or the like. Reference numeral 10 indicates a rotation angle detector of the transfer screw 8 using a rotary encoder or the like. This rotation angle detector 10 uses a transfer motor 9 to move concentric tracks on the disk 1.
. . X-2, X-1, X, X+1, . That is, the rotation angle of the transfer screw 8 is detected, and a signal for stopping the transfer motor 8 is generated when the transfer screw 8 has rotated by a certain angle corresponding to one pitch of the track.

11 indicates a transfer motor drive circuit. Reference numeral 12 indicates an operation panel, and this operation panel includes operation switches (for example, a switch for specifying modes such as recording mode and playback mode, and a switch for selecting a recording target of a moving image or a still image), and a switch for controlling the optical system unit 6 as indicated by arrows A and B. A search switch 122 (a numeric keypad for specifying a search number, a switch for specifying a search mode, etc.) 121 is provided. In FIG. 2, if the mode switch of the operation switch 121 is set to recording mode and the moving image/still image switching switch is set to moving image, for example, the transport motor 9
rotates without being controlled by the rotary encoder 10 and continuously feeds the transfer screw 8 at a constant speed. In this way, signals can be recorded spirally on the disk. On the other hand, if the moving image/still image switching switch is set to a still image, the transport motor 9 rotates under the control of the rotary encoder to feed the optical system unit in steps and record signals on concentric tracks. be able to.

Figure 3 shows one of the disks produced by the device shown in Figure 2, on which a mixture of still images and videos are recorded.
Give an example. In Figure 3, area a shows the area where still images were recorded on a disk rotating at 1800 rpm to form concentric tracks, and a ₁ , a ₂ , a ₃ , and a ₄ each represent one frame of still images. shows the concentric tracks where are recorded. On the other hand, area b indicates a spiral track on which a moving image is recorded, and b ₁ , b ₂ , b ₃ , and b ₄ indicate tracks on which signals are recorded.

A fan-shaped area V in FIG. 3 shows where the vertical synchronization signal of the recorded video signal is recorded. In the vertical synchronization signal section of each of these tracks, a search information signal (a number unique to each track) is recorded superimposed on the video signal for each track using a known technique. The search information signal is used as a search address when randomly searching and reproducing an arbitrary track of a recorded video signal.

When recording a signal on the disk shown in FIG. 3, the operator selects the operation switch 12 shown in FIG.
As mentioned above, by pressing the moving image/still image switching switch 1, it is possible to control whether the optical head forms a concentric trajectory or a spiral trajectory with respect to the disk. However, when searching for and playing back a specified track on the disk shown in FIG. 3 by specifying the track number using the numeric keypad of the search switch 122 shown in FIG. Is there a truck?
It is necessary to automatically determine whether a track is recording a still image in concentric circles and to automatically control the transport motor and transport screw shown in FIG. That is, once a track recorded in a spiral shape is captured, the optical head must rotate the transport motor 9 to continuously move the optical system unit 6 in order to draw a spiral trajectory on the disk. .

The present invention will be specifically explained using the drawings from FIG. 4 onwards.

FIG. 4 shows an example of a search information signal decoding circuit and a concentric track/spiral track discrimination circuit used in the present invention. FIG. 5 shows an example of waveforms at each part in FIG. 4. Furthermore, FIG. 6 shows an enlarged view of the search information signal section. The symbols attached to the waveforms in FIGS. 5 and 6 correspond to the symbols attached to the lines in FIG. 4.
In this embodiment, the PE (Phase encoding) method is used as the modulation method for the search information signal, and the search address is BCD converted and recorded with 1 corresponding to high level and 0 corresponding to low level. . Furthermore, in digital modulation systems, it is generally necessary to place cue bits before effective information bits.

In particular, BCD conversion requires 4 bits for one decimal digit. Therefore, the 4-bit permutation (1010) (1011) that cannot occur in BCD conversion
By using any one of (1100), (1101), (1110, and (1111)) as the cue bit, it is possible to distinguish between the search address and the cue bit. In the embodiment of the present invention, this cue bit is recorded differently depending on whether the track form is concentric or spiral, and during playback, the cue bit is read and automatically recorded. Optical system unit 6
control the transfer of

First, the operation shown in FIG. 4 will be explained with reference to the waveform diagram shown in FIG.

The output of the preamplifier 67 shown in FIG. 2 is input to the terminal Q. 41 indicates an FM demodulator for demodulating the output of the preamplifier 67 into a video signal, and line a
A video signal is output. 42 is a synchronization signal clamp circuit that erases the synchronization signal contained in the video signal and outputs the signal excluding the synchronization signal to line b. 43 is a synchronization signal separation circuit which separates a vertical synchronization signal and a horizontal synchronization signal from the demodulated video signal and outputs them to line c. 44 is an address extraction pulse generation circuit. Generally, the search information signal is inserted into a blanking interval after the vertical synchronization signal. Therefore, this address extraction pulse d generates a pulse for extracting the horizontal synchronization signal section in which the subsequent search information signal is present, with the vertical synchronization signal as a reference. 45 is a search information signal extraction gate circuit;
From the reproduced video signal, only the address signal is output to line e. A self-clock generator 46 generates a self-clock from the address signal e and outputs it to the line f. 47 is a serial/parallel conversion shift register, which reads the address signal on line e with the self-clock output on line f as shown in Figure 6 and outputs it to B _O , and the previous B _O output is sent to _B1 ; Previous B ₁ output is B ₂
1 bit at a time to the right. 4
Reference numerals 8 and 49 indicate inverting circuits, and when the input is at a high level, the output is at a low level, and when the input is at a low level, the output is at a high level. 50, 51 is
In a NAND circuit, the output is low level only when all four inputs are high level, and high level otherwise. 52 is a set/reset flip-flop circuit; when the S input goes low, the T output goes high; when the R input goes low, the T output goes low.

When the cue bits are 1, 1, 1, 1 in order,
As can be seen in FIG. 6, _R1 goes low and, from the previous discussion, the T output goes high.
Similarly, when the cue bits are 1, 0, 1, 0 in this order, _R2 becomes low level and the T output becomes low level.

Therefore, when recording on a spiral track, the cue bits of the search information signal are set to 1, 1, 1, 1, and when recording on a concentric track, the cue bits are set to 1, 0, 1, 0. During playback, the T output changes depending on the track format.
When the output is at a high level (that is, a spiral track), the transfer motor 9 shown in FIG. 2 is operated, and the T
When the output is at a low level (ie, concentric track), the transfer motor 9 may be stopped.

As is clear from the above explanation, by controlling the rotation of the transfer motor 9 shown in FIG. 2 based on the T output of the set-reset flip-flop circuit 52 shown in FIG. On a disk with a mixture of tracks and spiral tracks, check whether the tracks captured by the optical system unit are concentric circles or not.
By automatically determining whether the track is a spiral track and controlling the transfer motor, it is possible to realize a method of regenerating without confusion even when the track form changes (concentric or spiral).

In the manner described above, a disc containing a mixture of moving images and still images, a disc containing a mixture of still images and audio, etc. can be easily reproduced.

In the above explanation, in order to include the track type information signal in the search information signal, a method was used in which the cue bit of PE modulation was changed depending on the track type. Odd parity for concentric tracks,
A conceivable method is to record the track as even parity when it is a spiral track, and then determine whether it is odd parity or even parity during playback to control the transport motor. In the case of this method, Binary conversion may be used, and the number of required bits can be reduced compared to BCD conversion.

According to the present invention, by including the track type signal in the cueing signal necessary for demodulating the search address signal, it is possible to save on the increase in recording bits required to record track type information.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of an input device for an optical recording/reproducing device, FIG. 2 is a block diagram showing an example of the configuration of an optical recording/reproducing device, and FIG. 3 is a combination of concentric tracks and spiral tracks. A diagram showing a disk to be used,
FIG. 4 is a diagram showing an example of the configuration of a circuit for determining whether a concentric track or a spiral track is used, which is a main part of the recording/reproducing apparatus according to the present invention. FIG. 5 is a waveform diagram of each part of FIG. 4. FIG. 5 shows an enlarged view of the search information signal extraction section of FIG. 5. FIG. DESCRIPTION OF SYMBOLS 1...Disc-shaped recording medium (disk), 6...Optical system unit, 8...Transfer screw, 9...Transfer motor, 10
...D-Tally encoder, 11...Transfer motor drive circuit.

Claims (1)

[Claims] 1 A recording and reproducing method in which concentric tracks and spiral tracks are recorded on the same disc-shaped recording medium, in which a track form information signal corresponding to the track form is inserted into each information track at the time of recording, and at the time of playback, Extracting the track form information signal from the playback signal played back by the playback pickup means, and driving a transport means for relatively moving the disc-shaped recording medium and the playback pickup means in accordance with the playback track form information signal. 1. A recording and reproducing method characterized in that the track type information signal is also used as a cue signal for a search address signal of each information track.