JP2682462B2 - Optical disk drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc for recording / reproducing image information using a laser beam, and more particularly to a video-on-demand system for reproducing an image from the same video disc at an arbitrary time interval according to a request. The present invention relates to a compatible optical disk device.

[0002]

2. Description of the Related Art An optical disk recording system using a laser beam is capable of performing large-capacity recording and non-contact high-speed access. Optical discs are classified into a read-only type known as a compact disc and a laser disc, a write-once type that can be recorded by the user himself, and a rewritable type that can be repeatedly recorded and erased by the user. The write-once / rewritable optical disk is used as an external memory of a computer or as a document / image file.

Conventionally, a reproduction-only video disk device is usually equipped with one reproduction optical head.

FIG. 4 is a block diagram of a disk reproducing apparatus having a conventional reproducing optical head, FIG. 4 (a) is a plan view thereof, and FIG. 4 (b) is a front view thereof.

Conventionally, in a read-only video disk apparatus, as shown in FIG. 4, a single disk for playback is usually connected to a slider 5 which is an optical head position control means for a video disk 11 rotated by a motor. The optical head 4 is mounted.

[0006]

In the above-mentioned conventional reproduction-only video disk apparatus, one reproduction apparatus is used to output the same video information to a plurality of output requests.
When attempting to play back with a time lag, either the video being played back must be interrupted, or the video must be played back from the beginning after the video playback has ended to the end.

In recent years, a video-on-demand system has been developed which delivers the same video information to a plurality of viewers through CATV and the like with a time lag. In the case of application, there are drawbacks that it is necessary to prepare a plurality of disc reproducing devices and a plurality of same video discs, which requires equipment cost, and further requires the same plural pieces of software.

For example, as shown in FIG. 5, a plurality of (in this case, two) optical head position control means sliders 5 for the video disk 11 are provided in one disk reproducing device.
"Video disc reproducing apparatus and image response system" for the purpose of mounting a plurality (two in this case) of reproduction-only optical heads connected to the same and supplying the same video information to a plurality of distribution requests. Is known, and as a known example thereof, there is JP-A-2-287989.

However, this system has a drawback in that the image information that can be transmitted is limited to the video disc to be used, and the image information edited independently cannot be transmitted in the form of video on demand.

FIG. 5 is a diagram showing the structure of a conventional video disc reproducing apparatus.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to respond to a video output request from a viewer, which has a simple structure and enables transmission from a video disc and transmission of video information edited independently. An object of the present invention is to provide an optical disk device capable of constructing a system, that is, a video-on-demand system that delivers the same video information with a time lag.

Therefore, the optical disk device of the present invention is a video-on-demand compatible optical disk device for reproducing video information from the same video disk at arbitrary time intervals according to a request, and at least one video disk reproducing mechanism. And a rewritable optical disc mechanism mounted on the video disc reproducing mechanism and the rewritable optical disc mechanism, the rewritable optical disc mechanism and at least one recording for recording and erasing video information on the rewritable optical disc. An erasing optical head, a plurality of reproduction-only optical heads for reproducing video information of a rewritable optical disc, and a plurality of optical head position control means for controlling the position of each reproduction-only optical head,
At least one recording / erasing laser driving circuit for driving recording / erasing of image information by the recording / erasing optical head, a laser modulation circuit for modulating a laser to the recording / erasing laser driving circuit, and reproduction from each reproduction-only optical head A plurality of reproduction signal amplifiers for amplifying signals, and a laser modulation circuit input for inputting the video signal from the video disk reproduction mechanism and the video signal from the reproduction signal amplifier, selecting and amplifying the video signal and outputting it to the laser modulation circuit And a switch portion.

The optical disk device of the present invention is a video-on-demand compatible optical disk device for reproducing video information from the same video disk at arbitrary time intervals in response to a request, and is a reproduction-only information recording portion and rewritable information recording. A partial ROM type optical disc having a portion and a rewritable optical disc mechanism for recording / erasing / reproducing image information on / from the partial ROM type optical disc. At least one recording / erasing optical head for performing, a plurality of reproduction-only optical heads for reproducing video information of the partial ROM type optical disk, and a plurality of optical head position control means for controlling the position of each reproduction-only optical head, At least one recording / erasing for driving recording / erasing of image information by the recording / erasing optical head A laser drive circuit, a laser modulation circuit for modulating the laser to the recording / erasing laser drive circuit, a plurality of reproduction signal amplifiers for amplifying the reproduction signal from each reproduction-only optical head, and a video signal from the reproduction signal amplifier And a laser modulation circuit input switch section for selecting and amplifying an inputted video signal and outputting at least one video signal to the laser modulation circuit.

In the rewriting portion of the optical disk device of the present invention,
Media such as magneto-optical and phase change are used.

[0015]

Next, embodiments of the present invention will be described with reference to the drawings.

The first optical disk device according to the present invention comprises a video disk reproducing mechanism and a rewritable optical disk mechanism having a plurality of reproduction-only optical heads.

The rewritable optical disk mechanism is equipped with, for example, 8 or 16 read-only optical heads and recording optical heads. Only one recording optical head is required. Since each head is arranged radially from the center of the disk and each head is mounted on an independent slider, it is possible to access any position in the radial direction. Once, the video signal from the video disk reproducing mechanism equipped with the video disk is recorded in the rewritable optical disk mechanism, and each reproducing head is used to continuously reproduce the video information at a set time interval. For example, it is possible to continuously reproduce the same video information at 5-minute intervals. Thus, since the same video information is output from the disk device according to the present invention at regular time intervals, this single device can meet the requests from a plurality of viewers and video on demand.

FIG. 1 is a diagram showing the configuration of an embodiment of the first optical disk device according to the present invention.

This is an example of using a rewritable optical disk mechanism equipped with eight optical heads. Playback video signal 10 from video disk playback mechanism 1 equipped with video disk 11
0 is input to the rewritable optical disc mechanism 2. The rewritable optical disk mechanism 2 includes a plurality of read-only optical heads 4 independent of the recording / erasing optical head 3, sliders 5 as a plurality of optical head position control means, and a plurality of reproduction signal amplifiers 6. A laser modulation circuit input switch section 7, a recording / erasing laser drive circuit 8 and a laser modulation circuit 9 are provided. The read-only optical head 4 and the recording / erasing optical head 3 are mounted on a slider 5 which is an optical head position control means, and the read signal output of each read-only optical head 4 is connected to a read signal amplifier 6. The video signal 100 from the video disk reproduction mechanism and the output of the reproduction signal amplifier 6 are connected to the laser modulation circuit 9 of the rewritable optical disk mechanism 2 via the laser modulation circuit input switch section 7. Further, the output of the laser modulation circuit 9 is connected to the recording / erasing laser drive circuit 8 and supplies a recording signal to the recording / erasing optical head 3.

The recording / erasing optical head 3 and the read-only optical head 4 are arranged radially from the center of the rewritable optical disk 10. Since each optical head is mounted on an independent slider 5, each optical head is independent. It is possible to access any position in the radial direction of the optical disc. As a method of using each reproduction-only optical head, there is a method of continuously reproducing video information at set time intervals. For example, it is possible to continuously reproduce the same video information at 5-minute intervals.

The optical disc used in the optical disc apparatus according to this embodiment can be a rewritable optical disc such as a magneto-optical disc or a phase change optical disc. For example, as a magneto-optical disk, a rare earth transition metal alloy Tb is used.
Fe, TbFeCo, GdTbFeCo, DyFeC
A disc having a recording film of o, NdDyFeCo, or the like is used. In this case, the read-only optical head must be capable of detecting the read signal of the magneto-optical disk.

A phase change optical disk can also be used. For example, GeTe, which is a chalcogenide material,
GeSbTe, InSbTe, PdGeSbTe, Ag
A phase change optical disc having a recording film such as InSbTe is used. In this case, since the reproduction signal can be detected as a change in the amount of reflected light, the reproduction-only optical head used in a normal reproduction-only compact disk or laser disk is used as it is for the reproduction-only optical head of the rewritable optical disk mechanism of the present invention. Can be used as

Next, a second optical disk device according to the present invention will be described with reference to the drawings.

FIG. 2 is a diagram showing the configuration of an embodiment of the second optical disk device according to the present invention.

In an example in which a rewritable optical disk mechanism equipped with eight optical heads and a partial ROM disk 12 having a read-only information recording part (ROM) in a part and another part being a rewritable information recording part are used. is there. A video signal is recorded in advance in the ROM portion. The rewritable optical disk mechanism includes a recording / erasing optical head 3, a plurality of independent read-only optical heads 4, sliders 5 as a plurality of optical head position control means, and a plurality of reproduction signal amplifiers 6.
1, a laser modulation circuit input switch section 7, a recording / erasing laser drive circuit 8, and a laser modulation circuit 9.
A read-only optical head 4 and a recording / erasing optical head 3 are mounted on a slider 5 which is an optical head position control means, and the read signal output of each read-only optical head 4 is a read signal amplifier 6 respectively.
Connected to. Reproduced video signal 10 from the ROM area or rewritable information recording portion obtained from the reproduction signal amplifier 6.
1 is connected to a laser modulation circuit 9 via a laser modulation circuit input switch section 7. Further, the output of the laser modulation circuit 9 is connected to the recording / erasing laser drive circuit 8 and supplies a recording signal to the recording / erasing optical head 3.

The recording / erasing optical head 3 and the reproduction-only optical head 4 are arranged radially from the center of the rewritable optical disk 10. Since each optical head is mounted on an independent slider 5, each optical head is independent. It is possible to access any position in the radial direction of the optical disc. As a method of using each reproduction-only optical head, there is a method of continuously reproducing video information at set time intervals. For example, it is possible to continuously reproduce the same video information at 5-minute intervals.

The optical disk used in the embodiment of FIG.
FIG. 3 is a partial ROM disk, and FIG. 3 is a diagram showing a configuration of an embodiment of a partial ROM optical disk according to the present invention.

As shown in FIG. 3, a reproduction-only information recording portion 121 is partly provided and another portion is a rewritable information recording portion 122. In the rewritable information recording portion 122,
A magneto-optical medium or a phase change medium is deposited. Similar to a normal read-only disc, the read-only information recording portion 121 is provided with concave and convex pits in advance. Magneto-optical media include rare earth transition metal alloys TbFe, T
bFeCo, GdTbFeCo, DyFeCo, NdD
yFeCo or the like is used as the recording film. in this case,
The read-only optical head must have a configuration capable of detecting a reproduction signal of the magneto-optical disk. Also, the rewritable information recording portion 1
It is also possible to use a phase change medium for 22. For example, chalcogenide materials such as GeTe, GeSbTe, In
SbTe, PdGeSbTe, AgInSbTe, etc. are used as the recording film. In this case, since the reproduction signal can be detected as a change in the amount of reflected light, the reproduction-only optical head used in the normal reproduction-only compact disk or laser disk can be used as it is as the reproduction-only optical head.

As described above, since the same video information is output from the optical disk device according to the present invention at regular time intervals, this single device can meet the requests from a plurality of viewers and video on demand. However, since the optical disk device according to the present invention uses the rewritable optical disk or the partial ROM disk in addition to these functions, it is possible to reedit the original video signal independently.
For example, it is possible to pick up a video signal sent from the video disc reproducing mechanism, reconstruct it into new video data, and program it. Further, as shown in FIG. 1 or 2, it is also possible to provide an external video signal input terminal 77 in the laser modulation circuit input switch section 7 of the rewritable optical disk mechanism and input external video information from there. By inputting independently recorded video information, such as video recorded by a video camera, from this terminal, it can be edited as a program by this device.

Further, although the reproducing apparatus equipped with eight optical heads has been described here, the number of the optical heads is not limited to this embodiment, and the number of the optical heads is limited as long as the physical space permits. It is possible to increase For optical disk devices with more optical heads,
The number of viewers who can simultaneously use the same disc will increase.

[0031]

As described above, the optical disc apparatus of the present invention has a simple structure and serves as a system that responds to video output requests from a plurality of viewers, and delivers the same video information with a time difference. It is possible to realize an optical disk device most suitable for an on-demand system, and it is possible to edit original video information by using a rewritable optical disk or a partial ROM disk.

[Brief description of the drawings]

FIG. 1A is a diagram showing a configuration of an embodiment of a first optical disk device according to the present invention. FIG. 1B is a front view of the rewritable optical disc mechanism shown in FIG.

FIG. 2A is a diagram showing a configuration of an embodiment of a second optical disk device according to the present invention. FIG. 2B is a front view of the rewritable optical disc mechanism shown in FIG.

FIG. 3 is a diagram showing a configuration of an embodiment of a partial ROM optical disk according to the present invention.

FIG. 4A is a plan view showing a configuration of a disk reproducing apparatus including one reproducing optical head of a conventional example.
FIG. 4 (b) is a front view of FIG. 4 (a).

FIG. 5A is a plan view showing a configuration of a conventional video disc reproducing apparatus. FIG. 5 (b) is a front view of FIG. 5 (a).

[Explanation of symbols]

 1 Video Disc Reproducing Mechanism 2 Rewritable Optical Disc Mechanism 3 Recording / Erasing Optical Head 4 Reproducing Dedicated Optical Head 5 Optical Head Position Control Means (Slider) 6 Reproducing Signal Amplifier 7 Laser Modulation Circuit Input Switch Section 8 Recording / Erasing Laser Driving Circuit 9 Laser Modulation circuit 10 Rewritable optical disc 11 Video disc 12 Partial ROM disc 77 External video signal input terminal 100, 101 Reproduced video signal 121 Reproduction-only information recording portion 122 Rewritable information recording portion

Claims (7)

(57) [Claims] 1. A video-on-demand compatible optical disc apparatus for reproducing video information from the same video disc at an arbitrary time interval in response to a request, wherein at least one video disc reproducing mechanism and the video disc reproducing mechanism. And a rewritable optical disc mechanism, wherein the rewritable optical disc mechanism and the at least one recording / erasing optical head for recording / erasing video information on the rewritable optical disc. A plurality of reproduction-only optical heads for reproducing the image information of the rewritable optical disc, a plurality of optical head position control means for controlling the position of each reproduction-only optical head, and an image by the recording / erasing optical head. At least one recording / erasing laser driving circuit for driving the recording / erasing of information, and to the recording / erasing laser driving circuit A laser modulation circuit for modulating a laser, a plurality of reproduction signal amplifiers for amplifying reproduction signals from the reproduction-only optical heads, a video signal from the video disk reproduction mechanism and a video signal from the reproduction signal amplifier are input. And a laser modulation circuit input switch section for selecting and amplifying the video signal and outputting it to the laser modulation circuit. 2. A partial ROM having a read-only information recording portion and a rewritable information recording portion in a video-on-demand optical disc device for reproducing video information from the same video disc at arbitrary time intervals according to a request. -Type optical disk and the partial ROM
At least one recording / erasing optical head for recording / erasing image information on / from the partial ROM type optical disc, the rewritable optical disc mechanism performing recording / erasing / reproducing of image information on / from the partial optical disc. A plurality of reproduction-only optical heads for reproducing video information of the partial ROM type optical disk, a plurality of optical head position control means for controlling the position of each reproduction-only optical head, and the recording / erasing optical head. At least one recording / erasing laser driving circuit for driving recording / erasing of image information, a laser modulation circuit for modulating a laser to the recording / erasing laser driving circuit, and a reproduction signal from each reproduction-only optical head is amplified. A plurality of reproduction signal amplifiers and video signals from the reproduction signal amplifiers are input, and the video signals are selected and amplified at least. An optical disk device comprising: a laser modulation circuit input switch section for outputting one video signal to the laser modulation circuit. 3. The optical disk device according to claim 1, wherein the rewritable optical disk is a magneto-optical disk. 4. The optical disk device according to claim 1, wherein the rewritable optical disk is a phase change optical disk. 5. The optical disc apparatus according to claim 2, wherein the rewritable information recording portion of the partial ROM type optical disc is a magneto-optical recording medium. 6. The optical disc apparatus according to claim 2, wherein the rewritable information recording portion of the partial ROM type optical disc is a phase change optical recording medium. 7. The external video signal input terminal is provided in the laser modulation circuit input switch section.
Alternatively, the optical disk device according to claim 2.