JPH0411301A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To allow dealing with an increase in the number of heads and an increase in frequency bands by providing a opto-electric converter which is mounted on a rotary cylinder and is electrically coupled to magnetic heads, another opto-electric converter which is optically coupled to this converter and a signal processor. CONSTITUTION:The video signals to be recorded are inputted via a signal input terminal to the signal processor 2 and are sent to the opto-electric converter 3 after the signals are subjected to analog to digital conversion, time base conversion and high- efficiency encoding, etc. The inputted electric signals are converted to light signals in this opto-electric converter 3 and the light signals are transmitted via an optical communication path 9 to another opto-electric converter 4. The received light signals are decoded to the electric signal in the opto-electric converter 4. The signals are successively recorded on a magnetic tape 7 via the magnetic heads 5, 6. The information recorded on the magnetic tape 7 is read by the magnetic heads 5, 6 and is converted to the light signals by the opto-electric converter 4 at the time of reproducing. The received light signals are decoded to the electric signals in the opto-electric converter 3. These signals are applied to the signal processor 2. The increase in the number of the heads and the increase in the frequency bands are possible in this way.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a magnetic recording/reproducing device.

2. Description of the Related Art Various recording and reproducing apparatuses using magnetic tape as a recording medium have been developed and put into practical use. For example, a video tape recorder (hereinafter referred to as "VTR") is a typical example, and in recent years, the popularity of home VTRs has increased significantly, and their performance has improved significantly. Recently, many functions have been added to the camera, making it small and lightweight and capable of recording for long periods of time.

Therefore, the current analog VTR, which was already mentioned as a conventional example,
(hereinafter referred to as "AVTR") will be described with reference to FIG. In the figure, 26 is a video signal input terminal, 27 is a signal processor, 28 and 29 are rotary transformers, and 30
31 is a magnetic head, 32 is a magnetic tape, 33 is a rotating cylinder, and 34 is a video signal input terminal.

The video signal to be recorded is input to the signal processor 27 via the signal input terminal 26, subjected to clamping, emphasis, FM modulation, low frequency conversion of the carrier color signal, etc. The data is recorded on the magnetic tape 32 via the magnetic tape 32. The magnetic heads 30 and 31 are mounted on a rotating cylinder 33, and the magnetic heads 30 and 31 are mounted on a rotating cylinder 33.
2, magnetic heads 30 and 31 record while rotating. Further, as for the rotary transformers 28 and 29, the primary side thereof is fixed to a rotating cylinder, and the secondary side thereof is fixed to a stationary cylinder.

On the other hand, during reproduction, information recorded on the magnetic tape 32 is read by the magnetic heads 30 and 31 and applied to the signal processor 27 via the rotary transformers 28 and 29. The signal processor 27 performs clamping, de-emphasis, FM demodulation, and inverse conversion of the low frequency conversion carrier color signal. In this manner, the reproduced signal is output from the video signal output terminal 34.

Next, an outline of the reproduction characteristics in the conventional example shown in FIG. 4 will be explained with reference to FIG. 5. In the figure, the horizontal axis is the frequency, the vertical axis is the gain, and the curve 35 is the reproduction frequency characteristic. During playback, the magnetic force of the magnetic tape 32 is received by the magnetic heads 30 and 31, converted into an electric signal by the coils wound around the magnetic discs 30 and 31, and sent to the signal processor 2 via the rotary transformers 28 and 29.
Supply to 7.

However, the inductance components of the magnetic heads 30 and 31, the rotary transformers 28 and 29, and the signal processor 27
The reproduction frequency characteristic becomes like the curve 37 due to the input capacitance of the input capacitor and the stray capacitance of each part. As shown by the curve 37, the transmission band is limited by the low frequency portion and the high frequency portion, and the gain increases in the high frequency portion within the transmission band.

In the conventional system, not only such limitations on the transmission frequency band but also inter-channel crosstalk in the rotary transformer and multichannelization are major issues.

In recent years, the demand for higher image quality in video equipment has been increasing, and the rapid progress in semiconductor technology has led to the development of digital recording VTRs (hereinafter referred to as ``DVTRs''). Research has been carried out, but while DVTR can achieve high image quality by digitizing it, it requires a huge amount of data.

In fact, the recording rate of devices researched and developed for broadcasting exceeds at least 100 Mbps, and for high-definition devices exceeds I Gbps.

On the other hand, for DVTRs aimed at home use, methods of reducing the recording rate by introducing high-efficiency encoding technology for image quality are being actively researched, but even in this case, the frequency band of the signal recorded and played back on magnetic tape is It is considerably more expensive than an analog VTR. As a result, compared to the conventional AVTR shown in Fig. 4, the rotational speed of the rotating cylinder is increased, the number of magnetic heads mounted on the rotating cylinder is increased, and the frequency of signals recorded and reproduced via each magnetic head is increased. Forced to increase bandwidth.

Such an increase in the number of heads and frequency band causes great difficulty in signal transmission between a part of the rotating cylinder and the signal processing section in the deck.

Means for Solving the Problems The present invention provides a magnetic head fixed on a rotating cylinder, and an optical/electrical sensor mounted on the rotating cylinder that electrically couples with the magnetic head and converts electrical signals and optical signals. a converter, another optical-to-electrical converter that is pre-coupled with this optical-to-electrical converter to convert an electrical signal to an optical signal, and another optical-to-electrical converter that is electrically coupled to this other optical-to-electrical converter to convert a predetermined This is a magnetic recording and reproducing device characterized by comprising a signal processor that performs processing.

By doing this, it becomes possible to deal with the above-mentioned problems, namely an increase in the number of heads and an increase in the frequency band, and also to solve the great difficulty caused by signal transmission between a part of the rotating cylinder and the signal processing section in the deck. becomes possible.

Example Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing one embodiment of the present invention. In the figure, 1 is a video signal input terminal, 2 is a signal processor, 3 and 4 are optical/electrical converters, 5 and 6 are magnetic heads, 7 is a magnetic tape, 8 is a rotating cylinder 9 is an optical communication path , 10 are video signal output terminals.

The video signal to be recorded is input to the signal processor 2 via the signal input terminal 1, and is subjected to analog-to-digital conversion, time axis conversion, high efficiency encoding, error correction encoding, formatting,
The signal is subjected to modulation and the like and sent to the optical/electrical converter 3. This optical-to-electrical converter 3 converts the input electrical signal into an optical signal and transmits it to the other optical-to-electrical converter 4 via an optical communication path 9. The optical-to-electrical converter 4 restores the received optical signal to an electrical signal and records it on the magnetic tape 7 via the magnetic heads 5 and 6. The magnetic heads 5 and 6 are mounted on a rotating cylinder 8.

On the other hand, during reproduction, information recorded on the magnetic tape 7 is read by the magnetic heads 5 and 6 and applied to the optical/electrical converter 4. This optical/electrical converter 4 amplifies the electrical signals detected by the magnetic heads 5 and 6, converts them into optical signals, and converts them into optical communication channels 9.
The signal is transmitted to the other optical-to-electrical converter 3 via. light·
The electric converter 3 restores the received optical signal to an electric signal and applies it to the signal processor 2. The signal processor 2 performs demodulation, de-formatting, error correction decoding, high-efficiency coding inverse conversion, time axis inverse conversion, digital-to-analog conversion, and the like. In this way, the playback signal is transferred to the video signal output terminal 10.
is output from.

Next, another embodiment of the present invention will be described with reference to FIG. In the figure, 11 is an input terminal, 12, 14, 20, and 22 are optical/electrical converters, 15 is a recording amplifier (indicated as "R/A" in Figure 2), and 16 is a switch (Figure 2). See you”
17 and 18 are magnetic heads, 19 is a head amplifier (indicated as "H/A" in Fig. 2), 13 and 21 are optical communication channels, 23 is an output terminal, and 24 is a rotating cylinder. .The output of the signal processor 2 in FIG. 1 is applied to the input terminal 11 in FIG. 2, and the output of the output terminal 23 in FIG. 2 is applied to the signal processor 2 in FIG. The signal is sent to the optical-to-electrical converter 12 via the optical communication path 13.The optical-to-electrical converter 12 converts the input electrical signal into an optical signal and transmits it to the other optical-to-electrical converter 14 via the optical communication path 13. The optical/electrical converter 14 restores the received optical signal to an electrical signal, and sends a recording current to the magnetic heads 17 and 18 via the recording amplifier 15 and switch 16. Of course, during recording, the switch 16 is Closed on the recording amplifier side.

On the other hand, during reproduction, information recorded on the magnetic tape 7 is read by the magnetic disks 17 and 18 and supplied to the head amplifier 19 via the switch 16. head amp 19
After the signal is amplified to a predetermined level, it is added to the optical-to-electrical converter 20. This optical-to-electrical converter 20 converts an electrical signal into an optical signal and transmits it to the other optical-to-electrical converter 22 via an optical communication path 21. The optical/electrical converter 22 restores the received optical signal to an electrical signal and applies it to the signal processor 2 shown in FIG. 1 via an output terminal 23. Of course,
During playback, the switch 16 is closed to the head amplifier 19 side.

In this embodiment, optical communication channels are installed independently for recording and reproduction, making it possible to transmit digital signals during recording and analog signals during reproduction.

Next, another embodiment of the present invention will be described with reference to FIG. In the figure, 11 is an input terminal, 12, 14.2
0 and 22 are optical/electrical converters, 15 is a recording amplifier (third
16 is a switch (indicated as "SW" in FIG. 3), 17 and 18 are magnetic heads, 19
is the head amplifier (denoted as "H/A" in Figure 3), 25
13 and 21 are optical communication paths, 22 is an output terminal, and 24 is a rotating cylinder.

11-24 in FIG. 3 correspond to 11-24 in FIG. The output of the signal processor 2 in Fig. 1 is the input terminal 1 in Fig. 3.
1, the output of the output terminal 23 in FIG. 3 is applied to the signal processor 2 in FIG. During recording, the signal is sent to the optical/electrical converter 12 via the input terminal 11. This optical/electrical converter 12
Then, the input electric signal is converted into an optical signal and the optical communication path 13
The signal is transmitted to the other optical-to-electrical converter 14 via the . The optical/electrical converter 14 restores the received optical signal to an electrical signal, and sends a recording current to the magnetic heads 17 and 18 via a recording amplifier 15 and a switch 16. Of course, during recording, the switch 16 is closed to the recording amplifier 15 side.

On the other hand, during reproduction, information recorded on the magnetic tape 7 is read by the magnetic heads 17 and 18 and supplied to the head amplifier 19 via the switch 16. head amp 19
After amplifying the signal to a predetermined level, the signal is converted into a digital signal by a digitizer 25 and applied to an optical/electrical converter 20. The digitizer 25 is composed of an analog-to-digital converter that converts the output of the head amplifier 19 into a digital value, or an equalizer or a detector. The optical-to-electrical converter 20 converts the electrical signal into an optical signal and transmits it to the other optical-to-electrical converter 22 via the optical communication path 21. The optical-to-electrical converter 22 restores the received optical signal to an electrical signal and sends it to the output terminal 23.
The signal is applied to the signal processor 2 in FIG. Of course, during playback, the switch 16 is set to the head amplifier 19.
Closed on the side.

In this embodiment, optical communication channels are installed independently for recording and reproduction, making it possible to transmit digital signals during both recording and reproduction.

Incidentally, the optical transmission lines 9, 13 and 21 generally have a wideband transmission capacity, and have little transmission distortion within the transmission band.Furthermore, inter-channel crosstalk is low, and multiplexing is easy.

In the embodiment of the present invention shown in FIGS. 1 to 3, the installation locations of the optical communication channels 9, 13 and 21 are not mentioned, but it is possible to introduce and extract light along the central axis of the rotating cylinder 8, etc. is possible.

In addition, although the number of heads is illustrated assuming that two heads are mounted to simplify the explanation, it is not limited to two, and rather the present invention becomes more effective as the number of heads increases. The effect is large. (The same applies to the number of recording amplifiers and the number of head amplifiers, and the number is not limited to one.)Furthermore, in FIG. 1, the recording amplifier and head amplifier are not shown to simplify the explanation. However, in reality, a circuit is required between the optical/electrical converter 4 and the magnetic heads 5 and 6 to execute the operations of the recording amplifier and the head amplifier.

Effects of the Invention As is clear from the above explanation, the present invention enables an increase in the number of heads and an increase in the frequency band, and achieves high performance and high quality signal transmission between a part of the rotating cylinder and the signal processing unit in the deck. It is what makes it possible. As a result, it is particularly effective in devices such as DVTRs that are forced to perform multi-channel, high-bandwidth transmission.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the invention, FIG. 2 is a block diagram showing another embodiment of the invention, FIG. 3 is a block diagram showing still another embodiment of the invention, and FIG. 4 is a block diagram showing another embodiment of the invention. The figure is a schematic diagram showing a conventional system, and FIG. 5 is a characteristic diagram showing transmission frequency characteristics in the conventional system of FIG. 1...Signal processor, 3.12.14.20.2
2...Photoelectric converter, 5. 6.17.18・
...Magnetic head, 7...Magnetic tape, 8
...Rotating cylinder, 9゜13, 21...
...Optical communication path, 15... Recording amplifier, 16...
...Switch, 19...Head amplifier, 2
5... Digitizer.

Claims (4)

[Claims] (1) A magnetic head fixed on a rotating cylinder, an optical/electrical converter mounted on the rotating cylinder and electrically coupled to the magnetic head to convert an electrical signal to an optical signal, and the optical/electrical converter Another optical-to-electrical converter that is optically coupled to the converter and converts an electrical signal to an optical signal, and a signal processor that is electrically coupled to the other optical-to-electrical converter and performs predetermined processing. A magnetic recording/reproducing device comprising: (2) a magnetic head fixed on a rotating cylinder; two sets of optical-to-electrical converters mounted on the rotating cylinder and electrically coupled to the magnetic head to convert electrical signals and optical signals; another two sets of optical/electrical converters that are optically coupled with the two sets of optical/electrical converters to convert electrical signals and optical signals; The two sets of optical-to-electrical converters and the other two sets of optical-to-electrical converters include one set for recording and the other set for reproduction. A magnetic recording/reproducing device characterized by using each of the following. (3) a magnetic head fixed on a rotating cylinder; two sets of optical-to-electrical converters mounted on the rotating cylinder and electrically coupled to the magnetic head to convert electrical signals and optical signals; another two sets of optical/electrical converters that are optically coupled with the two sets of optical/electrical converters to convert electrical signals and optical signals; The two sets of optical-to-electrical converters and the other two sets of optical-to-electrical converters include one set for recording and the other set for reproduction. A magnetic recording/reproducing apparatus characterized in that one set is optically transmitted in the form of a digital signal and the remaining one set is optically transmitted in the form of an analog signal. (4) A magnetic head fixed on the rotating cylinder, an optical/electrical converter mounted on the rotating cylinder that converts electrical signals and optical signals, and an optical/electrical converter mounted on the rotating cylinder that converts analog signals into digital signals. a digitizer for converting into a state, and another optical-to-electrical converter for optically coupling with the optical-to-electrical converter to convert an electrical signal and an optical signal;
A signal processor is provided that electrically couples with the other optical/electrical converter and performs predetermined processing, and the magnetic head and the optical/electrical converter are directly electrically coupled during recording and during reproduction. A magnetic recording/reproducing apparatus characterized in that the magnetic head and the optical/electrical converter are electrically coupled via the digitizer.