JPS5922251A - Recording device - Google Patents

Abstract

PURPOSE:To record sufficiently and stably a video signal up to a high frequency band and to prolong the life of a recording stylus, by providing the recording stylus with a current limitation circuit and applying high signal voltage to the recording stylus. CONSTITUTION:When video signal voltage Es to be recorded is applied to a recording stylus 6, the signal voltage is applied to the point part of the recording stylus 6 through a capacitor 10. Since the electrostatic capacity between the surfaces of the recording stylus 6 and recording medium 5 is an extremely low value <=10<-2>pF, sufficiently high recording signal voltage is applied to the recording medium 5 through the point part of the recording stylus 6. In addition, limitation of recording current I by >=1M high resistance 12 prevents the recording stylus 6 from flow of high current. Therefore, even if high signal voltage Es is applied, the current I is increased slightly as shown in the characteristic curve B, so that a little defect on the surface of the recording medium does not cause the damage of the recording stylus 6. Consequently, the video signal can be recorded up the sufficiently high frequency band.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a recording device for recording signals on an information recording medium capable of storing charge.

[Technical background of the invention and its problems]

Various video disc systems have been considered in the past, but all of them, such as optical and capacitive systems, are only for playback and do not allow the user to arbitrarily record or change signals. Met. Therefore, the present inventors first proposed a new video disc system in which signals can be arbitrarily replaced. In this method, as shown in FIG. 1, a semiconductor substrate 2 such as silicon S1 is provided on a conductive substrate 1 such as aluminum, and a semiconductor substrate 2-11 is coated with S1O2) as an insulating film. 8
1. N, using a new recording medium 5 in which layers 4 are sequentially formed,
81 of this recording medium 5. N. A conductive recording needle 6 is provided in contact with the layer 4, and recording is performed by applying a recording signal E8 to the recording needle 6 while moving the recording button 6 and the recording medium 5 relatively. be. When a signal voltage is applied to the recording medium 5 through the recording button 6, the charge on the semiconductor substrate 2 directly under the recording needle 6 reaches the SI, Odzn4 through the 810,1 octopus 3 due to the tunnel effect and is trapped. In this way, the charge is 81. N.

Signal recording is achieved by accumulation in layer 4.

Since a nitrogen depletion layer is formed on the surface of the semiconductor substrate 2 immediately below the accumulated charge in accordance with the accumulated charge, it can be performed, for example, by detecting the capacitance of this depletion layer.

Now, in such a recording device, SL+ of the recording medium 5
The N4/m4 and 5102 layers 3 have a film thickness of approximately 400 mm and 20 A, respectively, and the recording needle 6 is made of glass or sapphire with a thickness of 0.3 mμ.
A thin film of tungsten or the like may be used. The video signal voltage V applied to the recording needle 6 in this case,
The relationship between the electric current flowing through the recording needle 6 and the electric current flowing through the recording needle 6 is shown in FIG. 3A. That is, as the signal voltage V increases, the current flow increases accordingly, and when the voltage reaches a high voltage of 40 to 50 volts or more, an avalanche phenomenon occurs in the semiconductor substrate 2 of the recording medium 5. [Flow knee increases rapidly. When this current exceeds IA, the tip of the recording needle 6 begins to break down due to the current. Therefore, only a low voltage that does not cause current breakdown can be applied to the recording needle 6.

However, if the signal voltage V is set to a low voltage of 20 to 30 volts, there is a problem in that signals in a high frequency band of the order of several MHz of video signals cannot be recorded sufficiently. In addition, even with such a voltage, if there is a pinhole or defect in the sl, N, or layer 4) surface, a dash current may flow to the recording needle 6, and there is a risk of the recording needle 6 being destroyed, resulting in unstable stability. There was a problem that accurate records were not guaranteed.

[Purpose of the invention]

This invention has been made in view of the above points, and an object of the present invention is to provide a recording device that can sufficiently record video signals up to 9 high frequency bands without worrying about current destruction of the recording needle. It is.

[Summary of the invention]

In this invention, a current limiting circuit is provided in the recording needle to prevent a large recording current from flowing through the recording needle even when a high voltage video signal is applied to the recording needle.

[Embodiments of the invention]

The present invention will be explained in detail below with reference to the drawings.

FIG. 2 shows an embodiment of the present invention. In FIG. 8, the recording medium 5 is as explained in FIG. 1, and a semiconductor substrate 81 is provided on a conductive substrate 1. On substrate 2 are 5i02 layers 3.5i8N, layer 4
is formed in the WL order. 813N of this recording medium 5,
Current limiting circuit 14 comprising a recording needle 6 arranged in contact with layer 4
is inserted. The capacitance C8 of the capacitor 10 is, for example, 19F or less, and the resistance value of the resistor 12 is, for example, I
Selected for its high resistance value of MΩ or higher. When a video signal voltage Es to be recorded is applied to the recording needle 6 (usually a signal voltage obtained by converting a carrier signal into an FM signal with a video signal, and a recording voltage of a DC pulse-shaped signal waveform passed through a limiter), this A signal voltage is applied to the tip of the recording needle 6 through a capacitor 10. Note that since the capacitance C8 between the recording needle 6 and the surface of the recording medium 5 is very small, less than io-''pp, a sufficiently large recording signal voltage is applied to the recording medium 5 via the tip of the recording needle 6. Also, at this time, the recording current knee is limited by the large resistor 12, so no large current flows through the recording button 6.Characteristic curve B in FIG. It shows
From this characteristic, even if a large signal voltage is applied, the upper row of N If = I is slight, and even if there is some defect on the surface of the recording medium, it will be enough to destroy the recording needle 6. The current does not reach . Therefore, stable recording can be performed. Furthermore, since a high voltage can be applied, it is possible to sufficiently record up to the high frequency band of the video signal.

〔Effect of the invention〕

As described above, according to the present invention, a large signal voltage can be applied to the recording needle, and recording can be performed sufficiently and stably up to the high frequency band of the video signal. Furthermore, the life of the recording needle can be extended.

In addition, although the above embodiment describes the case of recording on a semiconductor recording medium, the present invention can be similarly applied to the case of using a recording medium capable of accumulating charges such as an electret electrostatic recording medium or a ferroelectric material. Can be done. In addition, although the example uses a recording current limiting circuit using CR, the same purpose can also be achieved by using a circuit that limits the recording current in an electromagnetic circuit by applying the feedback principle of electronic circuits. can be achieved. However, in terms of circuitry, a configuration in which a current limiting circuit using CIl as in the embodiment is inserted into the recording needle can achieve the purpose most easily.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of a conventional recording apparatus, FIG. 2 is a diagram showing an embodiment of the present invention, and FIG. 3 is a diagram showing a conventional recording apparatus. FIG. 3 is a diagram showing the voltage-current characteristics of a recording stylus according to the recording apparatus of the present invention. 1... Conductive substrate, 2... Si semiconductor, 3...
Sin, layer 4...8 i 3 N4 layer 5...
- Recording medium, 6... Recording needle, 10... Capacitor, 12... Resistor, U...' current limiting circuit. Agent Patent Attorney Kensuke Chika (and 1 other person) No.
1 Figure 2 Figure 3

Claims (2)

[Claims] (1) A recording signal is applied to a recording medium capable of accumulating electric charge.
In a recording device that records signals by moving relatively conductive recording needles facing each other, a current limiting circuit for controlling a recording current flowing through the conductive recording needle is provided for the conductive recording needle. Characteristic recording device. (2) The recording device according to claim 1, wherein the current limiting circuit includes a capacitance element and an electric resistance element.