JPS5936304A - Signal reproducer - Google Patents

Abstract

PURPOSE:To reproduce high frequency signals with high quality, by using a reproducing stylus which has the 1st curved surface of a large curvature radius having a contact with a guide wall and the 2nd curved surface of a small curvature radius having a contact with a recorded wall. CONSTITUTION:A signal groove 5 is formed spirally on a record 4 with an approximately V-shaped section. One of these two sections of the groove 5 is used to a recording wall 5a where the digital converted audio signal, for example, is recorded with a fixed amplitude. The other side of the sections is used to a guide wall 5b. A reproducing stylus 6 is basically formed oval, and the curvature radius R of the groove 5 is set large at the side of the wall 5b. While the curvature radius (r) is set small at the side of the wall 5a. Thus the radius (r) approximates to a recessing/projecting signal waveform S0 which is recorded on the wall 5a.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a signal suitable for reproducing a high frequency signal such as a digitally converted audio signal from a record in which the signal groove is recorded in a concave and convex manner. Regarding a playback device.

BACKGROUND TECHNOLOGY AND PROBLEMS Conventionally, recorders for recording and reproducing high-frequency signals that extend outside the audible band have been put into practical use.

In this case, the regenerated needle (1) is as shown in Fig. 1 (Fig. 2 A).
- As shown in the top cross-sectional view on line A', the date hand is used, and the one with the smaller radius of curvature (the one that contacts the recorded signal waveform of the 18X signal groove) is made smaller.
) can be traced correctly. Furthermore, in this case, as shown in FIG. 2, the radius of curvature of the portion (1b) perpendicular to the signal groove (3) of the regeneration needle (1) increases toward the tip, and the regeneration needle (1)
The vibrating area of 1) with the signal groove (3) is made large, so that deformation of the signal groove (3) and wear of the tip of the regenerated needle (1) are reduced.

However, such a device has a limit of reproducing high frequency signals up to about 50 kHz.

If even higher-density recording, such as digital signal recording, is to be performed at frequencies up to several hundred kHz, various difficulties will arise.

Regarding recording, the shape of the conventional cutter needle has been slightly improved, for example, half-speed recording or single-speed recording, etc.
Recording of high frequency signals of kHz or higher is possible.

However, the recorded signal waveform of the unevenness of the signal groove (3) of the record (2) on which such a high-frequency signal is recorded is fine, and the above-mentioned conventional playback needle (]) is also used as a playback needle with a smaller curvature. If it is played back with
Abrasion occurs on the tip of the recycled example, making it difficult to put it into practical use.

If such high-frequency signals are recorded in the horizontal and vertical directions, there is a risk that erroneous information may be obtained due to the inclination of the reproduction needle or the horizontal tracking error angle during reproduction.

By the way, there is an optical method for recording and reproducing, for example, a digitally converted audio signal on a record. However, according to this method, conventional record manufacturing technology cannot be used, the manufacturing cost of the record becomes high, and an expensive playback device must be used.

Purpose of the Invention The present invention has been made in view of the above, and is capable of reproducing high frequency signals, such as digitally converted audio signals, better than a record whose signal grooves are recorded in a concave and convex manner. The purpose of the present invention is to provide a signal reproducing device that can perform the following functions.

Summary of the Invention In order to achieve the above object, the present invention provides a record in which a substantially V-shaped signal groove is formed by a recording wall on which a constant amplitude signal is recorded and a guide wall, and a record with a large radius of curvature that abuts on the guide wall. a first curved surface having a radius of curvature and a second curved surface having a small radius of curvature that contacts the recording wall; when the signal is reproduced by the reproduction needle, the first curved surface It was made to be biased against the wall.

Since the present invention is configured as described above, it is possible to prevent deformation of the signal groove, wear of the reproduction needle, and reproduction of erroneous signals. Signals can be reproduced well.

Embodiment Hereinafter, an embodiment of the signal reproducing apparatus according to the present invention will be described with reference to FIG. 3 and subsequent figures.

In FIGS. 3 and 4, (4) is the record played in this example. A spiral signal groove (5) is formed on this record (4). This signal groove (5) has a substantially V-shaped cross section, and one wall thereof is a recording wall (5) where, for example, a digitally converted audio signal is recorded so as to have a constant amplitude.
5a), and the other wall is a guide wall (5b).

This record (4) is created, for example, in the following steps.

First, the audio signal is converted into a digital signal and this is supplied to the cutting machine. Then, this cutting machine engraves the digitally converted audio signal on the lacquer disc as a signal with a constant amplitude. In this case, in a 45-45 type cutting machine, for example, a digitally converted audio signal is supplied only to the R channel, and not to the L channel. The above-mentioned record (4) is molded from this lacquer disc through a normal record duplication process.

Moreover, in FIGS. 3 and 4, (6) is a regenerated needle that constitutes this example.

This regenerated needle (6) is basically outside an ellipse, as shown in FIG. The radius of curvature R on the side of the recording wall (5a) is large, and the radius of curvature r on the side of the recording wall (5a) is
It is made smaller by approaching the uneven signal waveform So recorded in 5a). The numerical values shown in FIG. 5 are an example when the highest frequency of the recording signal is 128 kHz, and this numerical value is arbitrarily set depending on the frequency of the recording signal.

In addition, a predetermined lateral pressure F is applied to this reproduction needle (6) in the direction from the recording wall (5a) side to the guide wall (5b) side. Force may be used, or lateral pressure F
A device for adding this may be provided on the tone arm or the like.

The playback needle (6) is configured to trace the signal groove (5) of the record (4) in the state shown in FIGS. 3 and 4.

FIG. 6 shows an example of a cartridge to which a regeneration needle (6) is attached. In the same figure, (7) is the regenerated needle (6
) are several cantilevers, (8) is a piezoelectric element, (8) is a piezoelectric element, (
9) fl-j: Dunnoya-1 and θ0 are output terminals.

Vibration caused by the reproduction needle (6) tracing the signal groove (5) of the record (4) is transmitted to the piezoelectric element (8) through the cantilever (7). The one-pressure type element (8) has an appropriate stiffness so as to cause deflection at high frequencies. Eventually, a 1+ raw signal (signal recorded on the recording wall (5b)) is obtained from this piezoelectric element (8), and this is output to the terminal (10).The damper (9) serves as a 4-axis pivot point. .

The signal obtained at this terminal θ1 is converted into an analog signal by a DA converter, and the original audio signal is reproduced.

This example is constructed as shown below, and the signal groove (5) is approximately V-shaped, one wall of which is a recording wall (5a), and the other wall is a guide wall (5b). The record (4) is moved by a reproduction needle (6) whose radius of curvature r on the side of the recording wall (5a) is made smaller so that it approaches the signal waveform So recorded on this recording wall (5a).
), it is possible to faithfully reproduce digitally converted audio signals, which are recorded high-frequency signals. Moreover, this regenerating needle (6) has a large radius of curvature R on the guide wall (5b) side, and also has a lateral pressure F.
The stylus is biased toward the guide wall (5b), and the stylus pressure applied to the stylus tip is greater on the guide wall (5b) and less on the recording wall (5a). This prevents the signal waveform So generated from being damaged and the reproduction needle (6) itself from being rapidly worn out. Furthermore, as mentioned above, one wall of the signal groove (5) is used as a recording wall (5b), and the other is used as a guide wall (5a) on which no signal is recorded, and neither wall is recorded with a signal. So, regenerate needle (6)
Even if it is slightly rotated and deviated from the predetermined position as shown in FIG. 4, an erroneous signal will not be obtained.

In the above-mentioned embodiment, an example was described in which a digitally converted audio signal is recorded on the record (4), but other information signals, data signals, etc. may be used as the recording signal. Further, the shape of the signal groove (5) of the record (4) may be as shown in FIGS. 7A, B, and C.

Effects of the Invention As is clear from the embodiments described above, according to the signal reproducing device according to the present invention, the signal groove is approximately V-shaped, one wall of which is used as a recording wall, and the other wall is used as a guide wall. Since the record is played back by a playback needle whose radius of curvature on the recording wall side is made small so that it approaches the signal waveform recorded on this recording wall, even if the recorded signal is a high frequency signal, the fidelity is maintained. can be played back. Moreover, this reproducing needle has a narrow radius of curvature on the guide wall side and is biased toward the guide wall side by the lateral pressure, so that the stylus pressure applied to the tip of the needle is greater on the guide wall side and less on the recording wall side. Therefore, the signal waveform recorded on the recording wall may be damaged by the playback needle,
The regenerated needle itself will not wear out rapidly. Also,
One wall of the signal groove is used as a recording groove, and the other wall is used as a guide wall where no signal is recorded.Since no signals are recorded on either wall, even if the position of the playback needle deviates from the predetermined position, Never get a false signal.

Further, according to the present invention, it is possible to use conventional record manufacturing technology (for example, analog cutting with one cut), and the unit cost of manufacturing records can be lower than that using an optical method.

There is also the benefit of being able to use mostly conventional players for playback.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of the regenerated needle used in the example in Figure 2;
The figure is a cross-sectional view of the main part of a conventional signal reproducing device, FIGS. 3 and 4 are a cross-sectional view and a top view of the main part of the signal reproducing device according to the present invention, and FIG. 5 is used for the example shown in FIG. Cross-sectional view of regenerated needle,
FIG. 6 is a side view showing an example of the cartridge, and FIG. 7 is a sectional view showing another example of the signal groove. (4) is a record, (5) is a signal groove, (5a) is a recording wall, (5b) is a guide wall, (6) is a reproduction needle, and F is a single stick.

Claims (1)

[Claims] A record in which a substantially V-shaped signal groove is formed by a recording wall on which a constant amplitude signal is recorded and a guide wall, a first curved surface having a large radius of curvature that contacts the guide wall, and a record wall that contacts the recording wall. A reproducing needle is provided with a second curved surface having a small radius of curvature in contact with the reproducing needle, and when reproducing the signal with the reproducing needle,
A signal reproducing device characterized in that the first curved surface is biased toward the guide wall.