JP3442000B2 - Optical disk information recording / reproducing device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording / reproducing apparatus for an optical disc recording medium.

[0002]

2. Description of the Related Art With the recent rapid development of multimedia-related technologies, optical discs that are easy to handle and have a relatively large storage capacity are often used. Figure 9
FIG. 1 shows a block diagram of a general optical disc information recording / reproducing apparatus.

In FIG. 9, 90 is a disk, 91 is a recording control circuit, 93 is an optical head, 94 is a head control circuit, 95 is a spindle control circuit, 96 is a spindle motor, and 97 is an abnormality detection circuit. , 99 indicates a buffer memory, respectively.

In FIG. 9, when the head control circuit 94 detects a drive abnormality such as off-track or defocus and the abnormality detection circuit 97 notifies an abnormality signal 98,
Alternatively, when the recording control circuit 91 collates the written information 92a temporarily stored in the buffer memory 99 with the information 92b read from the disc by the verify operation of the drive and determines that there is an inconsistency,
Normal information recording is assured by re-recording on the disc 90 the information that has already been written once during writing.

[0005]

However, in the optical disc information recording / reproducing apparatus as described above, the information is recorded by alternately performing the recording and the reproducing on the optical disc by the verify operation, so that the disc originally has it. There is a limitation that the information can be recorded only at about half the recording speed.

When an optical disk recording / reproducing apparatus is built in a camera and used, for example, a Coriolis force is generated on the rotating disk by the pan operation of the camera. Then, due to the action of such Coriolis force, the disc clamp is released or the disc is largely warped, so that the tilt of the disc with respect to the optical head is largely changed at a low frequency, and a normal recording mark is not formed on the disc. And other obstacles occur. in this case,
Even if no error is detected in the drive during recording, there is a problem that some information cannot be reproduced normally during reproduction.

In order to solve the above-mentioned problems, the present invention can maintain the integrity of the recorded information without performing the verify operation, and further, the Coriolis force acts to cause the tilt due to the deformation of the disk or the like. It is an object of the present invention to provide an optical disc information recording / reproducing apparatus capable of recording / reproducing normal information even when it becomes large.

In order to achieve the above object, an optical disk information recording / reproducing apparatus according to the present invention comprises an optical head for recording information on a disk, a head control means for controlling the position of the optical head with respect to the disk, and a temporary information storage. Storage means for storing and sending to the optical head, spindle motor for rotating the disk, spindle control means for controlling the rotation of the spindle motor, and Coriolis applied to the disk.
Coriolis force detection means for detecting force and Coriolis force detection hand
Depending on the magnitude of the Coriolis force detected by the step,
Control the recording to the disk and the reading of information from the storage means
Optical disk information recording / reproducing apparatus having recording control means
In the recording control means, when the magnitude of the Coriolis force detected by the Coriolis force detection means exceeds a predetermined threshold value, the optical head stops recording on the disk and reading information from the storage means. When the magnitude of the Coriolis force detected by the detecting means becomes less than or equal to a predetermined threshold value, the reading of information from the storage means and the recording on the disc by the optical head are restarted, and the Coriolis force detecting means
Is an angular velocity sensor that detects the angular velocity as a disturbance, and
Angular velocity output from velocity sensor and spindle control means
Coriolis force based on the disc rotation speed output from
It is characterized by being configured by a calculator for calculation .

With such a configuration, the Coriolis force acting on the disc is constantly detected, and the tilt amount generated on the disc increases due to the large Coriolis force applied, and normal writing of information by the optical head cannot be performed. To temporarily store the information in the storage means,
By recording on the disc itself after confirming that the Coriolis force detected with high precision has been restored to a level that allows normal writing, the information on the disc can be in a normal state without performing the verify operation. It is possible to keep

Further, in the optical disc information recording / reproducing apparatus according to the present invention, when the magnitude of the Coriolis force detected by the Coriolis force detecting means in the recording control means exceeds a predetermined threshold value, the optical head writes the disc. It is preferable that the reading of the information from the recording and storage means is interrupted, and the reading of the information from the storage means and the recording on the disc by the optical head are resumed after a certain time has elapsed. When the optical disk recording / reproducing device is used by being built in a camera, when the Coriolis force detected by the Coriolis force detecting means exceeds a predetermined threshold value and a predetermined time has elapsed, the Coriolis force becomes large. This is because it is empirically recognized that the value becomes less than or equal to a predetermined threshold value.

[0011]

Further, in the optical disk information recording / reproducing apparatus according to the present invention, the Coriolis force detecting means detects an acceleration as a disturbance, an acceleration value output from the acceleration sensor, and a disk output from the spindle control means. It is preferably configured by a computer that calculates the Coriolis force based on the rotation speed. This is because it is possible to realize a small-sized and low-cost Coriolis force detection unit by using a general acceleration sensor.

Further, in the optical disk information recording / reproducing apparatus according to the present invention, the two acceleration sensors are arranged such that the center of rotation of the two acceleration sensors is the center of rotation, and the acceleration of the rotational movement about the center of rotation is centered. It is preferable that the two acceleration sensors are arranged so as to face each other so that positive and negative are output. This is to detect the acceleration due to the pan operation, which is greatly affected by the Coriolis force.

[0014]

[0015]

Further, in the optical disc information recording / reproducing apparatus according to the present invention, the Coriolis force detecting means estimates the Coriolis force based on the displacement sensor and the displacement sensor that detects the displacement amount of one point on the disc. It is preferably composed of a vessel. This is because it is possible to realize a small-sized and low-cost Coriolis force detection unit by using a general displacement sensor.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An optical disk information recording / reproducing apparatus according to embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a block diagram of an optical disc information recording / reproducing apparatus according to the embodiment of the present invention. In FIG. 2, 1 is a disk drive, 3 is an optical head, 5 is a disk, 6 is a spindle motor, 8 is an optical disk drive integrated camera, 31 is a head control circuit, 6
Reference numeral 1 is a spindle control circuit, and 71 is an angular velocity sensor.

First, in the optical disk drive integrated camera 8 for recording an image on the disk 5, the optical head 3 is installed in the vicinity of the disk 5 so as to be movable in the radial direction of the disk 5, and is controlled by the head control circuit 31. An actuator 32 (not shown) built in the head 3
Thus, the laser is focused, and a recording signal as information is formed as a mark 52 (not shown) on a track 51 (not shown) formed on the disk 5.

The disk 5 is fixed to a spindle motor 6 and is controlled by a spindle control circuit 61 to have a predetermined rotation speed. The angular velocity sensor 71 is fixed near the disc drive 1 and constantly detects the angular velocity applied to the optical disc drive integrated camera 8 during recording / reproduction of an image.

The Coriolis force detector 77 is an angular velocity sensor 71.
By calculating the Coriolis force acting on the disk 5 from the angular velocity information 75 from the disk and the disk rotation speed information 62 from the spindle control circuit 61, normal recording cannot be performed on the disk 5 set as a threshold value in advance. A comparison with the Coriolis force value is performed, and when the calculation result in the Coriolis force detector 77 exceeds the threshold value, a detection signal 78 is transmitted to the recording control circuit 22.

Specifically, in FIG. 1, the video signal 2 input from the camera is coded by the coding circuit 21 and temporarily stored as a recording signal 23 in the buffer memory 4 which is a storage means, and recording control is performed. It is sent to the optical head 3 by the circuit 22 and recorded on the disk 5.

Next, the optical disk drive integrated camera 8
The angular velocity ω is added to the by the pan operation performed by the cameraman. At this time, Coriolis force acts on the disk 5 rotating inside, and the disk 5 is deformed as shown in FIG.

Here, the Coriolis force will be supplementarily described. The Coriolis force acting on a mass point is proportional to the moving speed of the mass point and the angular velocity ω applied to the system, and the peripheral speed due to the rotation of the mass point on the disk 5 is V, and the mass point is Let m be the mass of
The Coriolis force acting is represented by 2 mVω. Therefore, by integrating the Coriolis force acting on the mass point over the entire surface of the disk 5, the Coriolis force acting on the entire disk 5 can be calculated. The Coriolis force is a very large force, for example, the disc rotation speed is 5000.
rpm, angular speed of pan movement of cameraman 300 deg /
In the case of sec, the total torque Tc applied to the entire surface of the disk 5 is about 1 kg.
When the disc 5 having a diameter of 12 cm, such as a CD or a DVD, is completely restrained by the spindle motor 6, the deformation amount X of the end portion of the disc 5 becomes about 0.8 mm.

When a large Coriolis force is applied as described above, the amount of tilt with respect to the optical head 3 increases due to the deformation of the disk 5, and the optical head 3 focuses the laser on the disk 5 to form a normal shape. It becomes impossible to form the mark 52. The deformation of the disk 5 is
It has been confirmed that there is a strong correlation with the Coriolis force acting, and it is possible to determine the deformation condition of the disk 5 that makes normal recording by the optical head impossible based on the Coriolis force acting on the disk.

When a large Coriolis force acts and a detection signal 78 is sent from the Coriolis force detector 77 to the recording control circuit 22, the recording control circuit 22 stops the recording on the disk 5 by the optical head 3 and the buffer memory 4 The reading of the recording signal from is stopped, and the recording signal is accumulated in the buffer memory 4 by this. At the same time, the address of the last point of the information sequence in which information is normally recorded is stored before the recording on the disk 5 is stopped, the optical head 3 is moved to the address, and the recording is resumed in a standby state.

When it is confirmed that the Coriolis force applied by the Coriolis force detector 77 has fallen below a predetermined threshold value, the transmission of the detection signal 78 is stopped. As a result, the recording control circuit 22 restarts reading from the buffer memory 4 and recording on the disk 5 by the optical head 3. Here, since the recording speed of the recording signal on the disk 5 by the optical head 3 is set to be faster than the recording speed of the recording signal of the buffer memory 4, the recording signal accumulated in the buffer memory 4 has passed a certain time after recording is restarted. At that time, all the data is recorded on the disk 5, and the normal video signal recording operation is resumed.

In this embodiment, it is detected that the Coriolis force calculated by the Coriolis force detection means is below a predetermined threshold value for reading from the buffer memory 4 and resuming recording on the disk 5 by the optical head 3. I am going,
Since the large angular velocity due to the pan operation of the camera is instantaneous and the continuous pan operation hardly occurs in actual use, the recording control circuit 22 stops the recording and then restarts the recording after a lapse of a certain time. May be

In order to eliminate the influence of the Coriolis force as early as possible, recording on the disk 5 by the optical head 3 is stopped and reading of a recording signal from the buffer memory 4 is stopped, and at the same time, the spindle control circuit is stopped. It is also conceivable to control the spindle motor 6 by 61 to temporarily stop the rotation thereof.

Further, according to the present embodiment, only the pan operation direction of the optical disk drive integrated camera 8 has been described, but similarly, the angular velocity of the camera in the rolling operation direction in which the Coriolis force influences also occurs. This can be dealt with by adding an angular velocity sensor 71 for detecting

It is also conceivable to use an acceleration sensor 72 instead of the angular velocity sensor 71. FIG. 4 shows a block diagram of an optical disc information recording / reproducing apparatus according to an embodiment of the present invention. FIG. 4 is basically the same as FIG. 1 except that an acceleration sensor 72 is used instead of the angular velocity sensor 71.

The acceleration sensors 72a and 72b are, as shown in FIG. 5, centered on the rotation center O when the cameraman pans the optical disk drive integrated camera 8.
The cameras 8 are installed to face each other in the front-rear direction by 180 degrees. When the camera 8 vibrates in the vertical direction, the outputs of the acceleration sensors 72a and 72b are installed in a direction in which plus and minus are output with opposite values. The acceleration applied to the camera 8 is constantly detected.

The Coriolis force detector 77 comprises an acceleration sensor 7
The angular velocity ω is calculated by the formula ω = (a / r) ^1/2 based on the acceleration a detected by 2a and the distance r from the rotation center point O during the pan operation to the acceleration sensor 72. The acceleration sensors 72a and 72b output acceleration values not only when panning but also when the camera 8 vibrates in the vertical direction.
In the latter case, the outputs of the acceleration sensors 72a and 72b are output with the opposite positive and negative values, whereas in the former case, the acceleration sensors 72a and 72b have the same positive and negative values, and thus the angular velocity ω is generated. Can be detected. The Coriolis force acting on the disc 5 can be calculated based on the angular velocity ω and the disc rotation speed from the spindle control circuit 61, and the Coriolis force threshold value that makes normal recording on the disc 5 impossible. By performing the comparison, when the calculation result exceeds the threshold value, the detection signal 78 is transmitted to the recording control circuit 22. Hereinafter, since the recording operation is the same, detailed description thereof will be omitted.

Further, it is conceivable to use the tilt sensor 73 instead of the angular velocity sensor 71. FIG. 6 is a block diagram of an optical disc information recording / reproducing apparatus according to another embodiment of the present invention. FIG. 6 is basically the same as FIG. 1, except that a tilt sensor 73 is used instead of the angular velocity sensor 71.

The tilt sensor 73 is installed near the optical head 3 so as to be movable together with the optical head 3 in the radial direction of the disk 5, and always detects the tilt amount at the position of the optical head 3 during image recording / reproduction. .

The Coriolis force detector 77 is a tilt sensor 7
The Coriolis force is estimated from the tilt amount information 78 from 3 and the disk radial position information 32 of the optical head 3 obtained from the head control circuit 31. As described above, the Coriolis force and the deformation amount of the disk 5 are correlated with each other, and therefore it is possible to estimate the Coriolis force acting based on the tilt amount generated at a certain radial position of the disk. The estimated Coriolis force is compared with the threshold value of the Coriolis force at which normal recording cannot be performed on the disk 5, and when the calculation result exceeds the threshold value, a detection signal 78 is transmitted to the recording control circuit 22. To do. Hereinafter, since the recording operation is the same, a detailed description thereof will be omitted.

On the other hand, it may be considered that the angular velocity sensor 71 is not used. FIG. 7 is a block diagram of an optical disc information recording / reproducing apparatus according to another embodiment of the present invention. FIG. 7 shows FIG.
The basic difference is that the angular velocity sensor 71 is not used.

The Coriolis force detector 77 determines the disk 5 from the disk rotation speed information 62 from the spindle control circuit 61.
Estimate the Coriolis force acting on. When the Coriolis force acts on the disk 5, bending torque is applied to the rotating shaft of the spindle motor 6 and twisting occurs between the rotating shaft of the spindle motor 6 and the bearing, so that the rotation of the disk 5 rapidly decreases. Since the rate of decrease in the rotational speed from the constant rotational speed has a strong correlation with the magnitude of the Coriolis force, it is possible to estimate the Coriolis force based on the change in the rotational speed. The estimated Coriolis force and the Coriolis force at which normal recording on the disk 5 cannot be performed are also compared with a threshold value. When the estimated result exceeds the threshold value, a detection signal 78 is transmitted to the recording control circuit 22. . Since the recording operation is the same, a detailed description will be omitted.

Further, the displacement sensor 74 may be used instead of the angular velocity sensor 71. FIG. 8 is a block diagram of an optical disc information recording / reproducing apparatus according to another embodiment of the present invention. 8 is basically the same as FIG. 1 except that a displacement sensor 74 is used instead of the angular velocity sensor 71. The displacement sensor 74 is installed near the end of the disc 5 and constantly detects the amount of displacement at any one point on the disc 5 during video recording and reproduction.

The Coriolis force detector 77 includes a displacement sensor 74.
The Coriolis force is estimated from the displacement amount information 79 from. As described above, the Coriolis force and the amount of deformation of the disk 5 have a strong correlation, and the acting Coriolis force can be estimated based on the amount of displacement of one point on the disk 5. The estimated Coriolis force is compared with the threshold value of the Coriolis force at which normal recording cannot be performed on the disk 5, and when the calculation result exceeds the threshold value, a detection signal 78 is sent to the recording control circuit 22.
To send. Since the recording operation is the same, a detailed description will be omitted.

As described above, according to the present embodiment, when the verify operation is not performed in order to speed up the recording on the disc, the Coriolis force acting on the disc is always detected, so that the large Coriolis force is detected. When the optical head cannot write the normal information due to the addition of the magnetic field, the information is temporarily stored in the storage means, and the Coriolis force is large enough to write normally. Since it is recorded on the disc itself after it is detected that the information has been restored, the information on the disc can be kept in a normal state.

[0041]

As described above, according to the optical disk information recording / reproducing apparatus of the present invention, the Coriolis force acting on the disk is constantly detected when the verify operation is not performed in order to speed up the recording on the disk. This increases the amount of tilt generated on the disc due to the large Coriolis force applied, and when normal writing of information by the optical head is not possible, the information is temporarily stored in the storage means and the Coriolis force is normal. Since it is recorded on the disc itself after it is detected that the disc has been restored to a size such that it can be written properly, the information on the disc can be kept in a normal state.

[Brief description of drawings]

FIG. 1 is a configuration block diagram of an optical disc information recording / reproducing apparatus according to an embodiment of the present invention.

FIG. 2 is a top view and a side view of an optical disk drive integrated camera using the optical disk information recording / reproducing apparatus according to the embodiment of the present invention.

FIG. 3 is a side view of the disc when the Coriolis force is applied in the optical disc information recording / reproducing apparatus according to the embodiment of the present invention.

FIG. 4 is a configuration block diagram of an optical disc information recording / reproducing apparatus according to an embodiment of the present invention.

FIG. 5 is a top view and a side view of an optical disk drive integrated camera using the optical disk information recording / reproducing apparatus according to an embodiment of the present invention.

FIG. 6 is a configuration block diagram of an optical disk information recording / reproducing apparatus according to another embodiment of the present invention.

FIG. 7 is a configuration block diagram of an optical disc information recording / reproducing apparatus according to another embodiment of the present invention.

FIG. 8 is a configuration block diagram of an optical disc information recording / reproducing apparatus according to another embodiment of the present invention.

FIG. 9 is a configuration block diagram of a conventional optical disc information recording / reproducing apparatus.

[Explanation of symbols]

1 disk drive 2 video signals 3,93 Optical head 4,99 buffer memory 5,90 discs 6,96 spindle motor 21 Encoding circuit 22, 91 Recording control circuit 31, 94 Head control circuit 61, 95 Spindle control circuit 71 Angular velocity sensor 72 Accelerometer 73 Tilt sensor 74 Displacement sensor 77 Coriolis force detector 97 Abnormality detection circuit

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI H04N 5/781 G11B 19/28 B // G11B 7/004 H04N 5/781 510J 19/28 (72) Inventor Toshiaki Nakamatsu Osaka Fuchu Kadoma City 1006 Kadoma Matsushita Electric Industrial Co., Ltd. (72) Inventor Jun Takeuchi Osaka Kadoma 1006 Kadoma Matsushita Electric Industrial Co., Ltd. (56) Reference JP-A-11-339371 (JP, JP, 339371) A) JP-A-3-74973 (JP, A) JP-A-11-18040 (JP, A) JP-A-10-345022 (JP, A) JP-A-10-84529 (JP, A) JP-A-63 -141463 (JP, A) JP 61-180952 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04N 5/00-5/95 G11B 3/00-33/14

Claims (4)

(57) [Claims] 1. An optical head for recording information on a disc, a head control means for controlling a position of the optical head with respect to the disc, a storage means for temporarily storing information and sending it to the optical head, A spindle motor for rotating the disk, a spindle control means for controlling the rotation of the spindle motor, a Coriolis force detecting means for detecting the Coriolis force applied to the disk, and a magnitude of the Coriolis force detected by the Coriolis force detecting means. An optical disc information recording / reproducing apparatus comprising: a recording control unit for controlling recording on the disc and reading information from the storage unit, wherein the recording control unit detects the Coriolis force detecting unit. When the magnitude of the Coriolis force exceeds a predetermined threshold value, the optical head is activated. Interrupting the reading of information from the recording and the storage means to said disk,
When the magnitude of the Coriolis force detected by the detecting unit becomes equal to or smaller than a predetermined threshold value, the reading of information from the storage unit and the recording on the disc by the optical head are restarted, and the Coriolis force detecting unit Is composed of an angular velocity sensor that detects an angular velocity as a disturbance, and a computer that calculates the Coriolis force based on the angular velocity output from the angular velocity sensor and the disk rotational speed output from the spindle control means. Optical disc information recording / reproducing apparatus. 2. The Coriolis force detecting means detects the Coriolis force based on an acceleration sensor that detects acceleration as a disturbance, an acceleration value output from the acceleration sensor, and a disk rotation speed output from the spindle control means. The optical disc information recording / reproducing apparatus according to claim 1, which is configured by a calculator. 3. The two acceleration sensors are arranged so that the center of rotation of the two acceleration sensors is the center of rotation, and the accelerations of the rotational motion centered on the center of rotation are output in the same positive and negative directions. 3. The optical disc information recording / reproducing apparatus according to claim 2, wherein the two acceleration sensors are arranged to face each other. 4. In the recording control means, when the magnitude of the Coriolis force detected by the Coriolis force detection means exceeds a predetermined threshold value, recording on the disk by the optical head and recording from the storage means are performed. interrupting the reading of the information, the optical disk information recording and reproducing apparatus according to any one of claims 1-3 resuming the recording to the disk by the read and the optical head of the information from the storage means after a predetermined time has elapsed .