JPH09161388A - Optical disk discriminating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatomize the initialization and the mode setting of an optical disk device by providing a disk surface reflectivity measuring means and a discriminating device, etc., to automatically discriminate whether a disk is a single-sided disk or a stuck double-sided disk. SOLUTION: A disk surface reflectivity measuring means 4 is arranged at the fixed position of an opposite side across an optical disk 1 together with an optical head 3 to measure the reflectivity of the surface of the disk and transmits the reflectivity 101 to a distriminator 7, which compares the transmitted reflectivity with values preliminarily fixed in the internal part of the discriminator 7 and transmits the optical disk discrimination signal 102 expressing the kind of the optical disk 1 to a control microcomputer 6. The computer 6 automatically executes the initialization and the setting of various kinds of modes of the optical disk device according to the kind of the single-sided disk or the double-sided disk to be expressed by the optical disk discrimination signal 102.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc recording / reproducing apparatus or an optical disc reproducing apparatus, and more particularly to an optical disc discriminating device for discriminating the type of an optical disc in a device which may be used by mounting plural types of optical discs. .

[0002]

2. Description of the Related Art In recent years, various kinds of optical disks such as compact disks (CD) and laser disks (LD) have been commercialized, and digital video disks (DVD).
The following new optical discs have been proposed. In addition, a device that can reproduce these multiple discs was commercialized, and C
There are players that can reproduce both D and LD. In the case of a CD and an LD, the disc diameters are significantly different, 120 mm and 300 mm, so it is not difficult to make a distinction when the optical disc is mounted in the device, but if the disc sizes are exactly the same, it is possible to make a mechanical discrimination. Is difficult to do. If it is stored in a cartridge such as a magneto-optical disk, you can make a distinction mechanically by marking the cartridge for identification (for example, making a hole in a specific part of the cartridge). In Although,
In the CD and the currently proposed DVD, the optical disc is exposed and the disc diameter is the same, and it is difficult for the reproducing apparatus to mechanically determine these. The reason that the optical disk is not inserted into the protective cartridge is to suppress the compatibility with the handling of the conventional CD and the medium cost.

Conventionally, there have been proposed several methods for optically discriminating such optical disks of the same size. For example, in Japanese Laid-Open Patent Publication No. 62-76061, the signal level obtained from the optical head is measured with the configuration shown in FIG. 3 while the objective lens reaches the vicinity of the in-focus position during focus search. There is a description example of a playback device that determines the type. In this conventional example, the optical disk 1
Are driven to rotate by a spindle motor 8. An optical head 3 is installed below the optical disk 1 so as to move in the radial direction of the optical disk 1 and to the mountain.
The signal obtained from the optical head 3 is the signal generation circuit 2
0, and the RF signal 103 and the focus error signal 105 corresponding to the pit train recorded on the optical disc 1,
The tracking signal 106 is generated. When the optical disc 1 is reproduced, the focus servo must first be applied to the optical disc 1. First, the objective lens of the optical head 3 is forcibly moved in the focusing direction to focus 0K.
The signal generation circuit 23 monitors the level of the RF signal 103 obtained from the signal generation circuit 20 at this time, and when it becomes equal to or higher than a predetermined value, that is, when the objective lens reaches the in-focus position, the focus OK signal 108. To the servo circuit 24. At this time, the servo circuit 24 turns on the focus servo based on the focus error signal 105 output from the signal generation circuit 20. When the focus servo is turned on, the tracking signal 106 is output from the signal generation circuit 20.
The tracking servo is applied by 4 and the RF signal 10
3 is a signal modulated by the signal recorded on the track of the optical disc 1. The RF signal 103 is further demodulated and error-corrected by the signal processing circuit 22, and becomes a reproduced signal 107. At this time, the RF signal 103 is also supplied to the discrimination circuit 21, and the signal level is measured. The discriminating circuit 21 discriminates the type of the optical disc 1 based on the difference in the signal level, and sends the servo suppression signal 1 to the servo circuit 24.
04, etc. are set and various internal settings are made.

[0004]

By the way, in recent years, various types of optical disks have been commercialized or proposed which cannot be discriminated only by the difference in the reflectivity of the optical disk at the time of focus pull-in as in the conventional example. For example, a large amount of data such as digital moving images is being handled on a personal computer, and a new disc having a high recording density has been proposed. Digital video disc (DV
D) is the mainstream and is an optical disc having a physical density about four times that of the present optical disc, but the disc reflectivity itself is not much different from the present one. There are also double-sided discs in which thin single-sided discs are attached back to back and optical discs in which the disc recording layers are multilayered in order to perform reproduction for a longer time. Of course, the user who tries to play the optical disc may manually input the disc type, but sometimes the user makes a mistake,
In addition, it is not desirable because it is time-consuming.

The present invention provides an optical disc automatic discriminator capable of automatically discriminating between a single-sided disc and a double-sided laminated disc. In an optical disc device incorporating the disc, a user manually inputs the disc type. The purpose is to obtain the convenience of being able to quickly reproduce the information without applying the information.

[0006]

An optical disc discriminator of the present invention is an optical disc recording / reproducing apparatus for lowering a disc tray and loading an optical disc, or an optical disc discriminating device in an optical disc reproducing apparatus. A disk surface reflectance measuring unit which is installed on the opposite side of the optical head arrangement side and which measures the reflectance of the optical disk surface on the opposite side of the optical head arrangement side, and the optical disk reflection by the disk surface reflectance measuring unit. It has a discriminator for measuring the rate and outputting an optical disc type signal for discriminating the type of the loaded optical disc according to the measured reflectance.

The optical disc type signal for discriminating the type of the optical disc is also an optical disc type signal for discriminating whether the loaded optical disc is a single-sided disc or a double-sided bonded disc.

Further, the optical disc discriminating device of the present invention is an optical disc discriminating device in an optical disc recording / reproducing apparatus or an optical disc reproducing device having a front loading mechanism for sliding the disc tray to load the optical disc. A disk surface reflectance measuring unit that is installed on the opposite side of the head arranging side and measures the reflectance of the optical disk surface on the opposite side of the optical head arranging side, and the disk surface reflectance measuring unit when loading the optical disk, While sliding the disc tray, continuously measure the reflectance of the optical disc,
It has an A / D conversion that digitizes the measured change in reflectance and a microcomputer that analyzes the reflectance distribution on the digitized optical disk surface and determines the type of the loaded optical disk.

The microcomputer also analyzes the reflectance distribution on the surface of the digitized optical disc to determine whether the loaded optical disc is a single-sided disc or a double-sided disc.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION
In an optical disk recording / reproducing apparatus or an optical disk reproducing apparatus in which a disk tray is lowered to load an optical disk, the disk surface reflectance measuring means for measuring the reflectance of the optical disk surface on the side opposite to the side where the optical head is arranged is the optical disk loading. Then, the reflectance of the surface of the optical disc on the side where the optical head is not placed is measured, and the reflectance value is input to the discriminator and compared with a predetermined value inside the discriminator to determine the optical disc. Determine the type of.

Further, in the optical disc discriminating device of the present invention, in the optical disc recording / reproducing apparatus or the optical disc reproducing apparatus having a front loading mechanism for loading the optical disc by sliding the disc tray, the optical head is loaded when the optical disc is loaded. The disk surface reflectance measuring means for measuring the reflectance of the optical disk surface on the side opposite to the arrangement side measures the change in the reflectance of the optical disk surface within the range moved by loading, and the reflectance is measured by an A / D converter. The type of optical disc is automatically discriminated by digitizing and analyzing the digitized reflectance by a microcomputer.

[0012]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a first embodiment of the present invention. The optical disc 1 is placed on the disc tray 2 and moved so that the center hole 9 of the optical disc is directly above the spindle motor 8. At this point, the optical head 3 and the optical disk 1 are placed at a fixed position on the opposite side, and the disk surface reflectance measuring means 4 causes a portion of the disk surface at a fixed position in the radial direction (for example, unrecorded outside the clamp part). The reflectance 101 of a region or the like) is measured. The disk surface reflectance measuring means 4 may be configured, for example, such that the light emitted from the LED is received by a photodetector. The reflectance 101 is input to the discriminator 7 and compared with a predetermined value in the discriminator to output an optical disc discriminating signal 102 indicating the type of the optical disc 1. The optical disc discriminating signal 102 is fetched by the control microcomputer 6 to perform initial setting and various mode setting of the optical disc device according to the type of the detected optical disc. As a result, the convenience of promptly reproducing information can be obtained without the user having to manually input the disc type.

FIG. 2 shows a second embodiment of the present invention. The optical disc 1 is placed on the disc tray 2 and moved in the loading direction (the direction in which the disc tray is pulled into the optical disc device) as shown in the figure. At this time, the reflectance 101 of the disk surface is measured by the disk surface reflectance measuring means 4 placed at a fixed position on the opposite side with the optical head 3 and the optical disk 1 sandwiched therebetween. Since the optical disc 1 is moved by the disc tray 2, the temporal change of the reflectance 4 becomes equal to the reflectance distribution on the disc surface. The reflectance 101 is digitized by the A / D converter 5 and taken into the control microcomputer 6. The control microcomputer analyzes the loaded optical disk surface reflectance distribution and determines the type of disk. Then, similar to the first embodiment, the initial setting and various mode settings of the optical disk device are performed according to the detected type of the optical disk. As a result, the convenience that the information can be quickly reproduced can be obtained without the user having to manually input the disc type.

[0014]

As described above, according to the present invention, since it is possible to automatically discriminate between a single-sided disc and a double-sided laminated disc, an optical disc device incorporating this disc has the trouble of manually inputting the disc type by the user. There is an effect that convenience can be obtained in which information can be quickly reproduced without being applied.
In addition, automation also has the effect of preventing erroneous settings of the disc type by the user.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of an optical disc discriminator of the present invention.

FIG. 2 is a block diagram showing a second embodiment of the optical disc discriminator of the present invention.

FIG. 3 is a block diagram showing a conventional optical disc discriminator of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 optical disk 2 disk tray 3 optical head 4 disk surface reflectance measuring means 5 A / D converter 6 control microcomputer 7 discriminator 8 spindle motor 9 center hole 20 signal generation circuit 21 discrimination circuit 22 signal processing circuit 23 focus OK signal generation Circuit 24 Servo circuit 101 Reflectivity 102 Optical disc discrimination signal 103 RF signal 104 Servo control signal 105 Focus error signal 106 Tracking signal 107 Playback signal 108 Focus OK signal

Claims (4)

[Claims] 1. An optical disc recording / reproducing device for lowering a disc tray to load an optical disc, or an optical disc discriminating device in an optical disc reproducing device, wherein when the optical disc is loaded, the optical disc is sandwiched between the optical head and the opposite side. A disk surface reflectance measuring unit that is installed and measures the reflectance of the optical disk surface on the side opposite to the optical head arrangement side, and measures the optical disk reflectance by the disk surface reflectance measuring unit, and according to the measured reflectance. An optical disc discriminator having a discriminator that outputs an optical disc type signal for discriminating the type of the loaded optical disc. 2. The optical disc discriminating device according to claim 1, wherein the optical disc type signal for discriminating the type of the optical disc is an optical disc type signal for discriminating whether the loaded optical disc is a single-sided disc or a double-sided bonded disc. 3. An optical disc recording / reproducing apparatus or an optical disc discriminating apparatus in an optical disc reproducing apparatus having a front loading mechanism for loading an optical disc by sliding a disc tray, wherein the optical disc is placed on the opposite side of the optical head arrangement side. A disk surface reflectance measuring means for measuring the reflectance of the optical disk surface on the side opposite to the side where the optical head is arranged; and, when the optical disk is loaded, the disk surface reflectance measuring means slides the disk tray, A / D conversion that continuously measures the reflectivity of an optical disk and digitizes the change in the measured reflectivity, and a microscopic that analyzes the digitalized reflectivity distribution on the surface of the optical disk to determine the type of the loaded optical disk. An optical disc discriminator having a computer. 4. The optical disc according to claim 3, wherein the microcomputer analyzes the reflectance distribution on the surface of the digitized optical disc and determines whether the loaded optical disc is a single-sided disc or a double-sided disc. Discriminator.