JPS6371941A - Optical disk reproducing device - Google Patents

Abstract

PURPOSE:To attain a compact size and a low cost by detecting the deflection angle of an optical disk by a pair of reflection type photosensors and adjusting a gate by a gate mechanism common to a disk motor rotating mechanism. CONSTITUTION:When there is a deflection in a video disk 21, a difference is produced in an output current since the distance to the detecting surfaces of the video disk 21 are respectively different. The respective output current is applied to a driving circuit 34 through a differential amplifier 33 and the gate mechanism 15 is driven so as to equalize the respective distances to the detecting surfaces of the respective reflection type photosensors 31, 32 and the video disk 21 and eliminate the difference in the output current and incline the disk motor 1 by theta in the direction shown by an arrow. Thereby, the reproducing surface of the video disk 21 is set in parallel to the guide system of an optical head 20, namely, an optical beam 40 can be emitted vertically to the reproducing surface of the video disk 21.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an optical disc device, and particularly to a compatible player in which optical discs of different shapes are controlled by the same device, the emission angle of a light beam to an optical disc can be changed with a simple configuration. can be corrected vertically. Regarding the tilt mechanism.

[Conventional technology]

In order to obtain a good reproduction signal in an optical disc device, it is necessary to emit a light beam perpendicularly to the optical disc.
In conventional devices, as described in Japanese Utility Model Application Publication No. 60-12829, the deflection angle of the optical disk is detected using a dedicated detector.
Accordingly, a method has been used in which the tilting angle of the optical head is adjusted using a tilting mechanism provided on the transfer table.

[Problem that the invention seeks to solve]

In the above conventional technology, a dedicated detector is required to detect the deflection angle of the optical disk, and the weight of the transfer unit increases due to the provision of a tilting mechanism on the transfer table, and the optical head is mounted using a linear motor etc. There has been a problem in that it is difficult to drive the transfer section and perform high-speed access.

An object of the present invention is to detect the deflection angle of an optical disc using an existing detector that detects the size of the optical disc in a compatible player capable of playing two types of optical discs with different sizes (for example, a compact disc and a video disc). The objective is to reduce the cost and to achieve high-speed access by reducing the weight of the transfer unit by adjusting the angle of incidence of the light beam onto the optical disk using a tilting mechanism provided outside the transfer table.

[Means for solving problems]

The above purpose is to provide a turntable section for compact disks and a turntable section for video disks at both ends of the spindle of a single disk motor, and rotate the disk motor 180 degrees depending on the type of optical disk to be played. In a compatible player that mounts an optical disc, a pair of reflective photosensors, which have been conventionally provided to detect the size of the loaded optical disc, also detects the deflection angle of the optical disc, and a base on which a disc motor, etc. is installed. This is achieved by adjusting the rotation angle of the disc motor using a tilting mechanism provided above to vertically correct the angle of the optical disc with respect to the light beam.

[For production]

The above-mentioned pair of reflective photosensors are installed parallel to the transport section guide system, which has an optical head mounted on the innermost and outermost peripheries of the mounted video disc, to detect the presence or absence and size of the optical disc. As will be described later, since the reflective photosensor can obtain an output current according to the distance to the detection section (lower surface of the optical disk), the outputs of the reflective photosensors on the inner and outer peripheries are compared to determine the distance to the optical disk surface. By adjusting the rotation angles of the disk motors so that the angles are equal to each other, the optical disk can be set parallel to the guide system, that is, the incident angle of the light beam can be corrected to be perpendicular to the optical disk. In addition, since the tilting mechanism is installed on the base, the weight of the transfer unit can be reduced and high-speed access is possible.Furthermore, many of the components of the tilting mechanism are the same as the disk motor rotation mechanism, which reduces costs. You can also aim for

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
3 to 3 are schematic configuration diagrams of a compatible player showing one embodiment of the present invention, and FIG. 1 shows a video disc 21.
FIG. 2 shows the state after the correction, and FIG. 3 shows the state with the compact disc 22 mounted with the disc motor 1 rotated 180 degrees. FIG. 4 is a diagram showing the relationship between the distance to the detection object of the reflective photosensor and the output current.
and a compact disc turntable section 4 are respectively fixed, and the disc motor 1 is fixed to both turntable sections 3,
It is rotatably held on a base 10 via a rotation shaft 5 that is equidistant from the optical disk support surface of No. 4 and provided perpendicular to the access direction of the optical head 20 . The disk motor 1 is driven 180 degrees around a rotation shaft 5 by a rotation mechanism (not shown) to drive an optical disk 21.2 to be played back.
The turntables 3 and 4 corresponding to 2 are positioned at predetermined locations, and the optical disks 21 and 22 are mounted by the gramper 6, and the first turntable whose tip is pressed into contact with the arm portion 7 that rotates integrally with the disk motor 1 is installed. Adjustment screw 11 or 2nd
The disc motor 1 is positioned using the adjusting screw 12. The first and second adjustment screws 11, 12 are both engaged with the base 10, and a gear 13 is fixed to the first adjustment screw 11 that presses against the arm portion 7 when playing the video disc 21. It is driven by a drive motor 14. Furthermore, second reflective photosensors 31 are provided at the innermost and outermost positions of the video disc 21, respectively.
and the second reflective photosensor 32 are installed so that the heights connecting them are parallel to the guide system (not shown) of the optical head 20, and when the optical disks 21 and 22 are not mounted, both reflective photosensors 32 Neither of the photosensors 3L and 32 outputs a signal; only the first reflective photosensor 31 outputs when the compact disc 22 is loaded, and both reflective photosensors 31 and 32 output when the video disc 21 is loaded. The presence or absence and type of optical discs 21 and 22 are detected.

First, the operation of the tilting mechanism 15 when playing back the video disc 21 will be explained using FIGS. 1 and 2.

FIG. 1 shows a state in which a video disk 21 is mounted and driven to rotate.The video disk 21 bends as shown in the figure due to the balance between its own weight and centrifugal force, and the optical head 21 bends as shown in the figure.
Since the light beam 40 emitted from the video disc 21 is not perpendicularly incident on the playback surface of the video disc 21, crosstalk occurs and adversely affects the playback signal. Here, since the output current of the reflective type sensor 31, 32 and the distance between the detection unit and the bottom surface of the optical disk have the relationship shown in FIG. 4, it can be used as a distance detector if the detection range is limited to the area indicated by the arrow in the figure. is possible. Therefore, when the video disk 21 is deflected as shown in FIG. 1, the distances from the reflective photosensors 31, 32 to the detection surface of the video disk 21 are different, resulting in a difference in output current. Therefore, as shown in FIG. 2, each output current is applied to the drive circuit 34 through the differential amplifier 33, so that the distances between each reflective photosensor 31, 32 and the detection surface of the video disk 21 are equalized, and the output currents differ. By driving the tilting mechanism 15 and tilting the disc motor 1 by an amount O in the direction shown by arrow A in the figure, the playback surface of the video disc 21 is made parallel to the guide system of the optical head 2o, that is, the light beam 40 can be emitted perpendicularly to the playback surface of the video disc 21.

Next, the case of reproducing the compact disc 22 will be explained with reference to FIG.

3 shows a state in which the disc motor 1 is rotated 180 degrees by the rotation mechanism to replace the turntable part, and a compact disc 22 is mounted by the clamper 6, compared to the state shown in FIGS. 1 and 2. show. Generally, the compact disc 22 is smaller than the video disc 21 (1/2.5 in diameter).

Since it is lightweight (weight 1/10), deflection due to its own weight is hardly a problem. Therefore, in the configuration shown in FIG. Once done, there is no need to make any further adjustments. However, as a matter of course, the adjusting screw 12 is also provided with a driving means, and a third reflective type sensor (not shown) is provided on the outermost periphery of the compact disc 22, so that the adjustment screw 12 can be tilted in the same way as in the case of the video disc 21 described above. It does not matter if the angle is controlled.

Further, the tilting mechanism according to the present invention can be realized not only in a compatible player but also in a normal optical disc player by providing a rotating mechanism for the disc motor 1 and a pair of reflective photosensors 31 and 32.

〔Effect of the invention〕

According to the present invention, a compact disc turntable section and a video disc turntable section are provided at both ends of the spindle of a single disc motor, and the disc motor is rotated 180 degrees depending on the type of optical disc to be played. In a compatible player that mounts a desired optical disc, a pair of reflective photosensors, which have been conventionally provided to detect the size of the mounted optical disc, also detects the deflection angle of the optical disc, and detects the deflection angle of the optical disc. By adjusting the tilting mechanism using the tilting mechanism, which is often the same as the disk motor rotation mechanism, the tilting mechanism can be configured at a low cost, and the lightweight transfer section facilitates high-speed access, making it compact and low cost. This enables us to provide high-performance optical disc devices.

[Brief explanation of the drawing]

1 to 3 are schematic configuration diagrams of a compatible player according to an embodiment of the present invention, and FIG. 4 is a graph showing the relationship between the output current of a reflective photosensor and the distance to a detection object. DESCRIPTION OF SYMBOLS 1... Disk motor, 2... Rotating shaft, 10... Base, 15... Tilt mechanism, 20... Optical head. Akira I, second figure,

Claims (1)

[Claims] 1. A single disc motor, a pair of turntable parts with different diameters provided at both ends of the spindle of the disc motor, and a rotating shaft provided at a position equidistant from the disc support surface of the pair of turntables. , a rotation mechanism that rotates the disk motor 180 degrees around the rotation axis, and a pair of turntable sections each positioned at a predetermined position, and two types of center holes with different diameters depending on the optical head. In a compatible player for playing back an optical disc, a pair of adjustment screws are provided which are in pressure contact with a part of the disc motor rotated by the rotation mechanism to position the disc motor, and the pair of adjustment screws adjust the diameter. When playing a large optical disc, one of the adjusting screws that is in pressure contact with the disc motor is provided with a driving means for moving the adjusting screw, and the driving means is operated by the output of a detector that detects the tilt angle of the optical disc. An optical disc reproducing apparatus characterized in that the optical disc is vertically irradiated with a light beam from the optical head by moving the adjusting screw and changing the mounting angle of the disc motor.