CN1210704C - Device and method for layer jump control of CD player - Google Patents

Abstract

A layer jump control device and method are used to control the layer jump action of optical disk drive, the layer jump action includes kick-out action, hold action, brake action and wait action. The layer jump control device comprises a driver, an optical read-write head, a preamplifier, a controller and a low-pass filter, wherein the driver is used for outputting a driving control force; the optical read-write head is provided with an objective lens and a voice coil motor, and drives the voice coil motor according to the driving control force so as to vertically move the objective lens; the pre-amplifier is used for generating a focus error signal and transmitting the focus error signal to the controller to generate a focus control signal; the focus control signal is received through a low pass filter to generate a layer distance balance signal. When the optical disk drive does not jump layer, the drive control force is determined by the focusing control signal; when the optical disk drive performs a layer jump operation, the kick-out operation, the hold operation, the brake operation and the driving control force for performing the waiting operation in the layer jump operation are determined by the layer distance balance signal, the kick-out signal and the brake signal.

Description

Device and method for layer jump control of CD player

Technical field

The invention relates to a layer-jumping control device, which is used to control a CD player to perform layer-jumping action, and in particular relates to a device and method for controlling the layer-jumping action of a DVD CD player.

Generally speaking, optical discs can be divided into single-sided single-layer optical discs, such as CD/VCD discs, and single-sided double-layer or double-sided double-layer optical discs, such as DVD discs, according to their pressed storage surfaces and layers. piece. When reading a double-layer DVD disc, the read-write head of the optical disc drive must move the laser light spot between the two layers; therefore, the laser light spot must leave the original layer and reach the target layer.

1a-1c are schematic diagrams showing an optical read-write head, wherein the optical read-write head has an objective lens 210 and a voice coil motor 220, and the voice coil motor 220 is driven according to a driving control force, so that the objective lens 210 moves in the vertical direction . In Figure 1a, the objective lens 210 is in a natural equilibrium position B (indicated by a solid line); and the objective lens 210 can be moved to the L0 position in Figure 1b (indicated by a dotted line), at which point the optical head can focus the laser spot On the 0th layer of the disk; or the objective lens 210 can be moved to the L1 position in FIG. It can be seen from Figure 1b and Figure 1c that the distance between the L0 position and the natural balance position B is Do, the distance between the L1 position and the natural balance position B is D1, and the sum of the two is D=(Do+D1) is the disk layer spacing.

The purpose of the layer jumping action is to make the laser spot leave the original layer and reach the target layer. For example, as shown in FIG. 1b and FIG. 1c , the optical read/write head can jump layer from the L0 position to the L1 position. Generally speaking, the control force involved in the layer-jumping action can be divided into three parts: the control force of the optical read-write head from the natural equilibrium position to the original layer, the kicking force exerted by the original layer, and the approach to the target layer. Applied braking force and other three parts. When the objective lens 210 of the optical pickup is at the L0 position, a control force must be used to prevent it from returning to the natural equilibrium position B. When the optical disk drive intends to perform layer jumping, the objective lens 210 must first leave the L0 position, and make it leave the L0 position by kicking force to reach the linear control area of the L1 position. After leaving the L0 position, since the objective lens 210 still continues to move toward the L1 position, a braking force must be applied to slow down its speed, so that the control system can enter the linear control area, and finally reach the L1 position to complete the layer jumping action.

However, the above existing layer jump control method has its problems. First of all, the focus-controllable linear area of a double-layer disc, such as a DVD disc, is generally only ±1 μm, but the distance between two layers of a double-layer DVD disc is allowed to be 55 ± 15 μm. In contrast, the linear area that can be controlled The range is small, but the amount of variation of the layer spacing of different discs is relatively large. Therefore, if each disc calculates its layer jump position from the natural balance point of the objective lens, and uses the same control force, kicking force and braking force to perform the same layer jumping action, it may cause jumping for some discs. Layer failure problem.

In addition, when pressing the disc or placing the disc in the optical disc drive, sometimes due to problems such as positioning or poor pressing of the disc itself, wobble occurs when the disc is rotated for reading, causing the The platter rocks up and down at its natural equilibrium point relative to the objective lens. Therefore, when the layer jumping operation is performed, the driving control force may fluctuate, affecting the stability of the layer jumping, and it is easy to fail the layer jumping.

Contents of the invention

The object of the present invention is to provide a layer-jump control device, which can reduce the possibility of layer-jump failure caused by the above-mentioned disc layer spacing variation or surface vibration, so that the layer-jump action can be carried out stably, and solve the problem of double-layer disc layer jump. The problem.

The object of the present invention is achieved by providing a layer-jump control device for controlling the layer-jump action of an optical disc player, wherein the layer-jump action includes a kicking action, a holding action, a braking action, and a Waiting action, the layer jump control device includes: an optical read-write head with an objective lens and a voice coil motor, the optical read-write head drives the voice coil motor to vertically move the objective lens according to a driving control force; a preamplifier , used to generate a focus error signal; a controller, used to receive the focus error signal, and generate a focus control signal; a low-pass filter, used to receive the focus control signal, and generate a layer pitch balance signal; and a driver for outputting the driving control force; wherein when the optical disc player is not performing a layer-jumping action, the drive receives the focus control signal to determine the driving control force; on the other hand, when the optical disc player is performing a layer-jumping action During the kicking action, the driver receives a kicking signal and the layer distance balance signal and determines the driving control force, and when performing the braking action, the driver receives a braking signal and the layer distance balance signal to determine the driving force When performing the holding action and the waiting action, the driver receives the layer distance balance signal to determine the driving control force.

In the above-mentioned layer jump control device, the optical disc drive can be a DVD optical disc drive, and the controller can be an equalizer. Also, the layer distance balance signal can be the DC potential of the focus control signal.

The present invention also provides a method for controlling an optical disc drive to perform layer jumping, wherein the optical disc drive includes a vertically movable optical read-write head, a pre-amplifier, a controller, and a low-pass filter, the method The method includes the following steps: receiving a focus error signal generated by the preamplifier to the controller to generate a focus control signal; sending the focus control signal to the low-pass filter to generate a layer distance balance signal; A kicking action is performed according to the layer distance balance signal; a holding action is performed according to the layer distance balance signal; a braking action is performed according to a brake signal and the layer distance balance signal; and a braking action is performed according to the layer distance balance signal Perform a waiting action.

In the above method, the optical disc drive can be a DVD optical disc drive, and the controller can be an equalizer. Also, the layer distance balance signal can be the DC potential of the focus control signal.

The advantage of the present invention is that the floor distance balance signal generated by the low-pass filter can be used to indicate the natural balance position when the floor jump starts, thereby adding the floor distance balance signal to the kick signal and brake signal in the floor jump action , so that the layer jump action will not be affected by the variation of the disc layer spacing, or the layer jump will fail due to the generation of surface vibration. In this way, the layer-jumping action can be easily controlled, and the possibility of layer-jumping failure can be reduced.

Description of drawings

1a to 1c are respectively schematic diagrams of existing optical read/write heads;

Fig. 2 is the block diagram of layer jump control device of the present invention;

3 is a schematic diagram of a focus error signal and a focus control signal of a layer jumping action;

FIG. 4 is a flow chart of the layer-jumping operation of the optical disc drive.

Detailed ways

The layer jump control device of the present invention can be described by the embodiment shown in FIG. 2 . The layer-jump control device 10 in FIG. 2 is used to control the layer-jump action of an optical disc player, such as a DVD disc player, and the layer-jump action will be described later. The layer jump control device 10 has an optical read-write head 110 , a pre-amplifier (Pre-amp) 120 , a controller 130 , a low-pass filter 140 and a driver 150 . The structure of the optical read-write head 110 is similar to the existing optical read-write head shown in FIGS. A driving control force drives the voice coil motor 220 to vertically move the objective lens 115 . The pre-amplifier 120 generates a focusing error signal (Focusing Error Signal) according to the control result of the optical pickup 110 . The controller 130 can be an equalizer (Equalizer), which receives the focus error signal, processes it and generates a focus control signal. The low-pass filter 140 receives the focus control signal and generates a layer pitch balance signal, for example, converts the focus control signal into a DC potential. The driver 150 is used to output the driving control force to the optical head 110 .

In addition, FIG. 2 also includes a switch 160, which is used to control switching whether the layer-jumping action is performed or not. When the layer jump action is not performed, the switch 160 makes the focus control signal directly sent to the driver 150; if the layer jump action is performed, the switch 160 is connected to the low-pass filter 140, so that the layer distance balance signal sent out matches the kick signal or the brake signal and sent to the driver 150 . As shown in FIG. 2 , it is the state in which the layer jumping operation is in progress.

The above-mentioned layer-jump control device 10 is applicable to a DVD disc 50 with single-sided double-layer or double-sided double-layer, or any other type of double-layer storage medium that requires layer-jumping.

The floor jumping action performed by the floor jumping control device 10 of this embodiment can be divided into four stages, including a kicking action, a holding action, a braking action and a waiting action. These actions can be further explained with reference to FIG. 3 and FIG. 4 .

As shown in FIG. 3 , before layer jumping is performed, the focus error signal output by the pre-amplifier 120 maintains a certain value. At this time, the switch 160 is connected to the contact of the controller 130, and the focus control signal generated by the controller 130 controls the driver. The driving control force generated by 150 keeps the objective lens 115 at the original layer, that is, the laser spot remains at the original layer (for example, layer 0). Due to the layer spacing difference of the DVD disk itself and the possible surface vibration phenomenon, etc., the focus control signal may change continuously. At the same time, the layer distance balance signal generated by the focus control signal sent to the low-pass filter 140 is also constantly changing.

Please refer to Fig. 4, if switch 160 is input the instruction of a layer-jumping control signal, start to carry out layer-jumping action (step S10), this moment switch 160 is connected to the contact of low-pass filter 140 (as shown in Figure 3), by The low-pass filter 140 generates the layer distance balance signal (step S20), at this time the low-pass filter 140 can stop the action, so that the layer distance balance signal does not change and obtain a fixed value; then, the layer distance balance signal is sent to the adder , and cooperate with the addition of the kicking signal to generate the kicking action as shown in FIG. 3 , and send it to the driver 150 to perform the kicking action (step S30). From the check points F1 and F2 of the focus misfocus signal, it can be confirmed whether the laser spot is detached from the original layer.

Secondly, after the kicking action is completed, that is, after it is determined that the laser spot has departed from the 0th layer, the kicking signal is stopped, and the driver 150 is only controlled by the layer distance balance signal, and the holding action is carried out (step S40), so that the objective lens 115 continues to move to the target layer, that is, the laser spot continues to move to the target layer (that is, the first layer). The completion of the holding action can be checked by the brake check point F3 of the focus error signal in FIG. 3 .

Secondly, as shown in Figure 3, after the focus misfocus signal passes through F3, it means that the objective lens 115 of the optical read-write head 110 is close to the linear controllable range of the first layer, and the braking signal can be started, and the braking signal and the layer distance are balanced signal to control the driver 150 to perform a braking action (step S50) for a period of time.

After the braking action, it does not mean that the objective lens 115 must have completely entered the linear controllable range of the first layer. Therefore, in order to ensure that the layer jump focus control will not cause the layer jump to fail, the layer distance balance signal is used to control the waiting action (step S60). The completion of the waiting action can be checked by the brake check point F4 of the focus misfocus signal in FIG. 3 .

After the waiting is over, the switch 160 can switch back to the focus control signal to end the layer jumping operation (step S70 ), and at the same time, the low-pass filter 140 can continue to update the layer distance balance signal. At this point, the layer-jumping action from layer 0 to layer 1 is completed.

The above-mentioned layer jump control action is described by taking layer 0 to layer 1 as an example for illustration. When jumping back to the 0th floor from the 1st floor, the actions are the same, only need to reverse the kick signal and the brake signal to perform the same layer jumping action.

Although the present invention has been disclosed in conjunction with the above preferred embodiments, it is not intended to limit the present invention. Any skilled person in the art can still make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the present invention The scope of protection should be defined by the claims.

Claims (8)

1. a control device of floor skip moves in order to the skip floor of controlling a CD player, and wherein this skip floor moves and comprises that kicking out of action, keeps action, a brake to move and a wait action, and this control device of floor skip comprises:

One optical read/write head has object lens and a voice coil motor, and this optical read/write head drives voice coil motor with these object lens of vertical moving according to a drive controlling power;

One pre-amplifier is in order to produce a focus error signal;

One controller in order to receiving this focus error signal, and produces a focus control signal;

One low-pass filter in order to receiving this focus control signal, and produces a layer distance balancing signal; And

One driver is in order to export this drive controlling power;

Wherein when this CD player was not carried out the skip floor action, this driver received this focus control signal to determine this drive controlling power; When this that carries out skip floor action when this CD player kicked out of action on the other hand, this driver receives one and kicks out of signal and this layer distance balancing signal and determine this drive controlling power, and when carrying out this brake action, this driver reception one brake signal and this layer distance balancing signal are to determine this drive controlling power, and when carrying out this maintenance action and carrying out this wait action, this driver receives this layer distance balancing signal to determine this drive controlling power.

2. control device of floor skip as claimed in claim 1, wherein this CD player is a DVD CD player.

3. control device of floor skip as claimed in claim 1, wherein this controller is a balanced device.

4. control device of floor skip as claimed in claim 1, wherein this layer distance balancing signal is the DC potential of this focus control signal.

5. control one CD player is carried out the method that skip floor moves, and wherein this CD player comprises a vertically moving optical read/write head, a pre-amplifier, a controller and a low-pass filter, and this method comprises the following steps:

Receive a focus error signal that this pre-amplifier produces to this controller to produce a focus control signal;

Transmit this focus control signal to this low-pass filter to produce a layer distance balancing signal;

Kick out of signal and this layer distance balancing signal to carry out kicking out of action according to one;

Keep action according to this layer distance balancing signal to carry out one;

Move to carry out a brake according to a brake signal and this layer distance balancing signal; And

Wait for action according to this layer distance balancing signal to carry out one.

6. method as claimed in claim 5, wherein this CD player is a DVD CD player.

7. method as claimed in claim 5, wherein this controller is a balanced device.

8. method as claimed in claim 5, wherein this layer distance balancing signal is the DC potential of this focus control signal.

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