JPH11250467A - Method and device for layer jump in dual layer optical disk drive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform effective layer-jumps at the time of performing a dual layer jump by impressing a first kick pulse on a focus driver at the time of performing a jump from a low-order layer to a high-order layer and impressing a second kick pulse whose value is smaller than that of the first kick pulse on the focus driver at the time of performing a jump from the high-order layer to the low-order layer. SOLUTION: The first differentiator 56 of a kick pulse generating circuit 53 is constituted of a resistor R1 and a capcitor C2 and the second differentiator 90 of the circuit is constituted of a resistor R2 and a capacitor C2 and when values of the resistors R1, R2 are assumed to be the same, the value of the capacitor C1 is made larger than that of the capacitor C2. As a result, the value of a kick pulse (at the time of perfrom the jump from the lower order layer to the high-order) to be generated by the first differentiator 56 of the kick pulse generating circuit 53 is larger than the value of a kick pulse (at the time of performing the jump from the high-order layer to the low-order layer) to be generated by the second differentiator 90. The value of the differentiator 90 is decided by considering the force due to the gravity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk drive servo system, and more particularly to a method and an apparatus for layer jumping in a drive of a dual layer optical disk.

[0002]

2. Description of the Related Art A compact disk, that is, a CD is a CD-DA (digital-A) for recording pure music.
audio) is common, but due to the huge storage capacity,
It is also widely used as an auxiliary recording device for recording video, text or computer data. Such a CD recording / reproducing medium used for recording / reproducing data is called a CD family. The most representative CD families are CD-ROM, C
DI (interactive), photo CD, video CD, map CD (used for automobile navigation equipment), and the like.

On the other hand, DVD (Digital Video)
o Disc or DigitalVersatile
Disc) has become synonymous with high-quality and high-quality information transmission media. With the realization of DVD, it has become an era where broadcast-level high-quality images can be reproduced and powerful images can be enjoyed on a large screen. Applied devices of DVD include DVD video player, DVD audio player, DVD
There is a ROM drive and the like. Table 1 below shows DVD discs
There are several types such as

[0004]

[Table 1]

[0005] In Table 1, the capacity of each DVD disc type is based on a 12 cm disc. The purpose of producing a DVD disc in dual layer is to increase the capacity of the disc,
When made in dual layer, as shown in Table 1, 1
It can be increased to 7 GB. FIG. 1 shows an example of a dual-layer disc structure, in which LYR0 is a first layer and LYR1 is a second layer. The first layer LYR0 is a dielectric semi-transparent film, and the second layer LYR1 is a reflective film.

When one pickup is used, an advantage of a dual-layer disc as shown in FIG. 1 as compared with a dual-side disc is that the disc does not have to be turned over during reproduction. As shown in FIG. 2, the second layer LYR1 of the dual layer disc adopts a two-track path method. In FIG.
The second layer LYR1 is opposite to the parallel track path system which proceeds from the inner circumference to the outer circumference in the direction like the first layer LYR0 as shown in FIG. 5A, and is opposite to the first layer LYR0 as shown in FIG. In the direction, an opposite track path system is adopted, which proceeds from the outer periphery to the inner periphery. When playing back a movie disc manufactured by the opposite track path method (b), after playing all the way to the outer periphery of the first layer LYR0, it instantaneously jumps to the second layer LYR1 and continues playing the movie from the outer periphery. The advantage is that the movie can be played continuously even in a layer transition situation.

Thus, when using a dual layer disc, a dual layer jump is provided. The dual layer jump takes several ms from the layer that is currently focused on.
This is the action to quickly shift the focus to another layer within.

FIG. 3 shows a moving direction of a lens and a focus error signal waveform when jumping from the layer LYR0 to the layer LYR1 of the dual layer disc. In FIG. 3, a waveform FE indicates a focus error signal when jumping from the first layer LYR0 to the second layer LYR1. Until the focus error signal FE is before the falling pulse, the lens is layer L
In a state where YR0 is focused on, the F
After the point at which the rising pulse appearing after E is zero crossed, the layer 1 is focused on.

The intermediate state is between the layers LYR0 to L
It is in a state of jumping to YR1. On the other hand, the waveform of the focus error signal FE when moving from the second layer LYR1 to the first layer LYR0 has an opposite phase to the waveform of the focus error signal FE shown in FIG.

At present, the pure time required for the layer jump is 5 ms on average, for example, assuming that the digital servo processor chip for DVD, TC9420F, is used.
Including the time required for focusing and tracking stabilization (25 ms), the time required for the layer jump is about 30 ms.

On the other hand, among the CD-related equipment widely used at present, there is a digital servo processor chip for CD such as TC9440F.
4440F cannot be used as a digital servo processor for DVD because it has no control function such as layer jump. That is, the biggest difference between the digital servo processor for CD and the digital servo processor for DVD is
Whether or not there is a layer jump function. Therefore, if the layer jump function can be performed using a digital servo processor chip for CD such as TC9440F, the DVD servo related control can be performed not only by the digital servo processor chip for DVD but also by the digital servo processor chip for CD. Will.

Japanese Patent Application No. 1997-78202, which was filed in Korea in advance by the present applicant, discloses a technique having a layer jump function using a digital servo processor chip for CD. In the layer jump function using the digital servo processor chip for CD or the layer jump function using the digital servo processor chip for DVD disclosed in this patent application, as shown in FIG.
Kick when moving like 0 → LYR1 and LYR
The kick at the time of moving like 1 → LYR0 is applied with the same value.

When moving from LYR0 to LYR1 and LYR1
→ When moving LYR0, the weight of the pickup is always the same, but the pickup moves from LYR1 to LY
When descending to R0, kick due to gravity, LY
It falls at a faster speed than when rising from R0 to LYR1. Therefore, the conventional layer jump method in which a kick is applied with the same value may not be able to perform focusing at the time of layer jump correctly.

[0014]

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a method and apparatus for performing an effective layer jump in a dual layer jump.

[0015]

To achieve the above object, the present invention relates to a method for jumping between layers in a dual-layer optical disk drive having a focus driver, comprising the steps of jumping from a lower layer to an upper layer of the dual layer. Applying a kick pulse of a first magnitude to the focus driver and a second magnitude smaller than the value of the kick pulse of the first magnitude when jumping from an upper layer to a lower layer of the dual layer. Applying a kick pulse to the focus driver.

The present invention also relates to an apparatus for jumping between layers in a dual-layer optical disk drive.
A focus driver driven by predetermined control, a control unit for controlling the inter-layer jump, and a jump control from a lower layer to an upper level of the control unit to differentiate a first level voltage by a first time constant, A first differentiator for applying a first kick pulse to the focus driver; and a jump control from an upper layer to a lower layer of the control unit to differentiate a second-level voltage by a second time constant value, and And a second differentiator for applying a second kick pulse.

[0017]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In the drawing,
The same components are denoted by the same reference numerals in all figures. In addition, a detailed description of known functions and configurations that may unnecessarily obscure the gist of the present invention will be omitted. FIG. 6 is a circuit configuration diagram for a layer jump according to an embodiment of the present invention.

In the embodiment of the present invention, before describing the circuit configuration for the layer jump shown in FIG. 6, in order to help understand the description of the present invention, Japanese Patent Application No. 1997-78202 filed by the present applicant. The operation of the layer jump will be briefly described with reference to FIG. 4 which is a layer jump circuit disclosed in US Pat.

FIG. 4 is a circuit diagram for a dual layer jump using the TC9440F which is an example of a digital servo processor for a CD. The microcomputer 52, the digital servo processor 50 for a CD, and the kick pulse generating circuit 5
3. It comprises a layer jump break control circuit 64 and a selection circuit 57. The microcomputer 52 is used for system control, and receives a focus error signal FE detected from a pickup of the drive as an input, and outputs terminals TEST100 and TEST10 for jumping between layers.
1, 100, and the output terminals TEST100, TE
It outputs COMMAND and first, second, and third layer jump control signals for jumping between layers through ST101 and ST100 and an instruction terminal.

The digital servo processor 50 for CD is provided with an instruction CO from the microcomputer 52 for jumping between layers.
Initialization for jumping between layers is performed based on MMAND, and the detected focus error signal FE is detected.
, A focus error correction signal for focus error correction is output from the FOO end. The kick pulse generating circuit 53 is connected to an output terminal TEST100 of the microcomputer 52.
And a kick pulse for an inter-layer jump is generated by differentiating a voltage level due to the input of the first and second layer jump control signals output through the TEST 101.
Output to the focus drive.

Layer jump break control circuit 64
Performs a predetermined control operation with a third layer jump control signal output through an output terminal 100 of the microcomputer 52 and an applied focus error signal FE as inputs, and outputs a break pulse required for an inter-layer jump to the focus level. The error signal FE is generated immediately before the focus-on point at which zero crossing is performed, and is output to the focus driver. Then, the selection unit 57
The first and second jump control so that the focus error correction signal output from the FOO terminal of the D digital servo processor 50 is output to the focus driver after the focus on point at which the focus error signal is zero-crossed. The focus error correction signal is selected and output based on the logic state of the signal.

FIG. 5 is a timing chart of an example related to a dual layer jump using the TC9440F which is an example of the CD digital servo processor 50 of FIG. The timing diagram shown in FIG.
FIG. 4 is a timing chart when jumping to YR1 (shown in FIG. 3).

Referring to FIGS. 4 and 5, the operation of generating a kick pulse at the time of a layer jump will be described more specifically. The microcomputer 52 shown in FIG.
At the rising edge of the pulse, the binary logic "L" state (first layer jump control signal) is maintained and output through the TEST100 terminal (not shown in FIG. 5), and the binary logic "L" state (the (See FIG. 5).

As a result, the NPN transistor 54 of the kick pulse generating circuit 53 is turned off, and the PNP transistor 55 is turned on. As a result, the 2Vref voltage at the collector end of the PNP transistor 55 becomes the node 86
, And the output A from the node 86 transitions from Vref to 2Vref as shown in FIG. 2V
The output A of the ref level is differentiated by a differentiator 56 and B
It looks like the first pulse of the signal.

On the other hand, when the first and second layer jump control signals are all output as the binary logic "L" through the TEST100 and TEST101 terminals of the microcomputer 52, the binary logic "L" which is the output of the TEST100 becomes the inverter. After being inverted at 58, the state becomes “H” and is applied to one end of the AND gate 60, and the binary logic “L” output from the TEST 101 is immediately applied to the other end of the AND gate 60. Therefore, the output of the AND gate 60 becomes logic "L". Thus, the multiplexer 62 outputs Vr
Select the XO input terminal to which ef is applied.

As a result, TEST100 and TEST1
In the section in which the outputs of the 01 terminals are all binary logic "L", the FOO of the digital servo processor 50 for CD is used.
Output through the terminal and integrated by the integrator 61
The signal is not output to the focus drive. Therefore, the first pulse of the B signal output from the differentiator 56 of the kick pulse generation circuit 53 is applied to the focus driver as a kick pulse. The kick pulse of the K signal applied to the focus driver is applied to the focus driver, and finally the pickup is driven by the layer LY shown in FIG.
A kick is made from R0 to LYR1.

On the other hand, when a kick is performed from the layer LYR1 to the layer LYR0, a transition is made from the TEST100 terminal of the microcomputer 52 to binary logic "H" and output, and the binary logic "H" is outputted from the TEST101 terminal of the microcomputer 52. It is maintained and output.

Hereinafter, a circuit configuration and operation for a layer jump according to an embodiment of the present invention will be described with reference to FIG. In the embodiment of the present invention, in order to perform an effective layer jump at the time of the dual layer jump, when jumping from LYR0 to LYR1 shown in FIG.
When a kick pulse having a first magnitude is applied to the focus driver to jump from layer LYR1 to LYR0, a kick pulse having a second magnitude at least smaller than the value of the kick pulse having the first magnitude is applied to the focus driver. To be applied. Therefore, the first differentiator 56 is connected to the emitter terminal of the PNP transistor 55 connected to the TEST101 terminal of the microcomputer 52, and the second differentiator is connected to the collector terminal of the NPN transistor 54 connected to the TEST100 terminal of the microcomputer 52. 90 are connected.

The output line of the first differentiator 56 is connected to a focus driver through a resistor R3, and the output line of the second differentiator 90 is connected to the focus driver through a resistor R4. The first differentiator 56 includes a resistor R1 and a capacitor C1, the second differentiator 90 includes a resistor R2 and a capacitor C2, and a resistance R1 of the first differentiator 56 and the second differentiator 90. , R2 are the same, the value of the capacitor C1 of the first differentiator 56 is larger than the value of the capacitor C2 of the second differentiator 90 (C1> C2).

Therefore, the kick pulse value (LYR) generated from the first differentiator 56 of the kick pulse generation circuit 53
(When jumping from 1 to LYR0) is greater than the kick pulse value (when jumping from LYR1 to LYR0) generated from the second differentiator 90. The value of the kick pulse of the differentiator 90 of the second magnitude may determine the value of the capacitor C2 relative to the value of C1 in consideration of the force generated by gravity.

When jumping from the layer LYR0 to the layer LYR1, the terminal TEST100 of the microcomputer 52 is continuously
The binary logic “L” state is maintained, and the TEST 101 terminal is changed from the binary logic “H” state to the “L” state. As a result, the PNP transistor 55 connected to the TEST 101 terminal is turned on, and a voltage level transitioned from Vref to 2 Vref is applied to the first differentiator 56. Since the first differentiator 56 is set to have a higher RC time constant value than the second differentiator 90, the first differentiator 56 differentiates and forms a kick pulse larger than the kick pulse formed by the second differentiator 90, and sends the differentiated kick pulse to the focus driver side. Apply.

On the other hand, when jumping from the layer LYR1 to LYR0, a transition is made from the binary logic "L" state to the "H" state from the TEST100 terminal of the microcomputer 52, and the binary logic "H" is output from the TEST101 terminal of the microcomputer 52. "Continuously maintained and output. This allows TE
NPN transistor 54 connected to ST100 terminal
Is conducted, and the second differentiator 90 supplies 0 (g) from Vref.
A voltage level value transitioned to a (round) value is applied. The second differentiator 90 has a lower RC than the first differentiator 56.
Since the time constant value is set, the kick pulse smaller than the kick pulse formed by the first differentiator 56 is differentiated and formed, and is applied to the focus driver side.

Although the present invention has been described with reference to specific embodiments of the present invention, various modifications can be made without departing from the scope of the present invention. Therefore, the scope of the present invention should not be determined by the above-described embodiments, but should be determined by the appended claims and equivalents thereof.

[0034]

As described above, according to the present invention, when jumping from a lower layer to an upper layer, when jumping from a lower layer to a lower layer, the kick pulse value (power) is made different. Effective and effective layer jump.

[Brief description of the drawings]

FIG. 1 is a diagram showing a structure of a dual layer disc.

FIG. 2 is a diagram showing a dual-layer track path.

FIG. 3 Layer LYR of a dual layer disc
FIG. 9 is a diagram illustrating a moving direction of a lens and a focus error signal waveform when jumping from 0 to LYR1.

FIG. 4 is a Patent Application No. 199 filed by the present applicant in advance.
FIG. 2 is a circuit configuration diagram for a layer jump presented in No. 7-78202.

FIG. 5 is a signal timing diagram for a layer jump according to FIG. 4;

FIG. 6 is a circuit configuration diagram for a layer jump according to an embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 50 Digital servo processor for CD 52 Microcomputer 53 Kick pulse generation circuit 54 NPN transistor 55 PNP transistor 56 First differentiator 57 Selection circuit 58 Inverter 60 AND gate 61 Integrator 62 Multiplexer 64 Layer jump break control circuit 70 Differentiator 73 Integrator Device 74 exclusive OR gate 76 NPN transistor 78 NPN transistor 80 exclusive OR gate 82 NPN transistor 84 inverting amplifier 86 node 90 second differentiator

Claims (6)

[Claims] 1. A method for jumping between layers in a dual-layer optical disk drive having a focus driver, wherein a kick pulse having a first magnitude value is supplied to the focus driver when jumping from a lower layer to an upper layer of the dual layer. Applying a kick pulse of a second magnitude smaller than the value of the kick pulse of the first magnitude to the focus driver when jumping from an upper layer to a lower layer of the dual layer. A method comprising: 2. The kick pulse value of the second magnitude is:
2. The method according to claim 1, wherein the value of the kick pulse having the first magnitude is set in consideration of a value generated by gravity. 3. An apparatus for jumping between layers in a dual-layer optical disk drive, wherein: a focus driver driven by a predetermined control to focus on the layer; a control unit controlling the jump between layers; By jump control from the lower layer to the upper level of the section, the voltage of the first level is differentiated by the first time constant,
A first differentiator for applying a first kick pulse to the focus driver; and a jump control from an upper layer to a lower layer of the control unit to differentiate a second-level voltage by a second time constant value, and And a second differentiator for applying a second kick pulse. 4. The apparatus according to claim 3, wherein the magnitude of the second kick pulse is smaller than the magnitude of the first kick pulse by a magnitude corresponding to gravity. 5. The apparatus according to claim 3, wherein the first differentiator and the second differentiator comprise a capacitor and a resistor. 6. The capacitance of the first differentiator is greater than the capacitance of the second differentiator, assuming that the first and second differentiators have the same resistance. Item 6. The apparatus according to Item 5.