KR100290958B1 - Method and apparatus for jumpping layer in drive using dual layers optical disk - Google Patents

Abstract

PURPOSE: A device for layer jump in a drive of a dual layer optical disk is provided to differentiate a value of a kick pulse when a lower layer jumps to an upper layer or when an upper layer jumps to a lower layer, thus efficiently performing the layer jump. CONSTITUTION: A focus drive is driven by a predetermined control to adjust a focus of a layer. A micro computer(52) controls jumping operations between layers. The first differentiator(56) differentiates a voltage of the first level by the first time constant value by a jump control to an upper layer from a lower layer, and applies the differentiated voltage to the focus drive as the first kick pulse. The second differentiator(90) differentiates a voltage of the second level by the second time constant value by a jump control to a lower layer from an upper layer, and applies the differentiated voltage to the focus drive as the second kick pulse.

Description

A device for layer jump in a drive of a dual-layer optical disc {METHOD AND APPARATUS FOR JUMPPING LAYER IN DRIVE USING DUAL LAYERS OPTICAL DISK}

The present invention relates to an optical disc drive servo system, and more particularly, to an apparatus for layer jump in a drive of a dual layer optical disc.

Compact discs, or CDs, are generally used as CD-DA (Digital Audio) for recording pure music, but are widely used as auxiliary recording devices for recording images, text, or computer data because of their large recording capacity. The CD recording and reproducing medium used for recording and reproducing data as described above is called a CD family. The most representative CD families are CD-ROM, CD-I (Interactive), Photo CD, Video CD, Map CD (used in car navigation system).

On the other hand, DVD (Digital Video Disc, or Digital Versatile Disc) has become synonymous with information transmission medium of high quality and high sound quality. With the realization of DVD, high-definition video at the broadcast level can be played back, and it is the era of enjoying powerful video on a large screen. Applications of DVD include DVD video players, DVD audio players, and DVD ROM drives. There are several kinds of DVD discs as shown in Table 1 below.

Disc type Capacity (12 cm discs) Single Side / Single Layer 4.7 GB (Giga Byte) Single Side / Dual Layer 8.5 GB Dual Side / Single Layer 9.4 GB Dual Side / Dual Layer 17 GB

In Table 1, the capacity of each DVD disc is based on a 12cm disc. The purpose of producing a DVD disc in dual layer is to increase the capacity of the disc. When creating a dual side / dual layer, it can be increased to 17 GB as shown in Table 1. have. Figure 1 shows an example of a dual layer disk structure, where LYR 0 is the first layer and LYR 1 is the second layer. The first layer LYR 0 is the dielectric translucent film and the second layer LYR 1 is the reflective film.

When using a single pickup, the advantage of a dual layer disc as shown in FIG. 1 over a dual side disc is that the disc does not have to be flipped during playback. The second layer LYR 1 of the dual layer disc has two track path schemes as shown in FIG. Referring to FIG. 2, the second layer LYR 1 has a parallel track path system that runs from the inner circumference to the outer circumference in the same direction as the first layer LYR 0 as shown in (a), and from the outside opposite to the first layer LYR 0. It takes the opposite track path that goes inwards. When playing a movie disc produced by the opposite track path method (b), the player can play all the movies up to the outer layer of the first layer LYR 0, and then jump to the second layer LYR 1 to play the movie continuously from the outer layer. The advantage is that the movie can be played seamlessly even in the transition situation.

As such, when using a dual-layer disc, there is a dual layer jump. Dual-layer jumps move the focus quickly to other layers within a few milli-seconds of the current focus on layer.

FIG. 3 shows the movement direction and the focus error signal waveform of the lens when jumping from the layer LYR 0 to LYR 1 of the dual layer disk. In FIG. 3, the waveform FE shows a focus error signal when jumping from the first layer LYR O to the second layer LYR 1. The state until the focus error signal FE is before the falling pulse is the state in which the lens is focused on the layer LYR 0, and the point in time after the rising pulse in which the FE is displayed is zero-crossed is the focus on state in the layer LYR 1. The state in the middle is jumping from layer LYR 0 to LYR 1. On the other hand, the waveform of the focus error signal FE when moving from the second layer LYR 1 to the first layer LYR 0 is opposite in phase with the waveform of the focus error signal FE shown in FIG.

The current time required to jump the layer is, for example, an average of 5ms for the TC9420F, a digital servo processor chip for DVD, and the time required for the rare jump including the time required to stabilize focusing and tracking (25ms) afterwards It is about 30ms.

On the other hand, currently widely used CD-related devices include, for example, TC9440F as a CD digital servo processor chip, but the chip TC94440F cannot be used as a digital servo processor for DVD because it does not have a control function such as layer jump. In other words, the biggest difference between the digital servo processor for CD and the digital servo processor for DVD is the difference of the layer jump function. Therefore, if the CD jumper can perform the layer jump function using a digital servo processor chip such as the TC9440F, the DVD servo-related control can be performed not only with the DVD digital servo processor chip but also with the CD digital servo processor chip.

Patent No. 1997-78202 previously filed by the present applicant discloses a technique for performing a rare jump function using a digital servoprocessor chip for CD.

In the ray jump function using the digital servoprocessor chip for CD or the layer jump function using the digital servoprocessor chip for DVD disclosed in the aforementioned patent application No. 1997-78202, the pickup is selected from the layer LYR 0 → LYR 1 as shown in FIG. This applies the same kick to the move and LYR 1 → LYR 0 to the same value. When LYR 0 → LYR 1 travels and LYR 1 → LYR 0 travels, the weight of the pickup is always the same, but if the pickup descends from LYR 1 to LYR 0 by the kick, the speed when the lift goes from LYR 0 to LYR 1 by the kick due to gravity Falls faster than Therefore, the conventional layer jump method that applies the kick to the same value may not properly perform focusing during layer jump.

Accordingly, an object of the present invention is to provide an apparatus for performing an effective layer jump during a dual layer jump.

According to the above object, the present invention is a device for performing inter-layer jump in a dual-layer optical disk drive, the focus driver is driven to focus on the information storage layer, a control unit for controlling the inter-layer jump, A first differentiator for differentiating a voltage of a first level into a first time constant value by a jump control from a lower layer to an upper layer of the controller and applying the first kick pulse to the focus driver; and a lower layer in an upper layer of the controller. The second differentiator may be configured to differentiate the voltage of the second level into the second time constant value by the low jump control and apply the second kick pulse to the focus drive as a second kick pulse.

1 is a view showing the structure of a dual layer disk,

2 shows a track path in a dual layer,

3 is a view showing a moving direction and a focus error signal waveform of a lens to jump from layer LYR 0 to LYR 1 of a dual layer disk;

4 is a circuit diagram for layer jump disclosed in Patent No. 1997-78202 filed by the applicant of the present application;

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

Figure 6 is a circuit diagram for a layer jump in accordance with an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the same elements in the figures are denoted by the same numerals wherever possible. In addition, detailed descriptions of well-known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

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

In the embodiment of the present invention, prior to describing the circuit configuration for the layer jump shown in FIG. 6, the layer jump circuit disclosed in the patent application No. 1997-78202 filed by the applicant for the purpose of understanding the description of the present invention. The operation of the layer jump will be briefly described with reference to Fig. 5 and Fig. 5 and its signal timing diagram. 4 is a circuit configuration diagram for dual layer jump using TC94FF, which is an example of a digital servo processor for a CD, and includes a microcom 52, a digital servo processor 50 for a CD, a kick pulse generating circuit 53, a layer jump brake control circuit 64, and a selection. It consists of a circuit 57. The microcomputer 54 is for system control, and has output terminals TESTI0 0, TESTIO 1, and IO0 for performing inter-layer jump with input of the focus error signal FE detected from the pickup of the drive, and the output terminals TESTI0 0, TESTIO 1 Outputs the command COMMAND and the first, second, and third layer jump control signals for jumping between layers through the IO0 and the command terminal. The digital servo processor 50 for CD performs initialization for inter-layer jump based on the command COMMAND for inter-layer jump in the microcomputer 52, and focus error correction signal for focus error correction based on the detected focus error signal FE. Output to the FOO stage. The kick pulse generating circuit 53 generates a kick pulse for jumping between layers by differentiating the voltage levels according to the inputs of the first and second layer jump control signals output through the output terminals TESTIO 0 and TESTIO 1 of the microcomputer 52. Will output The layer jump brake control circuit 64 performs a predetermined control operation by inputting the third layer jump control signal output through the output terminal IOO of the microcomputer 52 and the applied focus error signal FE to focus the brake pulse required for the jump between layers. The error signal FE is generated just before the focus-on time point of zero crossing and output to the focus driver. The selector 57 controls the focus error correction signal output from the FOO terminal of the digital servo processor 50 for CD to be 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 selectively output based on a logic state.

5 is a timing diagram of an example related to a dual layer jump using TC94FF, which is an example of the digital servo processor 50 for CD of FIG. The timing diagram shown in FIG. 5 is a timing diagram when jumping from layer LYR 0 to LYR 1 (shown in FIG. 3).

4 and 5 will be described in more detail an operation of generating a kick pulse during the layer jump. The microcomputer 52 of FIG. 4 maintains and outputs the binary logic ″ L ″ state (first layer jump control signal) through the TESTIO 0 terminal at the first pulse rising edge of the COMMAND signal (shown in FIG. 5), and the TESTIO 1 terminal. Through the transition to the binary logic ″ L ″ state (second layer jump control signal) through the output (shown in Figure 5). As a result, the NPN transistor 54 of the kick pulse generating circuit 53 is not conducting, and the PNP transistor 55 is conducting. As a result, the 2Vref voltage of the collector terminal of the PNP type transistor 55 is applied to the node 86, and the output A at the node 86 transitions from Vref to 2Vref as shown in FIG. The output A of the 2Vref level is differentiated in the differentiator 56 to become the first pulse of the B signal. On the other hand, when both the first and second layer jump control signals are output through the logic logic ″ L ″ through the TESTIO 0 and TESTIO 1 terminals of the microcomputer 52, the binary logic ″ L ″, which is the output of TESTIO 0, is inverted in the inverter 58 and then ″ H ″ state is applied to one end of AND gate 60, and binary logic ″ L ″, which is an output of TESTIO 1, is immediately applied to the other end of AND gate 60. Therefore, the output of AND gate 61 becomes logical ″ L ″. Accordingly, multiplexer 62 selects the XO input terminal to which Vref is applied. As a result, the C signal integrated by the integrator 61 output through the FOO terminal of the digital servo processor 50 for CD is not output to the focus driver in the section where the outputs of the TESTIO 0 and TESTIO 1 terminals are both binary logic ″ L ″. Therefore, the first pulse of the B signal output from the differential 56 of the kick pulse generating circuit 53 is applied to the focus driver as the kick pulse. The kick pulse in the K signal applied to the focus driver is applied to the focus driver so that the pickup finally performs a kick from layer LYR 0 to LYR 1 shown in FIG.

On the other hand, when performing a kick from layer LYR 1 to LYR 0, binary logic ″ H ″ is outputted from the TESTIO 0 terminal of the microcom 52, and binary logic ″ H ″ is maintained from the TESTIO 1 terminal of the microcom 52. Is output.

Hereinafter, a circuit configuration and an operation for layer jump according to an embodiment of the present invention will be described with reference to FIG. 6. In an exemplary embodiment of the present invention, in order to perform an effective layer jump during a dual layer jump, when a jump from the layer LYR 0 to LYR 1 shown in FIG. In the case of jumping to LYR 0, a kick pulse having a second magnitude value smaller than the first magnitude value is applied to the focus driver. For this purpose, the first differentiator 56 is connected to the emitter terminal of the PNP transistor 55 connected to the TESTIO 1 terminal of the microcomputer 52, and the second differentiator 90 is connected to the collector terminal of the NPN transistor 54 connected to the TESTIO 0 terminal of the microcomputer 52. . The output line of the first differentiator 56 is connected to the focus driver through a resistor R3, and the output line of the second differentiator 56 is connected to the focus driver through a resistor R4. The first differentiator 56 is composed of a resistor R1 and a capacitor C1, and the second differentiator 90 is composed of a resistor R2 and a capacitor C2. It is assumed that the resistance values R1 and R2 of the first differentiator 56 and the second differentiator 90 are the same. In this case, the value of the capacitor C1 of the first differentiator 56 is greater than the value of the capacitor C2 of the second differentiator 90 (C1> C2). Therefore, the kick pulse value (when jumping from layer LYR 0 to LYR 1) generated in the first minute 56 of the kick pulse generating circuit 53 is less than the kick pulse value generated at second minute 90 (when jumping from LYR 1 to LYR 0). Bigger The kick pulse magnitude value of the second differentiator 90 may determine the capacitor C2 value relative to the capacitor C1 value in consideration of the force generated by gravity.

When jumping from layer LYR 0 to LYR 1, the TESTIO 0 terminal of the microcom 52 remains in binary logic ″ L ″, and the TESTIO 1 terminal transitions from binary logic ″ H ″ to ″ L ″. As a result, the PNP transistor 55 connected to the terminal 1 of TESTIO is turned on, and a voltage level value transitioned from Vref to 2Vref is applied to the first differentiator 56. Since the first mill 56 is set to a higher RC time constant than the second mill 90, it is made by differentiating a kick pulse larger than the kick pulse made in the second mill 90 and applied to the focus driver.

On the other hand, when jumping from layer LYR 1 to LYR 0, binary logic ″ L ″ is transitioned to ″ H ″ from the TESTIO 0 terminal of the microcom 52, and binary logic ″ H ″ continues from the TESTIO 1 terminal of the microcom 52. It is maintained and output. As a result, the NPN transistor 54 connected to the TESTIO 0 terminal is turned on, and a voltage level value transitioned from Vref to O (ground) is applied to the second differentiator 90. Since the second differentiator 90 is set to a lower RC time constant value than the first differentiator 56, the second differentiator 90 makes a smaller kick pulse than the one produced by the first differentiator 56, and applies it to the focus driver.

In the above description of the present invention, specific embodiments have been described, but various modifications can be made without departing from the scope of the present invention. Therefore, the scope of the present invention should not be defined by the described embodiments, but should be defined by the equivalent of claims and claims.

As described above, the present invention can perform effective layer jumping by varying the value (force) of the kick pulse when jumping from the lower layer to the upper layer and jumping from the upper layer to the lower layer.

Claims (4)

A device for jumping between layers in a dual-layer optical disc drive, A focus driver driven by a predetermined control to focus the layer; A controller for controlling the jump between the layers; A first differentiator applying a first kick pulse to the focus driver by differentiating a voltage of a first level into a first time constant value by a jump control from a lower layer to an upper layer of the controller; And a second differentiator for applying a second kick pulse to the focus drive by differentiating a voltage of a second level into a second time constant value by a jump control from an upper layer to a lower layer of the controller. The apparatus of claim 1, wherein the size of the second kick pulse is less than that of gravity compared to the size of the first kick pulse. The apparatus of claim 1, wherein the first and second differentiators are differentiators composed of a capacitor and a resistor. 4. The apparatus of claim 3, wherein the capacitance of the first differentiator is greater than the capacitance of the second differentiator, assuming that the resistance values of the first and second differentiators are the same.

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