JPH05250686A - Device for controlling pickup movement - Google Patents

Abstract

PURPOSE:To provide a device for controlling pickup movement which can perform stable tracking operation in spite of variation of entering speed. CONSTITUTION:This device is provided with comparing means 1 and 2 which generate a binary signal based on a track cross signal, counting means 3, 4, 5 and 6 which perform counting operation based on the binary signal, and a generating means 8 for deceleration energy quantity which controls deceleration energy quantity supplied to a lens moving device in accordance with a reciprocal of a counting value sent from the counting means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pickup movement control device provided in an optical disk device for recording and reproducing optical information.

[0002]

2. Description of the Related Art When reproducing optical information from a disc on which optical information is written or recording optical information on the disc, a recording / reproducing light for reading / writing the optical information is desired on the disc. It is necessary to perform a seek operation to match the track. In order to perform this seek operation at high speed, the following three operations are used together: a rough seek operation, a multi-track move operation (hereinafter, this operation is referred to as an M track move operation), and a 1-track move operation. The coarse seek operation is a moving operation used when the recording / reproducing light moves from about 512 to about 22000 tracks, and moves a so-called track cross signal obtained when the recording / reproducing light crosses a track. This is a movement operation in which the carriage itself having a so-called pickup is moved and the movement amount of the carriage is detected by a signal obtained from a linear encoder without being used as a judgment material for the amount detection. In the M track move operation, the recording / reproducing light is 51 at maximum.
In the operation used when moving two tracks, the recording / reproducing light transmitting lens that emits and receives the recording / reproducing light is moved, and the carriage is accompanied by the movement of the lens. This is a moving operation using the track cross signal as a material for detecting the amount of movement. The one-track move operation is an operation of moving the recording / reproducing light transmitting lens by one track, and is a moving operation using the track cross signal as a material for detecting the amount of movement.

The frequency of the track cross signal obtained by the recording / reproducing light moving the track by each of these operations depends on the speed of the moving operation, and is 50 kHz or more in the coarse seek operation in which the recording / reproducing light moves at the highest speed. It is about 100 KHz, about 8 KHz to 10 KHz in the M track move operation, and about 0.8 KHz to 1 KHz in the one track move operation. Therefore, there is a difference of about 100 times in the frequency of the track cross signal between the 1-track move operation and the coarse seek operation.

[0004]

In order to move the recording / reproducing light, the carriage or the recording / reproducing light transmitting lens is first accelerated in the moving direction, and then the recording / reproducing light is matched with the vicinity of a desired track or the track. First, it is necessary to reduce the moving speed of the carriage or the recording / reproducing light transmitting lens.

In order to move the recording / reproducing light transmitting lens to a desired track, first, as shown in FIG.
In the period, a drive voltage is applied to the lens moving device to accelerate the recording / reproducing light transmitting lens, and the deceleration is performed in the period (c) after the speed control period which is the period (b), and finally the recording / reproducing light is transmitted. In the period (d) for performing the operation of matching the target track with the target track, only deceleration energy is supplied to the lens moving device so that the recording / reproducing light transmitting lens moves in the opposite direction to the moving direction of the recording / reproducing light transmitting lens. After an operation period of reducing the moving speed of the recording / reproducing light transmitting lens (hereinafter referred to as final tracking operation), a tracking operation is started in a period (e). In order to shift from the period (c) to the period (d), the movement of the recording / reproducing light transmitting lens is moved until the frequency of the track cross signal obtained by the movement of the recording / reproducing light transmitting lens becomes about 2 kHz or less. It is necessary to decelerate, and if such deceleration is not made, it becomes difficult to shift to the period (d), and the pickup equipped with the recording / reproducing light transmitting lens will be in a runaway state, for example. ..

Therefore, conventionally, the moving speed of the recording / reproducing light transmitting lens is controlled to be reduced to a speed at which the period (d) can be shifted. However, the period (c) is shifted to the period (d). Moving speed of the recording / playback light transmission lens
(Hereinafter, this speed is referred to as the final tracking operation inrush speed.) Varies depending on various conditions of the disk device. However, the conventional pickup movement control device does not control the deceleration amount to be supplied to the lens moving device according to the final tracking operation rush speed. Therefore, there is a problem that a stable tracking operation cannot be performed due to a change in the time until it becomes possible to shift to the period (e), that is, a so-called settling time, due to a change in the final tracking operation inrush speed. The present invention has been made to solve such a problem, and it is possible to perform a stable tracking operation even if the final tracking operation inrush speed varies depending on various conditions of the disk device. Also, it is an object of the present invention to provide a pickup movement control device that can perform a stable movement speed control operation of a recording / reproducing light transmitting lens even in the period (c).

[0007]

According to the present invention, recording / reproducing light for reading / writing optical information is moved to a target track on an optical information recording medium. An acceleration / deceleration period for supplying acceleration or deceleration energy to the lens moving means for moving the reproduction light transmitting lens, and a period for supplying only the deceleration energy to the lens moving means for finally stopping the movement of the recording / reproduction light transmitting lens. In the pickup movement control device that controls the movement of the recording / reproducing light transmitting lens during the final tracking operation period from the start of the supply of deceleration energy to the stop of the movement of the recording / reproducing light transmitting lens, acceleration to the lens moving means or By supplying deceleration energy, the recording / reproducing light transmitting lens is moved, whereby the recording / reproducing light is transmitted. Comparing means for comparing the voltage value and the set voltage value in the track cross signal generated by traversing the track on the dynamic information recording medium, and transmitting the comparison result as a binary signal, and the comparing means. While at least one of the high level and the low level of the binarized signal, the counting operation is performed from the initial value for each pulse, and the counting means for transmitting the counted value obtained as a result of the counting operation, and the counting means And a deceleration energy amount generation means for generating and transmitting a deceleration energy amount control signal for controlling the deceleration energy amount supplied to the lens moving means according to the count value.

With this configuration, the counting means is
The counting operation is performed based on the binarized signal sent from the comparing means, and the count value counted by the counting means represents the reciprocal of the moving speed of the recording / reproducing light transmitting lens. Therefore, the count value sent by the counting means at the time of transition to the final tracking operation period is a value that is inversely proportional to the transition speed of the recording / reproducing light transmission lens. The deceleration energy amount generation means generates the deceleration energy amount control signal according to the count value sent by the counting means, that is, in inverse proportion to the magnitude of the count value. Therefore, the counting means and the deceleration energy amount generation means operate so as to be able to supply the deceleration energy amount to the lens moving means in proportion to the moving speed of the recording / reproducing light transmitting lens at the time of transition to the final tracking operation period.

Further, according to the present invention, the deceleration energy amount generation means may be configured to generate the deceleration energy amount control signal by multiplying the reciprocal value of the count value by any positive or negative value. Also, the deceleration energy amount generation means may send out a deceleration energy amount control signal made of digital data. In this case, the deceleration energy amount control signal is converted into an analog signal to move the lens. It may be configured to include a D / A conversion means for sending to the means.

With this configuration, the deceleration energy amount generation means acts so as to send digital data.

Further, according to the present invention, the first control signal for instructing the acceleration / deceleration period, the second control signal for instructing the final tracking operation period, and the moving speed of the upper recording / reproducing light transmitting lens are controlled to a target speed. Therefore, the control means for sending out the target count value corresponding to the target moving speed, the count value is supplied from the counting means, while the target count value is supplied from the control means, and the target count value from the count value. Subtracting means for subtracting and decelerating count value, and the subtracting count value is supplied from the subtracting means, while the deceleration energy amount control signal is supplied from the deceleration energy amount generating means,
When the first control signal is supplied from the control means, the subtraction count value is selected and the second means is selected from the control means.
It is also possible to include a selecting means for selecting and transmitting the deceleration energy amount control signal when the control signal is supplied.

With this configuration, while the control means sends the first control signal, the selection means sends the subtraction count value supplied from the subtraction means to the D / A conversion means, and the control means outputs the second count value. While the control signal is being sent, the selection means outputs the deceleration energy amount control signal D supplied from the deceleration energy amount generation means.
/ A Send to A conversion means. Therefore, the control means and the selection means supply the deceleration energy amount to the lens moving means in proportion to the moving speed of the recording / reproducing light transmitting lens at the time of transition to the final tracking operation period, and also during the acceleration / deceleration period. It acts to supply the deceleration energy amount to the lens moving means according to the target moving speed of the light transmitting lens.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the pickup movement control device of the present invention will be described below with reference to FIGS. As shown in FIG. 2A, a track cross signal that fluctuates in the positive side voltage and the negative side voltage is supplied, and the set positive side reference voltage value (+
When the positive side voltage value of the track cross signal exceeds Vr), a high (H) level signal is generated and transmitted, and when the positive side reference voltage value is less than the positive side voltage value of the track cross signal, it is low ( When the positive side comparator 1 for generating and transmitting the L) level signal and the track cross signal are supplied, and the negative side voltage value of the track cross signal exceeds the set negative side reference voltage value (-Vr). Generates and sends out H level signal,
The output side of the negative side comparator 2 which generates and sends out the L level signal when the negative side voltage value of the track cross signal does not satisfy the negative side reference voltage value is both the positive side and negative side comparators. It is connected to the edge detector 3 which detects the falling edge in the binarized signal shown in FIG.
The edge detector 3 generates an LAT signal rising in synchronization with the falling edge of the binarized signal and an EDGE signal rising in synchronization with the falling edge of the LAT signal. The LAT signal is a clock signal. Is sent to the latch circuit 6 described later, and the EDGE signal is sent to the AR terminal of the counter 5 described later.

The counter 5 performs a counting operation of a 9-bit count value, and outputs a signal having a frequency of 10 MHz by 1/8.
The clock signal supplied from the clock signal generation circuit 4 that multiplies the clock signal having the frequency of 1.25 MHz by
As shown in FIG. 2E, the counting operation is started from the time when the EDGE signal is supplied, and the counting operation is continued until the next EDGE signal is supplied. The count value thus counted is proportional to the lengths of the H and L periods in the binarized signal. That is, a large count value means that the H and L periods are long, that is, the frequency of the track cross signal is low, that is, the moving speed of the recording / reproducing light transmitting lens is slow, and conversely, the count value is The small value means that the H and L periods are short, that is, the frequency of the track cross signal is high, that is, the moving speed of the recording / reproducing light transmitting lens is fast. In this way, the count value represents the reciprocal of the moving speed of the recording / reproducing light transmitting lens.

The output terminal of the counter 5 is connected to the latch circuit 6, and the latch circuit 6 latches the count value sent by the counter 5 each time the LAT signal is supplied. The count value sent from the counter 5 to the latch circuit 6 is the higher 6 bits of the count value of 9 bits (Q8, Q7, Q6, Q5, Q).
4 and Q3). When the control circuit 13 outputs a control signal for instructing a final tracking operation, which will be described later, the latch circuit 6 uses the LAT signal supplied immediately after the control signal is supplied to count the value of the counter 5. Latch. The output side of the latch circuit 6 is connected to the subtractor 7 and the reciprocal number generation circuit 8, and the output sides of the subtractor 7 and the reciprocal number generation circuit 8 are connected to the multiplexer 9, respectively.

The subtractor 7 is an operation other than the operation of finally tracking the recording / reproducing light on the track on the disc, and is a recording / reproducing light transmitting lens as shown in the periods (a) to (c) of FIG. General deceleration or acceleration operation related to movement
(Hereinafter referred to as acceleration / deceleration operation) The above-mentioned acceleration is a concept that includes not only constant increase in speed but also constant speed. The subtractor 7 adjusts the amount of energy supplied to the lens moving device in order to reduce or increase the frequency of the track cross signal to a target frequency, that is, to reduce or increase the moving speed of the recording / reproducing light transmitting lens. To decide. Specifically, the subtractor 7 subtracts the count value sent from the control circuit 13 and corresponding to the target frequency (hereinafter referred to as the target count value) from the count value supplied from the latch circuit 6. , And outputs the subtracted count value to the multiplexer 9. The sign terminal for sending the positive and negative sign data in the subtraction count value is connected to the disable terminal of the transmission gate 11 whose input side is grounded and whose output side is connected to the DA converter 10, and the input side which is connected to a -5V power source. The output side is connected to each of the enable terminals of the transmission gate 12 connected to the DA converter 10. When the count value becomes negative, the borrow signal is transmitted, and when it is positive, the borrow signal is not transmitted.

On the other hand, the reciprocal number generating circuit 8 stops the moving recording / reproducing light transmitting lens in order to finally track the recording / reproducing light on the track on the disk as shown in the period (d) of FIG. Thus, it is used in the final tracking operation for determining the amount of deceleration energy supplied to the lens moving device. Such an inverse number generating circuit 8 is, for example, R
It is composed of an OM (Read Only Memory) and stores a value obtained by multiplying the reciprocal of the count value by K in correspondence with each supplied count value. In the present embodiment, the reciprocal number generation circuit 8 is composed of a ROM, but it may be composed of a logic circuit.
Further, K is a conversion constant, and "0" is set at the time of designing the device so that a predetermined count value can be sent from the reciprocal number generation circuit 8 in response to a change in the count value supplied from the latch circuit 6. Except for this, it is a value that is arbitrarily set, and may be "1" as a matter of course. In addition, the reciprocal number generation circuit 8 includes a control circuit 13
When the control signal for instructing the final tracking operation is sent by, the count value of the counter 5 at the time of transition to the final tracking operation is supplied from the latch circuit 6.

The count value sent by the latch circuit 6 is a value corresponding to the reciprocal of the moving speed of the recording / reproducing light transmitting lens. That is, the fact that the count value sent out by the latch circuit 6 is small means that the frequency in the track cross signal is high, which means that the moving speed of the recording / reproducing light transmitting lens is fast. Therefore, in such a case, since a large deceleration energy is required to stop the movement of the recording / reproducing light transmitting lens, the reciprocal number generating circuit 8 needs to send a large count value corresponding thereto. On the contrary, when the transmission count value of the latch circuit 6 is large, the reciprocal number generation circuit 8 must transmit a small count value. As described above, the reciprocal number generation circuit 8 outputs a value corresponding to the reciprocal number of the supplied count value, and therefore operates to satisfy the above-described operation. or,
The reciprocal number generation circuit 8 sends to the multiplexer 9 a value obtained by multiplying the reciprocal number of the count value sent from the latch circuit 6 by K at the transition point to the final tracking operation.

The output side of the multiplexer 9 converts the digital data sent from the multiplexer 9 into a voltage value composed of an analog signal which can be supplied to the lens moving device.
It is connected to the A converter 10, and the output side of the D / A converter 10 is connected to an amplifier and a moving coil (not shown) that constitute the lens moving device. When the control signal instructing the acceleration / deceleration operation is supplied from the control circuit 13, the multiplexer 9 selects the count value sent by the subtractor 7 and outputs the control signal instructing the final tracking operation. When supplied from the control circuit 13, the count value sent by the reciprocal number generation circuit 8 is selected, and one of the selected count values is sent to the D / A converter 10.

The operation of the pickup movement control device thus constructed will be described below. Counter 5
According to the EDGE signal sent by the edge detector 3, FIG.
As shown in (e), the adding and counting operation is performed corresponding to the H period of each binarized signal transmitted by the positive side comparator 1 and the negative side comparator 2. That is, the counter 5 starts the addition counting operation by supplying the EDGE signal corresponding to the rising edge of the binarized signal, and E corresponding to the falling edge of the binarized signal.
The addition counting operation is stopped by the supply of the DGE signal, and the addition counting value is reset.

The count value thus counted by the counter 5 is latched by the latch circuit 6 when the LAT signal sent from the edge detector 3 is supplied to the latch circuit 6, and the latched count value ( Hereinafter, it may be referred to as a latch count value) is sent to the subtractor 7 and the reciprocal number generation circuit 8.
The subtractor 7 accelerates or decelerates the moving recording / reproducing light transmitting lens up to a target speed, so that the count value corresponding to the target speed, for example, (B5, B4, B3,
A target count value consisting of 6 bits (B2, B1, B0) is supplied, and the subtractor 7 is a count value corresponding to the current moving speed of the recording / reproducing light transmitting lens and is a count value supplied from the latch circuit 6, For example, in this embodiment, (A5, A4, A3, A2,
The target count value is subtracted from the 6-bit latch count value (A1, A0), and the subtracted value is sent to the multiplexer 9.

On the other hand, the reciprocal number generating circuit 8 sends the stored count value to the multiplexer 9 in correspondence with the latch count value supplied from the latch circuit 6. As described above, the reciprocal number generating circuit 8 outputs to the multiplexer 9 a small count value corresponding to the moving speed of the recording / reproducing light transmitting lens when the moving speed of the recording / reproducing light transmitting lens is low.
When the moving speed of the recording / reproducing light transmitting lens is high, a large count value is sent out.

When the control circuit 13 supplies a control signal to the multiplexer 9 to instruct an acceleration / deceleration operation, the multiplexer 9 selects the count value supplied from the subtractor 7 and sets the count value to D. / Send to A converter 10.

The D / A converter 10 generates and outputs an analog signal for controlling the amount of energy supplied to the lens moving device in proportion to the size of the count value supplied from the multiplexer 9. Incidentally, the D / A converter 10 lowers the moving speed of the recording / reproducing light transmitting lens because the moving speed of the recording / reproducing light transmitting lens is high when the borrow signal is H according to the H and L of the borrow signal sent from the multiplexer 9. On the contrary, when the borrow signal is L, the moving speed is slow, so that the moving speed is increased.

On the other hand, when a control signal instructing the final tracking operation is supplied from the control circuit 13 to the multiplexer 9, the multiplexer 9 selects the count value sent by the reciprocal number generation circuit 8. As described above, the count value thus selected is the count value at the time of shifting to the final tracking operation, and is proportional to the moving speed of the recording / reproducing light transmitting lens at the time of shifting to the final tracking operation. It is a value. Then, the multiplexer 9 sends the selected count value to the D / A converter 10.

The D / A converter 10 generates and outputs an analog signal for controlling the amount of energy supplied to the lens moving device in proportion to the size of the count value supplied from the multiplexer 9. Therefore, when the count value supplied from the multiplexer 9 is large, that is, when the moving speed of the recording / reproducing light transmitting lens at the time of shifting to the final tracking operation is fast, the D / A converter 10 sends a large deceleration energy to the lens moving device. Is sent out. Therefore, a voltage having a large "E" value shown in FIG. 3C is supplied to the moving coil of the lens moving device. On the contrary, when the count value supplied from the multiplexer 9 is small, that is, when the moving speed of the recording / reproducing light transmitting lens at the time of shifting to the final tracking operation is slow,
The D / A converter 10 sends a control signal such that a small deceleration energy is supplied to the lens moving device. Therefore, a voltage having a small “E” value shown in FIG. 3C is supplied to the moving coil of the lens moving device. Since the final tracking operation is performed only when the movement of the recording / reproducing light transmission lens is always stopped, the multiplexer 9 outputs a signal corresponding to the borrow signal regardless of the borrow signal. Not even.

As described above, in the pickup movement control device of this embodiment, when the final tracking operation is performed, the pickup movement control device supplies the moving coil in proportion to the moving speed of the recording / reproducing light transmitting lens immediately before the transition. Since the amount of deceleration energy to be changed can be changed, even if the moving speed of the recording / reproducing light transmitting lens changes at the time of transition to the final tracking operation period, the time required to complete the tracking operation after the transition to the final tracking operation is always the same. Time can be set, stable tracking operation can be performed, and stable movement speed control of the recording / reproducing light transmitting lens can be performed even during the acceleration / deceleration period.

[0028]

As described above in detail, according to the present invention, the deceleration energy is supplied to the lens moving means in proportion to the moving speed of the recording / reproducing light transmitting lens. Even at the time of transition to, the deceleration energy can be supplied to the lens moving means in proportion to the moving speed of the recording / reproducing light transmitting lens, and the moving speed of the recording / reproducing light transmitting lens at the time of shifting to the final tracking operation period is Even if it fluctuates, stable tracking operation can be performed. Further, according to the present invention, the subtracting means is provided so that appropriate deceleration energy can be supplied to the lens moving means during the acceleration / deceleration period, and further the speed is reduced to the lens moving means in proportion to the moving speed of the recording / reproducing light transmitting lens. By supplying energy, deceleration energy can be supplied to the lens moving means in proportion to the moving speed of the recording / reproducing light transmitting lens at the time of transition to the final tracking operation period, and during the acceleration / deceleration period. Can stably control the moving speed of the recording / reproducing light transmitting lens, and can perform stable tracking operation during the final tracking operation period.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of a pickup movement control device of the present invention.

FIG. 2 is a timing chart showing the operation of the components shown in FIG.

FIG. 3 is a waveform showing a drive voltage to the lens moving device, a track cross signal, and a voltage value supplied to the lens moving device during the final tracking operation from the start of movement of the recording / reproducing light transmitting lens to the completion of tracking.

[Explanation of symbols]

1 ... Positive side comparator, 2 ... Negative side comparator, 5 ... Counter, 6 ...
Latch circuit, 7 ... Subtractor, 8 ... Inverse number generation circuit, 9 ... Multiplexer, 10 ... D / A converter, 13 ... Control circuit.

Claims (5)

[Claims] 1. A lens moving means for moving a recording / reproducing light transmitting lens, through which the recording / reproducing light is transmitted, for moving the recording / reproducing light for reading / writing optical information to a target track on the optical information recording medium. An acceleration / deceleration period in which acceleration or deceleration energy is supplied, and a period in which only deceleration energy is supplied to the lens moving means to finally stop the movement of the recording / reproducing light transmitting lens, and the recording is started from the start of deceleration energy supply. In the pickup movement control device for controlling the movement of the recording / reproducing light transmitting lens with respect to the final tracking operation period until the movement of the reproducing light transmitting lens is stopped, the recording / reproducing light is supplied by supplying acceleration or deceleration energy to the lens moving means. The transmission lens moves so that the recording / reproducing light crosses the track on the optical information recording medium. Comparing the voltage value and the set voltage value in the track cross signal generated by the above, and transmitting the comparison result as a binary signal, and a high or low level of the binary signal transmitted by the comparing means. During at least one of the levels, the counting operation is performed from the initial value for each pulse, and the counting means for sending the counting value obtained as a result of the counting operation, and the counting value sent by the counting means A deceleration energy amount generation means for generating and transmitting a deceleration energy amount control signal for controlling the deceleration energy amount supplied to the lens moving means, and a pickup movement control device. 2. The pickup movement control device according to claim 1, wherein the deceleration energy amount generation means generates the deceleration energy amount control signal by multiplying the reciprocal value of the count value by any positive or negative value. .. 3. A deceleration energy amount control means for outputting a deceleration energy amount control signal consisting of digital data, wherein the deceleration energy amount control means converts the deceleration energy amount control signal into an analog signal and sends it to the lens moving means. 3. The pickup movement control device according to claim 1, further comprising D / A conversion means. 4. A first control signal for instructing the acceleration / deceleration period, a second control signal for instructing the final tracking operation period, and a target movement for controlling the moving speed of the upper recording / reproducing light transmitting lens to a target speed. The control means for sending out the target count value corresponding to the speed, the count value is supplied from the counting means, while the target count value is supplied from the control means, and the target count value is subtracted from the count value. Subtraction means for sending the deceleration count value, the subtraction count value is supplied from the subtraction means, the deceleration energy amount control signal is supplied from the deceleration energy amount generation means, and the first control signal is sent from the control means. Selecting means for selecting the subtraction count value when supplied, and selecting and transmitting the deceleration energy amount control signal when the second control signal is supplied from the control means. Pickup movement control apparatus according to claim 3, further comprising a. 5. The pickup movement control device according to claim 1, wherein the counting means sends only the count value at the time of transition from the acceleration / deceleration period to the final tracking period.