JPH08153364A - Optical disc master recording device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an optical disk master recording device which has a simple structure and can perform recording on an optical disk master according to an arbitrary linear velocity at a low cost. [Structure] The n setting means 12 sets the frequency dividers 6a, 6b, 6c at a frequency division ratio according to the linear velocity. Comparator 8
When the time information from the counter 7 and the time information in the time information table stored in the memory 11 coincide with each other, a outputs an instruction to the subtraction counter 9a, and the command value obtained by subtracting 1 from the carriage movement speed command value is a. The subtraction counter 9a outputs the digital / frequency converter 10a. This signal is frequency-divided by the frequency divider 6a at a predetermined frequency division ratio, and the movement of the head 2 is moved by the carriage 4 using the frequency-divided signal.
Controlled by. The control of the spindle 3 is similar to that of the carriage 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk master recording apparatus for recording information on an optical disk master with a constant linear velocity.

[0002]

2. Description of the Related Art FIG. 5 is a block diagram of a conventional optical disk master recording apparatus. In the optical disk master recording apparatus shown in FIG. 5, the CPU 22 incorporated in the minicomputer 21 performs processing according to the program stored in the program memory 23.

A signal of a predetermined frequency is output from the crystal oscillator 26 to the frequency divider 27, and a signal of a predetermined reference frequency is output from the frequency divider 27 to the counter 28. The counter 28 counts the signals from the frequency divider 27 and outputs time information according to the count result to the input port 21. Also,
Data such as a linear velocity, a track pitch, a recording start radius and a recording end radius are input from the keyboard 25 in accordance with a user's operation, and the CPU 2 is based on these data.
The carriage movement time information table and the spindle rotation time information table are generated by 2 and stored in the work memory 24.

When the cutting process by a device (not shown) is started, the CPU 22 determines that the time information from the input port 21 matches the time information shown in the carriage moving time information table stored in the work memory 24. Then, a value obtained by subtracting 1 from the current carriage movement speed command value is set as a new carriage movement speed command value, and this command value is output to the digital / frequency converter 31 via the output port 24 to control the carriage movement speed. The carriage moving speed is changed by the servo device 33. This changes the movement of the head 40.

When the CPU 22 determines in the cutting process that the time information from the input port 21 matches the time information indicated in the spindle rotation time information table stored in the work memory 24, the current spindle rotation is performed. A value obtained by subtracting 1 from the speed command value is set as a new spindle rotation speed command value, and this command value is output port 2
It is output to the digital / frequency converter 34 via 5, and the spindle rotation speed is controlled by the spindle rotation speed control servo device 34. As a result, the rotation of the optical disc master 42 is changed.

At this time, the digital / frequency converter 3
1 and 32 are the values instructed by the minicomputer to 1: 1
Converted to the pulse of the frequency corresponding to the speed control servo 3
It outputs to 3,34. Note that the specific relationship between the moving speed and the instruction value from the minicomputer is as follows: the speed control servos 33 and 34 and the digital / frequency converter 3
It is determined by setting the circuit constants 1 and 32.

[0007]

However, in the above-mentioned conventional optical disc master recording apparatus, in order to correspond to an arbitrary linear velocity, the carriage movement is performed by the processing by the CPU 22 according to the program stored in the program memory 23. Time information and counter 2 described in the time information table and the spindle rotation time information table
Since the comparison with the time information generated by 8 and the subtraction of the carriage movement speed command value and the spindle rotation speed command value are performed, there is a problem that the device configuration becomes complicated.

Further, in the above-described conventional optical disk master recording apparatus, when the frequency division ratio is changed, the CPU 22 performs a predetermined calculation in accordance with the change in the frequency division ratio, whereby the carriage movement speed command value and the spindle Since the rotation speed command value is generated, there is also a problem in that the device configuration becomes complicated in this respect as well.

The present invention has been made in view of the above-mentioned problems of the prior art, and is an optical disk master recording apparatus which is simple in structure and can inexpensively record on a disk master according to an arbitrary linear velocity. The purpose is to provide.

[0010]

In order to solve the above-mentioned problems of the prior art and achieve the above-mentioned object, an optical disk master recording apparatus of the present invention is a head for recording information on the surface of an optical disk master by a laser beam. An oscillator circuit for generating a pulse signal having a predetermined frequency; a first frequency divider circuit for dividing the pulse signal from the oscillator circuit at a predetermined frequency division ratio; and a signal from the first frequency divider circuit. A counter for generating a reference time signal, a storage circuit for storing change time data for changing the carriage movement speed command value and the spindle rotation speed command value, which are digital data, and the reference time signal and the storage circuit. A first comparison circuit for comparing the change time data for converting the carriage movement speed command value stored in the first comparison circuit and the comparison result of the first comparison circuit, A first addition / subtraction circuit for adding or subtracting a predetermined value to the carriage movement speed command value, and a carriage movement speed command value which is a calculation result of the first addition / subtraction circuit is converted into a carriage movement speed command signal of a predetermined frequency. A signal from the first conversion circuit, a second frequency division circuit that divides the carriage movement speed command signal from the first conversion circuit at a predetermined frequency division ratio, and a signal from the second frequency division circuit. A carriage for moving the head in the radial direction of the optical disc master in response to the reference time signal; and a second comparison circuit for comparing the change time data for converting the spindle rotation speed command value stored in the storage circuit. A second addition / subtraction circuit that adds or subtracts a predetermined value to / from the spindle movement speed command value according to the comparison result of the second comparison circuit, and the calculation result of the second addition / subtraction circuit. A second conversion circuit that converts a certain spindle movement speed command value into a spindle movement speed command signal having a predetermined frequency, and divides the spindle movement speed command signal from the second conversion circuit at a predetermined division ratio. A third frequency dividing circuit, a spindle for rotating the optical disk master about a central axis in response to a signal from the third frequency dividing circuit, and a frequency dividing ratio according to the linear velocity for the frequency dividing of 1 A circuit, a frequency dividing ratio setting circuit that sets the second frequency dividing circuit, and the third frequency dividing circuit.

[0011]

In the optical disk master recording apparatus of the present invention, the frequency division ratio setting means causes the first frequency division circuit, the second frequency division circuit and the third frequency division circuit to operate at frequency division ratios corresponding to linear velocities. Is set.

In the optical disc master recording apparatus of the present invention, the first comparison circuit compares the reference time signal from the counter with the change time data of the carriage movement speed command value from the storage circuit, and as a result of the comparison, If they match, the first addition / subtraction circuit performs a predetermined addition or subtraction on the carriage movement speed command value. The carriage movement speed command value, which is the calculation result in the first addition / subtraction circuit, is converted into a carriage movement speed command signal having a predetermined frequency in the first conversion circuit. The carriage movement speed command signal is frequency-divided by the second frequency dividing circuit at a predetermined frequency division ratio, and the frequency-divided signal is input to the carriage. In the carriage, movement control of the head in the radial direction of the optical disk master is performed based on the frequency-divided signal.

Similarly, in the second comparison circuit, the reference time signal from the counter and the change time data of the spindle rotation speed command value from the storage circuit are compared, and if the result of the comparison is that they match, In the second addition / subtraction circuit, a predetermined addition or subtraction is performed on the carriage movement speed command value. The spindle rotation speed command value, which is the calculation result in the second addition / subtraction circuit, is converted into a spindle rotation speed command signal of a predetermined frequency in the second conversion circuit. The spindle rotation speed command signal is divided by the third dividing circuit at a predetermined dividing ratio, and the divided signal is input to the spindle. The spindle controls the rotation of the optical disc master based on the frequency-divided signal.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG.
FIG. 3 is a block diagram of an optical disk master recording device showing an embodiment of the present invention.

First, the structure of the optical disk master recording apparatus of this embodiment will be described. In FIG. 1, reference numeral 1 denotes a disc master, which is about to be recorded. Reference numeral 2 is a head that is capable of irradiating a laser beam onto a disk master. A spindle 3 is composed of a motor, an encoder, and a speed control servo, on which a disk master is placed, and the disk master can be rotated in accordance with a command frequency.

A carriage 4 is composed of a motor, an encoder, and a speed control servo, and can move the head in accordance with the command frequency. Reference numeral 5 denotes an oscillator, which is connected to a crystal having a specific frequency and excites the crystal to generate a frequency serving as a reference for time information.

A frequency divider 6c is connected to the oscillator 5 and has a variable frequency division ratio by the n setting means 12 and outputs a required reference clock.

Reference numeral 7 denotes a counter, which is connected to the frequency divider 6c, and specifically is a 32-bit addition counter, which counts time information and outputs the count value to the comparators 8a and 8b. 8a and 8b are both comparators, which are a counter 7 and a memory 1.
The element of the time information table connected to 0 and the time information table stored in the memory 10 is compared with the time information of the counter 7, and if they match, a pulse indicating that fact is generated and the next element of the time information table is referred to for comparison. The value.

Both 9a and 9b are subtraction counters, which are connected to the comparators 8a and 8b, respectively, and subtract one by one from the initial command value set by the pulse of the comparators 8a and 8b. Digital-frequency converters 10a and 10b are connected to the subtraction counters 9a and 9b, respectively, and convert the command values indicated by the subtraction counters 9a and 9b into one-to-one corresponding frequencies.

Frequency dividers 6a and 6b are connected to the digital / frequency converters 10a and 10b, respectively, and the frequency dividing ratio is variable by the n setting means 12 to generate the command frequency. Reference numeral 11 is a read-only memory, which stores a time information table which is a result of performing a calculation beforehand according to a certain linear velocity.

Reference numeral 12 is an n setting means, which is a frequency divider 6a, 6b,
This is a switch for setting the division ratio of 6c. The frequency division ratios of the frequency dividers are changed in conjunction with each other according to the setting state.

Next, the operation of the optical disk master recording apparatus of this embodiment will be described. The user sets the frequency division ratio of the frequency dividers 6a, 6b, 6c to 1 / N ₁ by the n setting means 12 as a preparation for performing the recording process on the master disc. Here, N ₁ is a real number of 1 or more. The head 2 is moved to the recording start radius by means not shown. Subsequently, an appropriate initial command value is set in the subtraction counter 9b, and the disc 1 starts rotating. After the disk 1 becomes substantially stable in operation, an appropriate initial command value is set in the subtraction counter 9a, the counter 7 is reset, and the first element of the time information table is referred to for the comparison values 8a and 8b. Is set to. As a result, the actual recording process is started.

During the actual recording process, the counter 7 counts the frequency obtained by dividing the frequency from the oscillator 5 by the frequency divider 6c. Therefore, a count value proportional to the elapsed time from the start of the recording process is output to the comparators 8a and 8b. On the other hand, the memory 11 stores a time information table for carriage control and a time information table for spindle control. The two time information tables are one-dimensional arrays of times according to the reference clock.

FIG. 2 shows an example of these time information tables. The element Tc (k) of the time information table for carriage control is defined by the following equation (1), where k is a non-negative integer.

[0025]

## EQU00001 ## Tc (k) = time at which the carriage movement speed command value becomes (initial speed command value-k) (1)

The element Tc is specifically represented by 32-bit information. This information is calculated based on the carriage circuit constants. The element Ts (k) of the time information table for spindle control is defined by the following equation (2), where k is a non-negative integer.

[0027]

## EQU00002 ## Ts (k) = time at which the spindle rotation speed command value becomes (initial speed command value-k) (2)

The element Ts (k) is specifically represented by 32-bit information. This information was calculated based on the spindle circuit constants.

Since the comparators 8a and 8b compare the count value output from the counter 7 with the elements of the time information table and generate a pulse each time they match, the subtraction counters 9a and 9b.
Since b is subtracted by one each time, the digital / frequency converters 10a and 10b generate gradually lower frequencies. This frequency is divided by the frequency dividers 6a and 6b and becomes a command frequency for driving the carriage and the spindle.

FIG. 3 is a diagram for explaining the transition of the command frequency for the carriage and the spindle. As shown in FIG. 3, the carriage and the spindle whose speed is controlled by the change of the command frequency change such that the carriage moving speed and the spindle rotating speed decrease, and as a result, the recording processing in which the linear speed becomes constant is performed. Be seen.

While the recording process is being performed as described above, when it is detected by the means (not shown) that the head has reached the recording end radius, the apparatus performs the ending process and the sequence ends.

By switching the n setting means 12,
The frequency division ratio of the frequency dividers 6a, 6b, 6c is 1 / N ₂ . Here, N ₂ is a real number of 1 or more, and N ₁ ≠ N ₂ . As a result, in the recording process, the frequency input to the counter 2 has a frequency division ratio set in the frequency divider 6c of 1 / N.
_Since it becomes N ₁ / N ₂ times that when it is ₁ , the time information indicated by the counter 2 also becomes N ₁ / N ₂ times. That is,
The generation interval of the coincidence signals output from the comparators 8a and 8b is N ₂
/ N ₁ , and the transition of the command value indicated by the subtraction counters 9a and 9b becomes N ₁ / N ₂ times the speed.

Further, the digital / frequency converter 10
Since the frequencies output from a and 10b are also divided into 1 / N ₂ by the frequency dividers 6a and 6b, the command frequency input to the spindle 3 and the carriage 4 is also the frequency division ratio of the frequency dividers 6a and 6b. This is N ₁ / N ₂ times as much as when it was 1 / N ₁ . That is, the rotational speed of the disk 1 and the moving speed of the head 2 are N ₁ / N ₂ times higher. This indicates that the linear velocity in the recording process becomes N ₁ / N ₂ times.

FIG. 4 shows n setting means (selection switch) 12
FIG. 6 is a diagram for explaining a change in transition of a command frequency due to switching of FIG. Specifically, N ₁ in the above description is 1
00, that is, when the frequency division ratio is set to 1/100, a time information table is prepared so that the linear velocity in the recording process becomes the linear velocity 130 [cm / s], and N ₂ is set to 50, that is, the minute by the n setting means By setting the circumference ratio to 1/50, the linear velocity in the actual recording process is doubled to 260 [cm / s].
Becomes

Further, N ₂ is 200, that is, the division ratio is 1 /
By setting 4, the linear velocity is halved to 65 [cm / s]
Becomes Of course, since N ₂ is a real number of 1 or more, it goes without saying that the recording process can be performed at a linear velocity other than the above two examples. As described above, according to the optical disc master recording apparatus of the present embodiment, with a simple device configuration,
From one time information table, it is possible to generate a command frequency that enables recording at an arbitrary linear velocity.

[0036]

According to the optical disk master recording apparatus of the present invention, it is possible to generate a command frequency capable of recording at an arbitrary linear velocity from one time information table with an inexpensive and simple structure. .

[Brief description of drawings]

FIG. 1 is a block diagram of an optical disk master recording apparatus showing an embodiment of the present invention.

FIG. 2 is a diagram illustrating a time information table for carriage control and a time information table for spindle control according to the present embodiment.

FIG. 3 is a diagram for explaining transition of command frequencies for a carriage and a spindle.

FIG. 4 is a diagram for explaining a change in transition of a command frequency due to switching of n setting means (selection switch).

FIG. 5 is a configuration diagram of a conventional optical disc master recording device.

[Explanation of symbols]

 1 ... Disk master 3 ... Spindle 4 ... Carriage 5 ... Oscillator 6a, 6b ... Frequency divider 7 ... Counter 8a, 8b ... Comparator 9a, 9b ... Subtraction Counters 10a, 10b ... Digital / frequency converter 11 ... Read-only memory 12 ... n Setting means

Claims (1)

[Claims] 1. A head for recording information on the surface of an optical disc master by a laser beam, an oscillation circuit for generating a pulse signal of a predetermined frequency, and a pulse signal from the oscillation circuit for dividing the pulse signal at a predetermined division ratio. 1 frequency dividing circuit, a counter for counting signals from the first frequency dividing circuit and generating a reference time signal, and a change time for changing the carriage moving speed command value and the spindle rotation speed command value which are digital data. A storage circuit that stores data, a first comparison circuit that compares the reference time signal with change time data that converts the carriage movement speed command value stored in the storage circuit, and a first comparison circuit A first addition / subtraction circuit for adding or subtracting a predetermined value to / from the carriage movement speed command value according to the comparison result; and a calculation result of the first addition / subtraction circuit. A first conversion circuit for converting a carriage movement speed command value to a carriage movement speed command signal having a predetermined frequency, and dividing the carriage movement speed command signal from the first conversion circuit at a predetermined frequency division ratio. A second frequency dividing circuit, a carriage for moving the head in the radial direction of the optical disk master according to a signal from the second frequency dividing circuit, a spindle rotation stored in the reference time signal and the storage circuit. A second comparison circuit for comparing the change time data for converting the speed command value, and a second addition / subtraction for adding or subtracting a predetermined value to the spindle movement speed command value according to the comparison result of the second comparison circuit. A circuit, a second conversion circuit that converts a spindle movement speed command value, which is a calculation result of the second addition / subtraction circuit, into a spindle movement speed command signal having a predetermined frequency; A third frequency dividing circuit for frequency-dividing the spindle moving speed command signal from the converting circuit according to a predetermined frequency division ratio, and the optical disc master centered on the central axis in accordance with the signal from the third frequency dividing circuit. And a spindle to be rotated as described above, the frequency dividing circuit according to the linear velocity, the frequency dividing circuit of the first, the second
Optical disk master recording device having a frequency dividing circuit and a frequency dividing ratio setting circuit for setting the third frequency dividing circuit.