KR200235354Y1 - Optimal laser recording power detection device - Google Patents

Abstract

The present invention relates to an optimum laser recording power detection apparatus. In the related art, the A / D conversion unit can be used in a short time to obtain the highest or lowest digital value by using the A / D conversion unit to detect an optimal parameter (β) value. Since an arbitrary channel needs to be changed, the A / D converter needs high-speed operation. Accordingly, in order to develop into a high-speed recording device, there is a problem that the product price increases as the system added thereto increases.

Therefore, in order to solve the above problems, the present invention configures a digital logic circuit for detecting an optimal parameter β from an RF signal of a laser reflection amount by irradiating a laser on a disk surface in a recordable optical disk. It is an optimum laser recording power detection device that can reduce the price of the product by simply detecting the optimum parameter (β) in the RF signal waveform according to the time difference of the square wave constant section.

Description

Optimal Laser Recording Power Detection Device

1 is a block diagram showing the structure of a conventional optimum laser recording power detection device.

2 (a) to (c) are output waveform diagrams of respective parts of a conventional optimum laser recording power detection device.

3 is a block diagram showing the structure of the present invention optimized laser recording power detection device.

4 (a) to (d) are output waveform diagrams of respective parts of the optimum laser recording power detection device of the present invention.

* Explanation of symbols for main parts of the drawings

11: square wave switching unit 12: high frequency oscillation unit

13: high section counter 14: first comparison section

15: first register section 16: low section counter section

17: second comparison part 18: second register part

19: micom

The present invention relates to an apparatus for detecting an optimum laser recording power, and in particular, by constructing a digital logic circuit for detecting an optimal parameter (β) from an RF signal of a laser reflection amount by irradiating a laser of a disk surface on a recordable optical disk. In addition, the present invention relates to an optimum laser recording power detection device for easily detecting an optimum parameter β in RF.

The configuration and operation of the conventional optimum laser recording power detection apparatus will be described with reference to FIG. 1 as follows.

First, the peak level detector 1 detects and holds the peak level of the AC-coupled RF signal waveform input through the capacitor C1, and the peak level detector 1 detects the peak level. The first low pass filter unit 2 filtering the highest level of the held RF signal waveform to remove ripple, and detecting the lowest level of the AC-coupled RF signal waveform input through the condenser C1. Hold the minimum level detector 3 to hold and the second low pass filter 4 to remove the ripple by filtering the minimum level of the RF signal waveform held and detected by the minimum level detector 3. And a switch SW1 for switching to select the highest or lowest level of the RF signal waveform from which the ripple phenomenon is removed by the first or second low pass filter unit 2 or 4, and the switch SW1. Depending on the switching operation A (A) / D (D) converter (5) for converting the maximum or minimum level of the RF signal waveform from which the phenomena has been eliminated into a maximum or minimum digital value (A1) or A2 while outputting it to an arbitrary channel. And the maximum or minimum value while outputting a constant control signal to switch an arbitrary channel for a predetermined time according to the highest or minimum digital value A1 (A2) converted and inputted by the A / D converter 5. It consists of a microcomputer 6 which detects the optimal parameter β having calculated the digital values A1 and A2 and controls the power level of the laser.

The operation of the conventional optimum laser recording power detection device configured as described above is as follows.

First, when the AC-coupled RF signal waveform input through the condenser C1 is input to the system, as shown in FIG. 2 (a), the peak level detection unit 1 is shown in FIG. 2 (b). As described above, the highest level A1 of the AC-coupled RF signal waveform is detected and held, and then output to the first low pass filter unit 2, which is detected by the first low pass filter unit 2. While the filtering operation is performed to remove ripple of the peak level A1 of the held RF signal waveform, the peak level A1 of the filtered RF signal waveform is changed to an arbitrary value of the A / D converter 5. Input to the channel.

On the other hand, the lowest level detector 3 detects and holds the lowest level A2 of the input AC-coupled RF signal waveform as shown in FIG. 2C, and then the second low pass filter unit ( 4), and the second low pass filter unit 4 performs a filtering operation to remove ripples of the lowest level A2 of the detected and held RF signal waveform. The lowest level A2 of the signal waveform is input to any channel of the A / D converter 5.

At this time, the A / D conversion section 5 is the highest level (A1) of the RF signal waveform or the lowest level of the RF signal waveform filtered by the first or second low pass filter (2) (4) The A2 is converted into the digital values A1 and A2, and then output to the microcomputer 6.

Accordingly, the microcomputer 6 converts the A / D conversion unit within a short time so that a certain time difference between channels is not large for a predetermined time according to the digital value A1 (A2) of the highest or lowest value of the converted RF signal waveform. A constant control signal is outputted to a switch SW1 which performs a selective switching operation to switch the digital value A1 or A2 of the highest value or the lowest value input to any channel of (5), and the switch SW1 outputs a microcomputer ( During the switching operation according to the constant control signal output from 6), the highest level A1 of the RF signal waveform or the lowest level A2 of the RF signal waveform is selected.

In addition, in the microcomputer 6

As described above, while calculating the maximum or minimum digital values A1 and A2, the optimum parameter β is detected to control the power level of the laser.

However, the conventional optimum laser recording power detecting apparatus uses the A / D conversion unit 5 to detect the optimum parameter β and the A / D to obtain the highest or lowest digital values A1 and A2. Since the conversion section 5 needs to change an arbitrary channel in a short time, the A / D conversion section 5 needs to operate at high speed. Accordingly, in order to develop into a high-speed recording device, an increase in a system added thereto is required. As a result, there was a problem that increases the price of the product.

Therefore, in order to solve such a problem, the present invention constructs a digital logic circuit for detecting an optimal parameter β from an RF signal of the laser reflection amount by irradiating a laser on the disk surface in a recordable optical disk, The purpose is to reduce the price of the product by simply detecting the optimum parameter (β) in the RF signal waveform according to the time difference between phases.

The configuration and operation of the present invention optimized laser recording power detection apparatus for achieving the above object will be described with reference to FIG.

First, a square wave switching unit 11 for converting an RF signal inputted in an up-down asymmetrical form into an asymmetrical square wave according to a predetermined section, and outputting it, a high frequency oscillating unit 12 for oscillating a high frequency, and a square wave switching unit ( A high section counter 13 for counting and outputting a clock of a high frequency oscillated by the high frequency oscillation unit 12 when the asymmetric RF signal square wave converted and outputted at 11) is a high section; The first comparator 14 and the first comparator 14 for comparing the clock of the high frequency counted by the interval counter 13 and the magnitude of the predetermined register value output from the first register 15. The first switch SW11 is switched to select the high frequency clock of the high section counter 13 or the constant register value of the first register unit 15 according to the comparison with the first switch SW11 and the first switch while outputting the constant register value. The first register unit 15 for storing the comparison value of the selected first comparison unit 14 according to the switching operation of the value SW11 and the asymmetric RF signal square wave converted and output from the square wave switching unit 11 are In the case of a low section, a low section counter section 16 for counting and outputting a high frequency clock oscillated by the high frequency oscillator 12, and a high frequency clock counted and output from the low section counter section 16; And the high frequency clock of the row section counter 16 according to the comparison between the second comparator 17 and the second comparator 17 comparing the magnitudes of the predetermined register values output from the second register 18 with the second comparator 17. Alternatively, a second switch SW12 for switching to select a constant register value of the second register unit 18 and a second comparator selected according to the switching operation of the second switch SW12 while outputting a constant register value. A second register for storing the comparison value of 17) And section 18, is configured with a microcomputer 19 for controlling the power level of the laser according to the first and second predetermined comparison value stored in the register section 15 (18).

The operation of the inventive laser recording power detection device configured as described above will be described below.

First, as shown in FIG. 4 (a), when the RF signal inputted in the up-down asymmetrical form is input to the system, the square wave switching unit 11 receives the RF signal inputted in the up-down-symmetrical form. According to the section (high or low), as shown in FIG. 4 (b), the high frequency counter 13 or the low section counter 16 is outputted while switching to the asymmetric square wave.

At this time, while the high frequency clock oscillated by the high frequency oscillation unit 12 is input to the high and low section counter units 13 and 16, the asymmetric RF signal square wave of the asymmetric type RF signal generated by switching to the square wave switching unit 11 is high ( HIGH), the high section counter 13 starts counting the high frequency clock oscillated by the high frequency oscillator 12 as shown in FIG. 4 (c) and outputs it to the first comparator 14. .

The first comparison unit 14 compares the high frequency clock counted by the high section counter 13 and the magnitude of a predetermined register value output from the first register unit 15, and compares the magnitudes. The switching operation of the first switch SW11 is controlled while using one value as a constant control signal.

That is, in the first switch SW11, the constant register value output from the first register unit 15 is counted and output from the high section counter 13 according to the constant control signal used by the first comparator 14. If it is greater than the clock of the high frequency, the first register 15 performs a selective control switching operation so as to store the constant register value again.

In addition, when the clock of the high frequency which is counted by the high section counter 13 and outputted is larger than a predetermined register value that is output by the first register 15, the first switch SW11 uses the first register 15. ) Select control switching operation to store the high frequency clock counted by the high section counter 13.

On the other hand, while the high frequency clock oscillated by the high frequency oscillation unit 12 is input to the high and low section counter units 13 and 16, the asymmetric RF signal square wave of the asymmetric type RF signal that is switched and output by the square wave switching unit 11 is low ( LOW), the low section counter 16 starts to count the clock of the high frequency oscillated by the high frequency oscillator 12 as shown in FIG. 4 (d) and outputs it to the second comparator 17. .

The second comparator 17 compares the high frequency clock counted by the row section counter 16 and the predetermined register value output from the second register 18, and compares the magnitudes. The switching operation of the second switch SW12 is controlled while using one value as a constant control signal.

That is, in the second switch SW12, the constant register value output from the second register unit 18 is counted and output from the low section counter unit 16 according to the constant control signal used by the second comparison unit 17. If it is larger than the clock of the high frequency, the second register unit 18 performs the selection control switching operation so as to store the constant register value again.

In addition, when the clock of the high frequency which is output by counting in the row section counter section 16 is larger than a predetermined register value output by the second register section 18, the second register section 18 in the second switch SW12. The select control switching operation is performed to store the high frequency clock counted by the low section counter unit 16).

Therefore, the microcomputer 19 controls the power level of the laser according to a predetermined comparison value stored in the first and second register units 15 and 18.

That is, when the constant comparison value stored in the first register unit 15 is greater than the constant comparison value stored in the second register unit 18, the microcomputer 19 sets the constant comparison value of the first register unit 15 to a first comparison value. The control operation is performed to lower the power level of the laser so as to be equal to a constant comparison value of the two register units 18.

On the contrary, if the constant comparison value stored in the first register unit 15 is smaller than the constant comparison value stored in the second register unit 18, the microcomputer 19 compares the constant comparison value of the first register unit 15. The control operation is performed to increase the power level of the laser so as to be equal to the constant comparison value of the second register unit 18.

As described above, the present invention constructs a digital logic circuit for detecting the optimal parameter β from the RF signal of the laser reflection amount by irradiating the laser on the disk surface on the recordable optical disk, It is possible to reduce the price of the product by simply detecting the optimum parameter (β) in the RF signal waveform according to the time difference.

Claims (1)

A laser recording power detection apparatus for controlling an optical laser disk to have an optimum laser output from an RF laser signal reflected from a disk surface, wherein the RF signal inputted in an up-down asymmetric form is converted into a square wave of up-down asymmetry according to a predetermined section. A square wave switching unit for outputting, a high frequency oscillating unit for oscillating a high frequency signal, a counter unit for counting and outputting a clock for each of the high and low sections of the square wave switching unit, a register unit for storing a predetermined value, and A comparison unit for comparing the number of clocks counted and outputted from the counter unit with a predetermined register value output from the register unit, and outputting a large value, and outputting the counter unit or a constant register value of the register unit according to the determination of the comparison unit. A switch operable to be stored and stored And a microcomputer for controlling the laser recording power according to the value stored in the register, wherein the register unit, the comparison unit, and the switch are provided separately for each of the high and low sections of the square wave output from the square wave switching unit. And a register unit stores a value determined as a large value in the comparison unit, and the microcomputer issues an output enhancement or output reduction command such that the values stored in the register are the same.