JP2006216154A - Optical information recording and reproducing device, and recording pulse adjusting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems, wherein in the recording pulse setting of the conventional 2T multi-pulse, it is necessary to decide setting value, in advance, or to detect the phase error quantity of each mark to make adjustment for each mark, a large memory capacity is required, it takes a long time for adjustment, and it takes a time before the start of recording. <P>SOLUTION: Phase error detection of the mark is divided into even number mark groups of 3T, 4T, 5T, and 6T or more, and even number mark groups of 7T or more, an optimum recording pulse string is realized, by adjusting the top pulse and the last pulse by odd and even numbered groups, on the basis of average phase error quantity of these groups, and high definition mark formation can be realized. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical information recording / reproducing apparatus and a recording pulse adjusting method for recording information on an optical recording medium.

  In recent years, an optical information recording / reproducing apparatus, particularly an optical recording apparatus that records a large amount of digital data at a high speed has attracted attention.

  For example, a phase-change optical disk medium is heated and melted by irradiation with a light beam, and then amorphized by rapidly cooling or crystallized by gradually cooling. Usually, the amorphized part has a low reflectivity and the crystallized part has a high reflectivity. Therefore, the amorphized part is called a mark, and the crystallized part is called a space.

  When recording information, a desired mark length is formed by a recording pulse train that repeats a series of recording pulses that are irradiated with a light pulse with a high intensity after irradiation with a light pulse with a high intensity, and a medium intensity light is continuously applied. The desired space length is formed by irradiating, but since the space portion other than the mark portion becomes a space portion, it may be considered that information is generally recorded by forming a mark.

  In the case of high-speed recording, the width of the light pulse with a high intensity of the recording pulse or the light pulse with a low intensity becomes too narrow, making it difficult for an actual optical information recording / reproducing apparatus to output this thin pulse. The problem that it becomes impossible.

  In order to solve this problem, for example, Patent Document 1 shows a method of making a recording pulse repetition period longer than a reference clock period.

  3 and 4 show the waveforms of the recording pulse train used to form marks having various lengths. For example, when information is recorded, the information is converted into a recording modulation code from 3T to 11T by a modulation method and recorded by marks and spaces from 3T to 11T.

  FIG. 3 shows a recording pulse train for recording a 7T mark. A recording pulse (hereinafter referred to as a top pulse) 25 at the beginning of a recording data waveform which is a recording modulation code is a light pulse (hereinafter referred to as a peak pulse) 23 having a high recording power Pp and a recording power having a low intensity. The recording pulse is composed of a Pb light pulse (hereinafter referred to as a cooling pulse) 24. Similarly, the end recording pulse (hereinafter referred to as the last pulse) 27 and the recording pulse (hereinafter referred to as the middle pulse) 26 between the top pulse and the last pulse are also composed of a peak pulse and a cooling pulse.

  The position and width of the top pulse 25 are represented by the time dTtp from the reference A at the start end position of the top pulse 23, and the width is represented by Ttop. Similarly, the start and width of the middle pulse and the last pulse are represented by times dTmp, Tmp, dTlp, and Tlp from B and C, which are the respective references. In the last pulse, the end of the cooling pulse is represented by Tcp.

  In this way, the period of each recording pulse is generated at a period of 2T with respect to the period T of the reference clock to form a mark. A space part is produced | generated by irradiating medium light intensity Pe.

  FIG. 4 shows a recording pulse train from 3T to 11T. The recording pulse shown in FIG. 4 has a recording pulse period of 2T, the recording pulse forming the 3T mark is composed of one recording pulse of the top pulse, and the recording pulses forming the 4T and 5T marks are 2 pulses of the top pulse and the last pulse. It consists of two recording pulses. A recording pulse for forming a mark of 6T or more includes a top pulse, a last pulse, and a middle pulse in between.

  In addition, the optical information recording / reproducing apparatus may vary greatly from apparatus to apparatus, and a mark cannot be recorded with high quality unless the position and width of each recording pulse are adjusted for each apparatus. Therefore, in the prior art, there is a method of detecting the recording position of each mark and adjusting the recording pulse position as disclosed in Patent Document 2, for example.

  Hereinafter, a conventional recording pulse position adjusting method will be described with reference to FIGS. 2 and 5 to 7.

  FIG. 5 shows the recording area arrangement of an optical disk as an optical recording medium. The optical disc 1 is provided with a recording condition learning area 22 such as light intensity at the inner periphery of a data area 21 for recording information. In this learning area 22, trial writing is performed with a predetermined recording pulse train in order to form optimum power and optimum marks, and the recorded state of each mark is detected by reproducing the portion.

  FIG. 2 shows a configuration of an optical disc apparatus which is an optical information recording / reproducing apparatus according to the prior art. An optical disc 1 which is an optical recording medium, a laser diode (hereinafter referred to as LD (Laser)) which irradiates the optical disc 1 with a light beam. 2), a laser drive circuit 3 for driving the LD in the pick 2, a laser output control circuit 4 for instructing a desired laser output to the laser drive circuit 3, and the optical disc 1 Is a spindle motor 5 that rotates to a predetermined linear velocity, a reproduction clock generation circuit 10 that includes a PLL (Phase Locked Loop) circuit that generates a reproduction clock based on a signal recorded on the optical disk 1, and the like. By reproducing the test writing signal recorded in the recording condition learning area 22, the start and end of each mark, the reproduction clock, A phase error detection circuit 6 that detects a phase error amount that is a deviation amount, and calculates the position and width of a recording pulse for forming an optimum mark length from the phase error amount of each mark length detected from the phase error detection circuit 6 The optimum recording pulse determining circuit 7 to determine the recording of each mark by forming an optimum mark on the basis of the clock generated by the reference clock generating circuit 9 based on the information sent from the optimum recording pattern generating circuit 7 It comprises a recording pulse train generation circuit 8 that generates pulses.

  The test writing data recorded in the recording condition learning area 22 under a predetermined condition is reproduced, and the phase error detection circuit 6 detects the phase error of each mark. For example, the phase error amounts at the front end and rear end of each mark from 3T to 11T as shown in FIG. 6 are detected. Among these phase error amounts, for example, when the value of the phase error amount d6e at the end of the 6T mark is large, the optimum recording pulse determination circuit 7 adjusts the 6d mark last pulse position and width, 6dTtp, 6Ttop, and 6Tcl. The amount is determined, and the command is issued to the recording pulse train generation circuit 8. The recording pulse train generation circuit 8 generates a recording pulse train in which the position and width of the last pulse for forming the 6T mark are adjusted so that the 6T mark is normally formed.

As shown in FIG. 7, the optimum recording pulse determination circuit 7 adjusts the position and width of the top pulse from 3T to 11T, the last pulse from 4T to 11T, and the middle pulse from 5T to 11T as shown in FIG. A memory for storing the amount is provided, and an adjustment amount for optimally forming each mark is calculated and determined from the detection amount of the phase error detection circuit 6.
JP 2004-171735 A JP 2003-30837 A

  In such an optical information recording / reproducing apparatus, in order to form a high-quality mark with respect to variations in recording characteristics for each drive, the mark start and end at each mark length are detected, and the start pulse of the recording pulse train for each mark and In order to adjust the position and width of the end pulse, in order to perform calculation for obtaining the recording pulse position and width for forming each mark based on the memory for storing the phase error amount of each mark length and the phase error amount of each mark It had the problem of taking time.

  The present invention reduces the amount of mark start and end position detection when recording using a recording pulse every nT periods of a reference clock, and adjusts the recording pulse position and width to be adjusted in grouped units, thereby The purpose is to reduce the amount, reduce the calculation time, and shorten the optimum recording pulse learning time.

  In order to solve this problem, the present invention provides optical information for recording information by forming a mark having a mark length nT (n is an integer of 1 or more) that is an integral multiple of the period T of the reference clock at a predetermined linear velocity. A recording / reproducing apparatus, for forming a mark, a recording pulse generating means for generating a recording pulse every recording pulse generation period mT (m is an integer of 2 or more) which is an integral multiple of a reference clock period T; A recording mark detecting means for detecting a recording state; and a recording pulse adjusting means for adjusting a recording pulse generated by the recording pulse generating means based on the recording state detected by the recording mark detecting means. The means includes a mark having two or less recording pulses as the first mark group, a mark having three or more recording pulses as the second mark group, and the first mark group. For the second mark group, the position and width of each recording pulse are individually adjusted, and for the second mark group, the mark length nT is subdivided into m groups according to the number of remainders divided by the recording pulse generation period mT. Within the group, the positions and widths of the front end pulse, rear end pulse and other intermediate pulses among the three or more recording pulses are adjusted to be the same, and the recording mark detection means The recording state of each mark is detected, and for the second mark group, the average value of the recording state of the mark is detected for each subdivided group.

  The present invention is also an information recording method for recording information by forming a mark having a mark length nT (n is an integer of 1 or more) which is an integral multiple of the period T of the reference clock at a predetermined linear velocity. In order to form the first mark group, a recording pulse is generated every recording pulse generation period mT (m is an integer of 2 or more) which is an integral multiple of the period T of the reference clock, and the number of recording pulses is two or less. The second mark group is divided into three or more second mark groups. In the first mark group, the position and width of each recording pulse can be individually changed. In the second mark group, the mark length nT is set to the recording pulse generation period mT. Subdivided into m groups according to the number of remainders divided by, and within the subdivided groups, the front end pulse, the rear end pulse, and other intermediates among three or more recording pulses A recording pulse generation step for making the position and width of the pulses the same, and at least a recording state of each mark of the first mark group and an average recording state of the mark for each subdivided group of the second mark group A recording mark detection step and a recording pulse adjustment step for adjusting a recording pulse so as to optimally form a recording mark based on the recording state detected in the recording mark detection step are provided.

  According to the optical information recording / reproducing apparatus and recording pulse adjusting method of the present invention, when a mark is formed with a recording pulse train having a recording pulse generation period mT, the mark start / end detection amount, the recording pulse train start / end position and width are adjusted. The amount can be reduced, and the effect of speeding up the optimum recording pulse learning can be obtained.

  Further, by shortening the optimum recording pulse learning time, it is possible to shorten the time required to start recording by the optical information recording / reproducing apparatus, thereby improving the system performance.

(Embodiment 1)
FIG. 1 shows an embodiment of an optical information recording / reproducing apparatus according to the present invention. Reference numeral 1 denotes an optical disk as an optical recording medium. A recording condition learning area such as light intensity is provided in the inner periphery of a data area for recording information. Is provided. In this recording condition learning area, for example, a trial writing signal converted into a signal from 3T to 11T with respect to the reference clock period T is trial-written with a predetermined recording pulse train to form an optimum power and an optimum mark length. The recording state is detected by reproducing each mark formed by the recording pulse train. Reference numeral 2 denotes a pick equipped with an LD for irradiating the optical disk 1 with a light beam, 3 denotes a laser drive circuit for driving the LD in the pick 2, and 4 designates a desired laser output to the laser drive circuit 3. A laser output control circuit 5 is a spindle motor that keeps a linear velocity at the time of recording information on the optical disc 1, and 11, 12, 13, 14, and 15 are recording mark detection means, respectively, and the recording condition learning area 3T mark phase which detects the phase error amount which is the amount of deviation between the start and end of odd marks of 3T, 4T, 5T and 6T or higher and odd marks of 7T or higher and the reproduction clock by reproducing the test writing signal recorded in Error detection circuit 11, 4T mark phase error detection circuit 12, 5T mark phase error detection circuit 13, even mark phase error detection circuit 14, odd mark phase error Output circuits 15 and 7 are recording pulse adjusting means for determining the position and width of the recording pulse train so as to form an optimal recording mark based on the phase error detected by the phase error detection circuit for each mark. Reference numeral 9 denotes a reference clock generation circuit for generating a reference clock for recording the recording data as a recording pulse. Reference numerals 16, 17, 18, 19, and 20 denote recording pulse generation means for adjusting each mark of the optimum recording pulse determination circuit 7. 3T mark recording pulse generating circuit 16, 4T recording pulse train generating circuit 17, and 5T recording pulse train for generating recording pulses of 3T, 4T, and 5T, an even mark of 6T or more, and an odd mark of 7T or more based on the quantity. A generation circuit 18, an even recording pulse train generation circuit 19, and an odd recording pulse train generation circuit 20.

  The optical information recording / reproducing apparatus configured as described above will be described below with reference to FIGS. 1 and 8 to 10 together with the recording pulse adjusting method of the present invention.

In the case of recording information at high speed, there is a method in which the repetition cycle of the recording pulse used for forming the mark is made longer than the reference clock cycle as described in the background art.
When a mark having an nT (n is an integer of 1 or more) length is formed, the mark may be formed by using a recording pulse train in which recording pulses are generated with a period of mT (m is an integer of 2 or more). In particular, in the case of m = 2, each mark is divided into an odd number and an even number, and there is a feature that the case of the recording pulse is easy.

  First, a test writing pattern is recorded in the recording condition learning area under an initial condition predetermined in the recording condition learning area. In order to detect the recording quality of each recorded mark, the 3T mark phase error detection circuit 11, the 4T mark phase error detection circuit 12, and the 5T mark phase error detection circuit 13 convert the phase error between the front end and the rear end from 3T to 5T mark. To detect. An even mark phase error detection circuit 14 and an odd mark phase error detection circuit 15 detect the average error amount of even marks of 6T or more and the average error amount of odd marks of 7T or more, respectively. For example, the average error amount can be easily obtained by dividing the sum of the phase error amounts at the front ends of even marks of 6T or more by the number of detections. The optimum recording pulse determination circuit 7 manages these detected phase error amounts using the phase error detection table shown in FIG. 8, and determines which mark phase error of the recorded test writing pattern is large. For example, when the phase error dEVs of the even mark of 6T or more is large, the optimum recording pulse determination circuit 7 adjusts the top pulse position and the top pulse width of the even mark of 6T or more to adjust the phase of the front end of the even mark of 6T or more. Adjust to reduce the error. FIG. 9 shows an example of a recording pulse adjustment table of the optimum recording pulse determination circuit 7. The recording pulse adjustment table indicates the position and width of the recording pulse for forming each mark. In order to adjust the even top pulse position and the top pulse width of 6T or more, the values of EVdTtp and EVTtop are adjusted.

  The recording pulse positions and widths of the 3T mark, 4T mark, and 5T mark determined as the optimum recording pulse after adjustment are set to the 3T recording pulse train generation circuit 16, the 4T recording pulse train generation circuit 17, and the 5T recording pulse train generation circuit 18, respectively. The recording pulse position and width of the even mark above the mark are transmitted to the even recording pulse train generating circuit 19 and the recording pulse position and width of the even mark above the 7T mark are transmitted to the odd recording pulse train generating circuit 20 to generate a recording pulse train forming each mark. . These recording pulse trains are sent to the laser driving circuit 3 and irradiated to the recording condition learning area on the optical disc 1 through the pick 2 to form marks.

  Again, the phase error amount of each mark is detected, and the optimum recording pulse determining circuit 7 calculates and determines the adjustment amount of the position and width of each recording pulse at which the optimum mark is formed. If the adjustment amount is smaller than a predetermined allowable value, the recording pulse is finally determined as the recording pulse that can form the optimum recording mark.

  In the multi-pulse, when the start and end positions of the mark are optimized by adjusting the top pulse and the last pulse, the same position and width of the middle pulse are set for a mark of 6T or more. There is no problem. In this case, the middle pulse position adjustment amounts EVdTmp and ODdTmp and EVTmp and ODTmp in FIG. 9 have the same value, and the memory can be shared.

  In addition, when there is little thermal interference with the recording medium, it is not necessary to adjust the recording pulse position and width so closely, and it is possible to record with sufficient quality by adjusting only the position and width of either the top pulse or the last pulse. In this case, the top pulse position adjustment amounts EVdTtp and ODdTtp and EVTtp and ODTtp shown in FIG. Can be made the same value, and further memory can be shared.

  In the above description, the recording pulse is generated in the 2T cycle. However, even when the recording pulse is generated in the 3T cycle, the recording pulse is only the top pulse and the top pulse and the last pulse are two cases. Phase error of each mark for each detailed group divided into groups of recording pulse trains consisting of top pulse, last pulse and one or more multi-pulse trains, and regrouped by the number of remainders obtained by dividing each mark length (nT) by 3 Needless to say, the optimum recording quality at each mark length can be obtained by detecting optimum recording pulse position and width based on the phase error amount and setting the recording pulse position and width.

  Needless to say, an optimum recording mark can be realized by a similar method even when a recording pulse is generated at a cycle of 3T or more.

  In the optical information recording / reproducing apparatus and recording pulse adjusting method of the present invention, when a mark is formed by generating a recording pulse with a period of 2T or more, recording is performed by grouping the recording marks having three or more recording pulses. The phase error and error amount can be calculated and the amount of memory can be reduced, and the determination time of the optimum recording pulse can be shortened, which is effective in shortening the recording start time of the optical information recording / reproducing apparatus.

The block diagram which shows the optical information recording / reproducing apparatus by the form of one Example of this invention Block diagram showing a conventional optical information recording / reproducing apparatus Explanatory drawing which shows the recording pulse position and width | variety of 7T mark of 2T period Explanatory drawing which shows each mark length formation recording pulse train of 2T period Explanatory drawing which shows the recording condition learning area of an optical disk Explanatory diagram of a phase error detection table according to the prior art Explanatory diagram of a recording pulse adjustment table according to the prior art Explanatory drawing of the phase error detection table by the form of one Example of this invention Explanatory drawing of the recording pulse adjustment table by the form of one Example of this invention Explanatory drawing of the recording pulse adjustment method by the form of one Example of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical disk 2 Pick 3 Laser drive circuit 4 Laser output control circuit 5 Spindle motor 6 Phase error detection circuit 7 Optimal recording pulse determination circuit 8 Recording pulse train generation circuit 9 Reference clock generation circuit 10 Reproduction clock generation circuit 11 3T mark phase error detection circuit 12 4T mark phase error detection circuit 13 5T mark phase error detection circuit 14 Even mark phase error detection circuit 15 Odd mark phase error detection circuit 16 3T mark recording pulse generation circuit 17 4T mark recording pulse train generation circuit 18 5T mark recording pulse train generation circuit 19 Even Mark recording pulse train generation circuit 20 Odd mark recording pulse train generation circuit 21 Data area 22 Recording condition learning area 23 Light pulse part with high intensity 24 Light pulse part with low intensity 25 Top pulse 26 Multi pulse 27 Last pulse

Claims (6)

An optical information recording / reproducing apparatus for recording information by forming a mark having a mark length nT (n is an integer of 1 or more) which is an integral multiple of a reference clock period T at a predetermined linear velocity,
Recording pulse generating means for generating a recording pulse every recording pulse generation period mT (m is an integer of 2 or more) which is an integral multiple of the period T of the reference clock in order to form the mark;
Recording mark detection means for detecting the recording state of the mark;
A recording pulse adjusting means for adjusting a recording pulse generated by the recording pulse generating means based on the recording state detected by the recording mark detecting means;
The recording pulse adjusting means sets a mark having two or less recording pulses as a first mark group, a mark having three or more recording pulses as a second mark group, and the first mark group. For the second mark group, the position and width of each recording pulse are individually adjusted. For the second mark group, the mark length nT is subdivided into m groups according to the remainder obtained by dividing the recording pulse generation period mT. Within the subdivided group, the position and width of the front end pulse, rear end pulse and other intermediate pulses among the three or more recording pulses are adjusted to be the same,
The recording mark detection means detects the recording state of each mark for the first mark group, and detects the average value of the recording state of the mark for each subdivided group for the second mark group. Information recording / reproducing apparatus. 2. The optical information recording / reproducing apparatus according to claim 1, wherein the recording pulse generating means makes the position and width of the intermediate pulse of the recording pulse of the second mark group the same. 3. The recording pulse generation means, wherein the position and width of the front end pulse and the position and width of the rear end pulse of the recording pulse of the second mark group are the same. 2. An optical information recording / reproducing apparatus according to 1. The optical information recording / reproducing apparatus according to claim 1, wherein the recording pulse generation period is 2T. 5. The optical information recording / reproducing apparatus according to claim 1, wherein the recording mark detection means detects a phase shift amount between a front end and a rear end of each mark and a reproduction clock at a predetermined reproduction speed. An information recording method for recording information by forming a mark having a mark length nT (n is an integer of 1 or more) which is an integral multiple of a reference clock period T at a predetermined linear velocity,
In order to form the mark, a recording pulse is generated every recording pulse generation period mT (m is an integer of 2 or more) that is an integral multiple of the period T of the reference clock, and the number of recording pulses is two or less. It is divided into one mark group and two or more second mark groups. In the first mark group, the position and width of each recording pulse can be individually changed. In the second mark group, the mark length nT is set to According to the number of remainders divided by the recording pulse generation period mT, it is subdivided into m groups. Within the subdivided group, the front end pulse, rear end pulse, and other intermediate pulses among three or more recording pulses are included. A recording pulse generating step for making the position and width the same;
A recording mark detection step of detecting at least the recording state of each mark of the first mark group and the average recording state of the mark for each subdivided group of the second mark group;
A recording pulse adjustment method comprising a recording pulse adjustment step of adjusting a recording pulse so that a recording mark can be optimally formed based on the recording state detected in the recording mark detection step.

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