JP2000222733A - Information recording method, information recording medium and information recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain the accurate recording to improve the density by recording the information on a recording medium while changing four power levels to the varous values. SOLUTION: A Peak Power is assigned to a 1st group, and a Bias power (1), Bias Power (2) and Bias Power (3) are assigned to a 2nd group. The independent variable to be assigned to the 1st group is designated as 'magnification x', and the independent variable to be assigned to the 2nd group is designated as 'magnification y'. The value of the Peak Power at the time of recording is made to x times of the initial value, and values of the Bias Power (1), Bias Power (2) and Bias Power (3) at the time of recording are respectively made to y times of the initial values, then the information is recorded while changing the x and y to the various values, and also the recorded information is reproduced. The fluctuation of the reproduced signal (reproduction jitter) is measured, and the values of x and y are adjusted so that the value of the measured jitter is reduced lower than the prescribed value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording method, an information recording medium, and an information recording apparatus using a recording medium on which information can be recorded by irradiating an energy beam. The present invention relates to an information recording method, an information recording medium, and an information recording apparatus using the information recording method.

[0002]

2. Description of the Related Art Conventional recording on a rewritable recording film
The erasing method may be, for example, a method using a magneto-optical disk having a recording film of an exchange-coupling two-layer film as disclosed in Japanese Patent Application Laid-Open No. Sho 62-175948, or a method disclosed in Japanese Patent Application Laid-Open No. Sho 62-25922.
In the case of using a phase-change optical disc recording film capable of high-speed erasing, which can be crystallized in almost the same time as the laser irradiation time for recording as shown in Japanese Patent Application Laid-Open No. 9-205, This has been done by varying the power level of one energy beam between at least two high power levels (ie, at least a high power level and an intermediate power level). This method has an advantage that so-called overwriting (rewriting by overwriting) in which new information is recorded while erasing existing information is possible. In addition, Japanese Unexamined Patent Publication
As described in JP-A-259229 and JP-A-3-185629, an energy beam is transmitted between three power levels, a high power level, an intermediate power level, and a lower power level than the intermediate power level. By changing it, it is possible to suppress the phenomenon that the recording mark becomes teardrop-shaped (the rear of the recording mark becomes wider than the front).

Recently, a phase change material of 120 m has been used.
D that realizes a storage capacity of 2.6 GB on one side with a disk of m diameter
VD-RAM has been put to practical use. The recording control method adopted here is based on the JIS standard 120 mm DVDRwr.
table Disk (DVD-RAM) JISX62
43 (hereinafter referred to as "Standards JIS X 6243") on page 86. This standard describes control using the above three power levels.

[0004] At present, research on increasing the density of a rewritable digital video disk (DVD-RAM) using a phase-change recording film is in progress. In an optical disk device that performs mark edge recording on a phase change recording film, such as a DVD-RAM, in order to prevent mark shape distortion and unerased portions, the outer edge of the region where the recording film is melted to form a recording mark on the recording film. In any part of the section, it is necessary that the ultimate temperature and the cooling rate during recording be almost the same. However, various recording waveforms known so far cannot sufficiently satisfy such a condition, and there is a limit to a achievable recording density. In addition, the recording characteristics of the recording medium are usually different depending on the manufacturer, the production period, and the lot of the recording medium. As the recording density is increased, it is more difficult to ensure the compatibility in the recording. Tended to be.

[0005] In particular, 4.7, which is higher density than 2.6 GB
In a DVD-RAM having a recording capacity of GB, recording with the same spot diameter as 2.6 GB facilitates compatibility with 2.6 GB. However, when the linear density is reduced with the same spot diameter, the interval between the positions where two adjacent recording pulses are irradiated on the recording medium becomes smaller than the light spot diameter of the laser light on the recording medium. Therefore, since the light distribution overlaps when the light distribution is 2.6 GB, it is necessary to prevent the recording mark shape distortion caused by the overlap. To this end, it is conceivable to use more complicatedly modulated recording waveform control, such as increasing the power level and changing the energy beam between the four power levels. With such a complicated recording waveform, a recording mark having a good shape can be formed as long as appropriate settings are made. However, as the number of energy levels increases, a problem arises as to how to optimize each energy level. In other words, when each energy level is set appropriately, a good recording mark with little recording mark shape distortion can be formed, but the energy balance becomes delicate and the energy level is increased. (1).

Further, the above-mentioned standard JIS X 6243
In the conventional recording / erasing method for a rewritable recording film described on page 86, the control using the above three power levels is described. It is written in the data area. The information recording device reads the recording power level written on the disc and sets the recording power level. However, the absolute value of the recording power level may change due to individual differences of the information recording device and environmental changes and aging of the information recording device. I often check and adjust. That is, Bias Power 1 and Bias Power given to the control data area
Record and reproduce a random pattern while changing Peak Power with 2 fixed, and measure the reproduction jitter. A recording power level that is a predetermined multiple of the recording power level at which the reproduction jitter value has reached a predetermined value is set as a new Peak Power. Next, a random pattern is recorded and reproduced while changing Bias Power 1, and the reproduction jitter is measured. The bias power at which the value of the reproduction jitter becomes minimum is defined as a new bias power 1.

A phase change recording medium having a diameter of 120 mm and exceeding 2.6 GB on one side (for example, 4.7 mm for a 120 mm diameter on one side)
In a DVD-RAM for realizing GB,
In some cases, high-precision information recording is performed by adaptively changing the timings of the leading portion and the ending portion of a recording pulse according to a combination of recording patterns to be recorded. It is conceivable that such timing information is recorded in the control data area on the disc, and the information recording device reads this timing information and uses it for actual recording.

[0008] The information recording apparatus does not always have the same recording characteristics. The recording characteristics change due to individual differences, aging of the information recording apparatus, and environmental changes. In some cases, recording cannot be performed. In such a case, since the reproduction jitter at the time of recording / reproduction of the random pattern becomes worse than expected, if the recording power level is determined based on the jitter of the random pattern as in the related art, an inappropriate recording The power level could be set. Then, when recording is performed at such an inappropriate recording power level, recording becomes unstable,
There is a possibility that the reliability of recording / reproducing may be reduced, for example, information already written may be erased by cross erase or the like (second problem).

Further, as described above, in particular, 2.6 GB
DVD-R with 4.7 GB recording capacity
In AM, by recording with the same spot diameter as 2.6 GB, compatibility with 2.6 GB can be easily obtained. However, when the linear density is reduced with the same spot, the interval between the positions where two adjacent recording pulses are irradiated onto the recording medium becomes smaller than the diameter of the laser beam spot on the recording medium. Therefore, the light distribution is 2.
Since the overlap occurs at 6 GB, it is necessary to prevent the recording mark shape distortion caused by the overlap. Further, when the space between the recording marks is short, a shift of the recording mark edge position of the reproduction signal waveform due to the inability to be resolved by the read light spot occurs, and it is necessary to prevent this. For this reason, the length of a mark to be written or a portion between marks (hereinafter, referred to as a “space”).
Attempts have been made to reduce the shift of the recording mark edge by changing the irradiation timing of the recording pulse according to the length of the recording pulse. However, for example, 4.7
When performing high-density recording using a phase-change medium such as a DVD-RAM having a GB recording capacity, the procedure for determining the irradiation timing of the recording pulse in detail is not always clear. (The third
Problem of).

[0010]

SUMMARY OF THE INVENTION A first object of the present invention is to solve the first problem by using the same spot diameter as that of the prior art and maintaining compatibility with the prior art. It is an object of the present invention to provide an information recording method and an information recording apparatus that enable accurate recording with improved density. In particular, a first object of the present invention is to provide an information recording method for easily and accurately determining each energy level when there are four energy levels when forming a recording mark, and an information recording method using the information recording method. It is to provide a device.

A second object of the present invention is to solve the above-mentioned second problem by preventing an inappropriate recording power level from being set as described above, thereby enabling stable recording and reproduction at all times. It is an object of the present invention to provide an information recording method and an information recording device.

A third object of the present invention is to solve the above third problem by using the same spot diameter as that of the above-mentioned prior art, and maintaining the compatibility with the prior art, and accurately increasing the density. An object of the present invention is to provide an information recording method, an information recording medium, and an information recording device that enable recording. In particular, a third object of the present invention is to provide a method for accurately measuring the irradiation timing of a recording pulse and a method for determining an appropriate irradiation timing, an information recording apparatus having the method and method for measuring the irradiation timing, and a method for determining the irradiation timing. It is an object of the present invention to provide an information recording medium in which the irradiation timing determined by using the measurement method or the determination method described above is recorded as fixed information.

[0013]

In order to solve the above-mentioned first problem, the following information recording method and information recording device may be used.

(1) The first state of the energy beam in the first state at the first power level of the energy beam.
Using a recording medium capable of entering a second state at a second power level higher than the power level of the recording medium, and moving the energy beam and the recording medium relative to each other to transfer the energy beam to the recording medium. An information recording method of recording information on the recording medium by irradiating the first state and the second state on the recording medium at a predetermined length and at a predetermined interval; When a third power level equal to or lower than the power level of the second state is provided, and when the area in the second state is formed on the recording medium, the area in the second state is formed to have a specific length. The energy beam is multi-pulsed by mixing the period of the third power level with the period of the second power level, and the energy beam is irradiated onto the recording medium.
Providing a fourth power level equal to or lower than the power level of the energy beam, and irradiating the recording medium with the energy beam at the fourth power level for a predetermined period following the last pulse of the multipulsed energy beam. And
The second power level is multiplied by x to a new second power level, the first power level is multiplied by y to a new first power level, and the third power level is y.
The fourth power level is multiplied by y to obtain a new fourth power level, and the information is stored in the recording medium while the values of the magnification x and the magnification y are variously changed. And reproducing the recorded information to obtain a reproduction signal, and adjusting the values of the magnification x and the magnification y such that the value of the reproduction jitter of the reproduction signal is equal to or less than a predetermined value. Recording method.

(2) the first state of the energy beam in the first state at the first power level of the energy beam;
Using a recording medium capable of entering a second state at a second power level higher than the power level of the recording medium, and moving the energy beam and the recording medium relative to each other to transfer the energy beam to the recording medium. An information recording method of recording information on the recording medium by irradiating the first state and the second state on the recording medium at a predetermined length and at a predetermined interval; When a third power level equal to or lower than the power level of the second state is provided, and when the area in the second state is formed on the recording medium, the area in the second state is formed to have a specific length. The energy beam is multi-pulsed by mixing the period of the third power level with the period of the second power level, and the energy beam is irradiated onto the recording medium.
Providing a fourth power level equal to or lower than the power level of the energy beam, and irradiating the recording medium with the energy beam at the fourth power level for a predetermined period following the last pulse of the multipulsed energy beam. And
The first power level is multiplied by z to a new first power level, the second power level is multiplied by z to a new second power level, and the third power level is z.
The third power level is multiplied to obtain a new third power level, the fourth power level is multiplied by z to obtain a new fourth power level, and information is recorded on the recording medium while the value of the magnification z is variously changed. An information recording method for reproducing the recorded information to obtain a reproduction signal, and adjusting a value of the magnification z so that a reproduction jitter value of the reproduction signal is equal to or less than a predetermined value.

(3) An information recording apparatus, comprising: an energy beam generator for generating an energy beam; a first power level and a second power level higher than the first power level. A power adjustment mechanism, a holding mechanism for holding a recording medium capable of being in a first state at the first power level, and a second state at the second power level, and the energy beam. A moving mechanism for relatively moving the recording medium and the recording medium; a positioning mechanism for irradiating the energy beam to a predetermined location on the recording medium; and a signal processing circuit for changing information to be recorded to a power level of the energy beam. When the power adjustment mechanism forms the area in the second state on the recording medium, the area in the second state When forming a particular length, a mix of period of the first power level equal to or lower third power level during said second power level,
The function of multi-pulsing the energy beam; and following the last pulse of the multi-pulsed energy beam, the energy beam is maintained at a fourth power level equal to or lower than the first power level for a predetermined period. A function of irradiating the recording medium, a function of setting a value obtained by multiplying the second power level by x as a new second power level, and a function of setting a value obtained by multiplying the first power level by y to a new first power level. A third power level as a new third power level, and a fourth power level y-multiplied value as a new fourth power level. The information recording apparatus sets the energy beam to the recording medium while variously changing the values of the magnification x and the magnification y. Irradiating the first state and the second state on the recording medium, and measuring a fluctuation of a reproduction signal obtained by reproducing the first state and the second state. An information recording apparatus, further comprising: a circuit; and a controller that adjusts the values of the magnification x and the magnification y such that a fluctuation value of the reproduction signal obtained by the time interval measurement circuit is equal to or less than a predetermined value. .

(4) An information recording apparatus, comprising: an energy beam generator for generating an energy beam; and a first power level and a second power level higher than the first power level. A power adjustment mechanism, a holding mechanism for holding a recording medium capable of being in a first state at the first power level, and a second state at the second power level, and the energy beam. A moving mechanism for relatively moving the recording medium and the recording medium; a positioning mechanism for irradiating the energy beam to a predetermined location on the recording medium; and a signal processing circuit for changing information to be recorded to a power level of the energy beam. When the power adjustment mechanism forms the area in the second state on the recording medium, the area in the second state is When the energy beam is formed to have a constant length, a third power level period equal to or lower than the first power level is mixed with the second power level period to multi-pulse the energy beam. Irradiating the recording medium with the energy beam at a fourth power level equal to or lower than the first power level for a predetermined period of time following the last pulse of the multi-pulsed energy beam; A function for setting a value obtained by multiplying the first power level by z times as a new first power level, a function of setting a value obtained by multiplying the second power level by z times as a new second power level, A function of setting a value obtained by multiplying the third power level by z as a new third power level, and a function of setting a value obtained by multiplying the fourth power level by z to a new fourth power level The information recording apparatus irradiates the recording medium with the energy beam while changing the value of the magnification z variously, thereby changing the first state and the second state. A time interval measuring circuit formed on a recording medium and reproducing the first state and the second state to measure a fluctuation of a reproduced signal; and a value of the fluctuation of the reproduced signal obtained by the time interval measuring circuit. An information recording device, further comprising: a controller that adjusts the value of the magnification z so that is smaller than or equal to a predetermined value.

In order to solve the second problem described above,
The following information recording method and information recording device may be used.

(1) The first state of the energy beam in the first state at the first power level of the energy beam.
Using a recording medium capable of entering the second state at a second power level higher than the power level of the recording medium, moving the energy beam and the recording medium relative to each other, and transferring the energy beam to the recording medium. While irradiating, the power level of the energy beam is changed between a plurality of power levels including the first power level and the second power level according to information to be recorded to form a pulse train of the energy beam. An information recording method for recording information on the recording medium by forming the first state and the second state on the recording medium at predetermined lengths and intervals. Is fixed to an appropriate initial value to optimize the value of the first power level, and the second power is fixed to the first power level by fixing the first power level to the optimized value. Optimizing Reberu, information recording method.

(2) the first state of the energy beam in a first state at a first power level of the energy beam;
Using a recording medium capable of entering the second state at a second power level higher than the power level of the recording medium, moving the energy beam and the recording medium relative to each other, and transferring the energy beam to the recording medium. While irradiating, the energy level is changed between a plurality of power levels including the first power level and the second power level in accordance with information to be recorded to form a pulse train of an energy beam, and An information recording method, wherein information is recorded on the recording medium by forming the first state and the second state on the recording medium at predetermined lengths and intervals.
A first timing adjustment method for adjusting a timing of a pulse of the energy beam corresponding to a head portion of the second state to be formed on the recording medium, and the second state to be formed on the recording medium And at least one of a second timing adjustment method for adjusting a timing of a pulse of the energy beam corresponding to an end portion of the power beam, and after optimizing a power level by the information recording method described in the above (1), A first adjustment procedure for adjusting the timing according to the first timing adjustment method and the second timing adjustment method, and adjusting the timing according to the first timing adjustment method and the second timing adjustment method. (1) At least one of the second adjustment procedure for optimizing the power level by the information recording method described in (1) To, information recording method.

(3) An information recording apparatus, comprising: an energy beam generator for generating an energy beam; and a first power level and a second power level higher than the first power level. A power adjustment mechanism that can be set at a first power level, a holding mechanism that holds a recording medium that can be set at a first state at the first power level, and a second state at the second power level, A moving mechanism for relatively moving a beam and the recording medium, a positioning mechanism for irradiating the energy beam to a predetermined location on the recording medium, and a signal processing for changing information to be recorded to a power level of the energy beam In the circuit and the setting of the power level at the time of recording, the second power level is fixed to an appropriate initial value and the first power level is fixed. After optimizing Le, said fixing the first power level to the optimized value second
Means for optimizing the power level of the information recording apparatus.

(4) An information recording apparatus, comprising: an energy beam generator for generating an energy beam; and a first power level and a second power level higher than the first power level. A power adjustment mechanism that can be set at a first power level, a holding mechanism that holds a recording medium that can be set at a first state at the first power level, and a second state at the second power level, A moving mechanism for relatively moving a beam and the recording medium, a positioning mechanism for irradiating the energy beam to a predetermined location on the recording medium, and a signal processing for changing information to be recorded to a power level of the energy beam A circuit and a timing of a pulse of the energy beam corresponding to a head of the second state to be formed on the recording medium. At least one of a first timing adjusting unit for adjusting the timing of a pulse of the energy beam corresponding to an end portion of the second state to be formed on the recording medium. And a third timing adjusting means for adjusting the timing in the first timing adjusting means and the second timing adjusting means after optimizing the power level by the optimizing means according to (3); 1
And / or at least one of a fourth timing adjusting unit for optimizing a power level by the optimizing unit according to the above (3) after the timing is adjusted by the timing adjusting unit and the second timing adjusting unit. Information recording device. To solve the third problem mentioned above,
The following information recording method, information recording medium and information recording device may be used.

(1) The first state of the energy beam in a first state at a first power level of the energy beam.
Using a recording medium capable of entering a second state at a second power level higher than the power level of the recording medium, and moving the energy beam and the recording medium relative to each other to transfer the energy beam to the recording medium. An information recording method of recording information on the recording medium by irradiating the first state and the second state on the recording medium at a predetermined length and at a predetermined interval. When the period of the recording timing generation clock is T and the relative speed between the energy beam and the recording medium is v, the length avT
The second state (a first mark), the first state (a first space) having a length ivT following the first mark, and the second state having a length mvT following the first space. State (second mark), the first state (second space) having a length jvT following the second mark, and the second state having a length bvT following the second space.
The first state and the second state alternately appear a finite number of times, starting from the first state and ending with the first state. A state is a second small recording pattern, a state in which the second small recording pattern appears following the first small recording pattern is a basic recording pattern, a state in which the basic recording pattern appears repeatedly is a recording pattern, The above-mentioned recording pattern comprising a basic recording pattern in which the parameter j is variously changed while fixing the parameter a, the parameter i and the parameter m is defined as a first recording pattern.
The parameters a, i, m, and j are natural numbers, and the parameter b, the parameter j, and the parameter m are fixed, and the parameter i is variously changed while the basic recording pattern is changed to the second recording. A pattern, wherein the parameter b is a natural number, and at least one of a first edge position measuring method and a second edge position measuring method is used, and the first edge position measuring method is the first edge position measuring method. It corresponds to a boundary position between the second mark and the first space in the read signal from a time corresponding to a mark edge position opposite to the first space of the first mark in the read signal of the recording pattern. The second mark and the first mark are compared by comparing the time interval until the time of
A position corresponding to a boundary position between the second mark and the second space in the read signal of the second recording pattern by estimating the position of the boundary with the space. (B + j) T
An information recording method for estimating a position of a boundary between the second mark and the second space by comparing the time interval with the second time interval.

(2) the first state of the energy beam in the first state at the first power level of the energy beam;
Using a recording medium capable of entering a second state at a second power level higher than the power level of the recording medium, and moving the energy beam and the recording medium relative to each other to transfer the energy beam to the recording medium. An information recording method for recording information on the recording medium by irradiating the first state and the second state with a predetermined length and an interval on the recording medium; Assuming that the period of a recording timing generation clock is T and the relative speed between the energy beam and the recording medium is v, the second state (first mark) having a length avT follows the first mark. The first state (first space) of length ivT, the second state (second mark) of length mvT following the first space, and jvT of length following the second mark Previous First state the second (second space) and length bvT subsequent to said second space
Of the state (third mark) as the first small recording pattern, starting from the first state and ending with the first state, the first state and the second state alternately appear finite times. A state is a second small recording pattern, a state in which the second small recording pattern appears following the first small recording pattern is a basic recording pattern, a state in which the basic recording pattern appears repeatedly is a recording pattern, The above-mentioned recording pattern comprising a basic recording pattern in which the parameter j is variously changed while fixing the parameter a, the parameter i and the parameter m is defined as a first recording pattern.
The parameters a, i, m, and j are natural numbers, and the parameter b, the parameter j, and the parameter m are fixed, and the parameter i is variously changed while the basic recording pattern is changed to the second recording. Where the parameter b is a natural number, and has at least one of a first edge position measuring method and a second edge position measuring method, wherein a first timing adjusting method and a second timing adjusting And the first edge position measuring method corresponds to a mark edge position of the read signal of the first recording pattern opposite to the first space of the first mark. The time interval from the time to the time corresponding to the boundary position between the second mark and the first space in the read signal is (a + i By comparing with the time interval of T, the position of the boundary between the second mark and the first space is estimated. A time interval from a time corresponding to a boundary position between the second mark and the second space to a time corresponding to a mark edge position of the third mark in the read signal opposite to the second space. Is compared with the time interval of (b + j) T to estimate the position of the boundary between the second mark and the second space, and the first timing adjustment method forms the position on the recording medium. Changing the timing at which the energy beam reaches the second power level according to a combination of the length of the first state and the length of the second state; The method of adjusting the timing changes the energy beam from the second power level to another energy level according to a combination of a length of the second state to be formed on the recording medium and a length of the first state. An information recording method that changes the timing of the information recording.

(3) The first state of the energy beam in the first state at the first power level of the energy beam.
Using a recording medium capable of entering a second state at a second power level higher than the power level of the recording medium, and moving the energy beam and the recording medium relative to each other to transfer the energy beam to the recording medium. A method for recording information on the recording medium by irradiating the first state and the second state on the recording medium at a predetermined length and at a predetermined interval. If the period of the recording timing generation clock is T and the relative velocity between the energy beam and the recording medium is v, the length avT
The second state (a first mark), the first state (a first space) having a length ivT following the first mark, and the second state having a length mvT following the first space. State (second mark), the first state (second space) having a length jvT following the second mark, and the second state having a length bvT following the second space.
The first state and the second state alternately appear a finite number of times, starting from the first state and ending with the first state. A state is a second small recording pattern, a state in which the second small recording pattern appears following the first small recording pattern is a basic recording pattern, a state in which the basic recording pattern appears repeatedly is a recording pattern, The above-mentioned recording pattern comprising a basic recording pattern in which the parameter j is variously changed while fixing the parameter a, the parameter i and the parameter m is defined as a first recording pattern.
The parameters a, i, m, and j are natural numbers, and the parameter b, the parameter j, and the parameter m are fixed, and the parameter i is variously changed while the basic recording pattern is changed to the second recording. The parameter b is a natural number, and at least one of the first edge position measuring method and the second edge position measuring method is used. Having at least one of
The method includes at least one of a first timing correction method and a second timing correction method, wherein the first edge position measurement method is configured to perform the first edge position measurement method based on the first mark of the first mark in the read signal of the first recording pattern. The time interval from the time corresponding to the mark edge position on the opposite side to the space corresponding to the space corresponding to the boundary position between the second mark and the first space in the read signal is defined as the time interval of (a + i) T. By performing the comparison, the position of the boundary between the second mark and the first space is estimated, and the second edge position measuring method uses the second mark in the read signal of the second recording pattern. From the time corresponding to the boundary position between the third mark and the second space, the read signal corresponds to the mark edge position of the third mark opposite to the second space. By comparing the time interval up to the time interval with the time interval of (b + j) T, the position of the boundary between the second mark and the second space is estimated, and the first timing adjustment method uses the recording method. Changing a timing at which the energy beam reaches the second power level according to a combination of a length of the first state and a length of the second state to be formed on a medium; The adjusting method changes the energy beam from the second power level to another energy level according to a combination of the length of the second state to be formed on the recording medium and the length of the first state. Changing the timing, wherein the first timing correction method adjusts the timing in the first timing adjustment method based on a result of the first edge position measurement method. And integer, the second timing correction method is to adjust the timing of the second timing adjustment method based on the results of the second edge position measuring method, an information recording method.

(4) the first state of the energy beam in the first state at the first power level of the energy beam;
Using a recording medium capable of entering a second state at a second power level higher than the power level of the recording medium, and moving the energy beam and the recording medium relative to each other to transfer the energy beam to the recording medium. An information recording method of recording information on the recording medium by irradiating the first state and the second state on the recording medium at a predetermined length and at a predetermined interval. Assuming that the period of a recording timing generation clock is T and the relative speed between the energy beam and the recording medium is v, the second state (first mark) having a length avT follows the first mark. The first state (first space) of length ivT, the second state (second mark) of length mvT following the first space, and jvT of length following the second mark Previous First state the second (second space) and length bvT subsequent to said second space
Of the state (third mark) as a first small recording pattern, starting from the first state and ending with the first state, wherein the first state and the second state are finite times A state that appears alternately is a second small recording pattern, a state in which the second small recording pattern appears following the first small recording pattern is a basic recording pattern, and a state in which the basic recording pattern appears repeatedly is a recording pattern. age,
The recording pattern consisting of the basic recording pattern in which the parameter j is variously changed while fixing the parameter a, the parameter i and the parameter m is defined as a first recording pattern, wherein the parameters a, i, m and j are: The recording pattern, which is a natural number and is composed of the basic recording pattern in which the parameter i is variously changed while fixing the parameter b, the parameter j, and the parameter m, is defined as a second recording pattern.
Is a natural number, uses at least one of the first edge position measurement method and the second edge position measurement method, has at least one of the first timing adjustment method and the second timing adjustment method, and And at least one of the second timing correction method and the first edge position measurement method, wherein the first edge position measurement method uses the first space of the first mark in the read signal of the first recording pattern. The time interval from the time corresponding to the mark edge position on the opposite side to the time corresponding to the boundary position between the second mark and the first space in the read signal is compared with the time interval of (a + i) T. Thus, the position of the boundary between the second mark and the first space is estimated, and the second edge position measurement method reads the second recording pattern. From the time corresponding to the boundary position between the second mark and the second space in the signal to the time corresponding to the mark edge position of the third mark on the read signal opposite to the second space. By comparing the time interval with the time interval of (b + j) T, the position of the boundary between the second mark and the second space is estimated, and the first timing adjustment method is performed on the recording medium. The timing for causing the energy beam to reach the second power level is changed according to a combination of the length of the first state to be formed and the length of the second state, and Determining whether the energy beam is at the second power level according to a combination of the length of the second state to be formed on the recording medium and the length of the first state. The timing for shifting to another energy level is changed, and the first timing correction method corresponds to a mark edge position on the opposite side of the first space of the first mark in the read signal of the first recording pattern. (A + a) between the time when the second signal is read and the time corresponding to the boundary position between the second mark and the first space in the read signal.
i) if the conclusion from the first edge position measurement method is that it is longer than the time interval of T, the first timing adjustment method is used to continue the first state of length iT. The second state when forming the second state with a length mT only when forming the second state with a length mT.
Hasten the timing to reach the power level of
The first signal in the read signal of the first recording pattern;
From the time corresponding to the mark edge position on the opposite side of the mark of the first space from the first space.
If it is determined from the first edge position measuring method that the time interval until the time corresponding to the boundary position between the mark and the first space is shorter than the time interval of (a + i) T, When forming the second state of length mT only when forming the second state of length mT following the first state of length iT using the first timing adjustment method The second power level is reached, and the second timing correction method is performed at a boundary position between the second mark and the second space in the read signal of the second recording pattern. The result is that the time interval from the corresponding time to the time corresponding to the mark edge position opposite to the second space of the third mark in the read signal is longer than the time interval of (b + j) T. Is obtained from the second edge position measurement method, the second state having the length mT is used to form the first state having the length jT using the second timing adjustment method. Only in such a case, delaying the timing of transition from the second power level to another energy level when forming the second state having the length mT,
And a side opposite to the second space of the third mark in the read signal from a time corresponding to a boundary position between the second mark and the second space in the read signal of the second recording pattern. If the conclusion from the second edge position measuring method is that the time interval to the time corresponding to the mark edge position is shorter than the time interval of (b + j) T, the second timing adjusting method is used. And the length jT following the second state of length mT
An information recording method, wherein only when the first state is formed, the timing for changing from the second power level to another energy level when forming the second state having the length mT is advanced.

(5) The first state of the energy beam in the first state at the first power level of the energy beam.
An information recording medium capable of entering the second state at a second power level higher than the second power level, wherein the second power level determined by using the information recording method described in (3) above. An information recording medium, wherein at least one of information of a timing to reach and information of a timing to shift from the second power level to another energy level is recorded as non-rewritable information.

(6) The first state of the energy beam in the first state at the first power level of the energy beam.
An information recording medium capable of entering the second state at a second power level higher than the second power level, wherein the second power level determined by using the information recording method according to the above (4) is An information recording medium, wherein at least one of information of a timing to reach and information of a timing to shift from the second power level to another energy level is recorded as non-rewritable information.

(7) An information recording apparatus, comprising: an energy beam generator for generating an energy beam; and a first power level and a second power level higher than the first power level. A power adjustment mechanism that can be set at a first power level, a holding mechanism that holds a recording medium that can be set at a first state at the first power level, and a second state at the second power level, A moving mechanism for relatively moving a beam and the recording medium, a positioning mechanism for irradiating the energy beam to a predetermined location on the recording medium, and a signal processing for changing information to be recorded to a power level of the energy beam And using the information recording medium according to the above (5) or (6), wherein the non-rewritable information recorded on the information recording medium is used. Means for reading out information and decoding at least one of information of timing for reaching the second power level and information of timing for transitioning from the second power level to another energy level; Means for modulating an energy pulse in accordance with the decoded timing information when forming the state of the information recording apparatus.

(8) An information recording apparatus, comprising: an energy beam generator for generating an energy beam; and a first power level and a second power level higher than the first power level. A power adjustment mechanism that can be set at a first power level, a holding mechanism that holds a recording medium that can be set at a first state at the first power level, and a second state at the second power level, A moving mechanism for relatively moving a beam and the recording medium, a positioning mechanism for irradiating the energy beam to a predetermined location on the recording medium, and a signal processing for changing information to be recorded to a power level of the energy beam A circuit, at least one of the first timing correction method and the second timing correction method according to (3), or Serial (4), means for performing at least one of the first timing correction method and the second timing correction method according comprises the information recording apparatus.

With this configuration, the number of independent variables used for adjusting the power at the time of recording can be made equal to or less than the number of power levels, the procedure for finding the optimum combination of independent variables can be simplified, and the optimum combination can be found. Reliability is also improved. Further, information can always be stably and reliably recorded on the recording medium.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail by the following embodiments.

First Embodiment First, with reference to FIG. 1, an example of a temporal change in the power level of an energy beam applied to a recording medium when information is recorded on the recording medium will be described. Here, how to change the power level over time when information is recorded is referred to as “write strategy” or “recording strategy”, and a DVD-RAM will be described as an example.

In the case of a DVD-RAM, when the time width of the reference clock in recording and reproduction is T, the length of the shortest mark and the shortest space is 3T (three times the time T). The length of the longest mark and the longest space is usually 11T. As a special pattern, there are a mark and a space having a length of 14T.

When an NRZI signal, which is information to be recorded in a time-series manner, is provided on a recording medium, the NRZI signal is converted into a time-series change in the power level of the energy beam by an appropriate signal processing circuit. Such a chronological change in the power level is shown as an optical pulse waveform in FIG.

The power levels are Peak Power, Bias Power
The power levels are set to four power levels of 1, Bias Power 2 and Bias Power 3. At Bias Power 1 (first power level), the recording medium can be shifted to the first state, and at Peak Power (second power level), the recording medium can be shifted to the second state. . Bias Pow
er3 (third power level) is a power level equal to or lower than Bias Power1. When forming the area in the second state on the recording medium, if the length of the area in the second state is 4T or more (that is, if the length of the NRZI signal is 4T or more), Peak Power Power during irradiation period
The energy beam is multi-pulsed by mixing the periods of the three power levels. The first light pulse of the multi-pulsed energy beam is called the “top pulse”,
The last light pulse is called "final pulse". Between the first pulse and the last pulse, depending on the length of the NRZI signal
An optical pulse that repeats PeakPower and Bias Power 3 is repeated. The number of repetitions is determined by the length of the NRZI signal as n.
If T (n> 3), the number is (n-4) times. The repetition pulse sandwiched between the first pulse and the last pulse is called a “comb-shaped pulse”. That is, the NRZI having a length of 5T or more
When forming a second state area corresponding to a signal,
The recording pulse includes a first pulse, a comb pulse, and a last pulse. In the case of forming an area in the second state corresponding to the NRZI signal having a length of 4T, the recording pulse includes a first pulse and a last pulse. In addition, N of 3T length
When forming an area in the second state corresponding to the RZI signal, the recording pulse is a single light pulse.

Bias Power 2 (fourth power level) whose power level is set equal to or lower than Bias Power 1 is used as follows. In an NRZI signal having a length of 4T or more, the power level following the last pulse is a predetermined time Bi
as Power 2 In the NRZI signal having a length of 3T, the power level following a single optical pulse is held at Bias Power 2 for a predetermined time.

Bias Power 1 is Bias Power 2 or Bias Pow
May be at the same power level as er3. Also, Bi
As Power 1, Bias Power 2 and Bias Power 3 may all be at the same power level. Peak Power, Bias
The reference values for Power 1, Bias Power 2 and Bias Power 3 are
In some cases, the medium information is recorded in an appropriate location on a recording medium in advance. The portion on the recording medium on which the medium information relating to the recording strategy is recorded is referred to as an “information track of the control data zone”. The power level reference value is read from the information track in the control data zone of the recording medium, and each power level at the time of writing is determined with reference to this.

First, a description will be given of the definition of a recording waveform when a region in the second state corresponding to an NRZI signal having a length of 4T or more is formed on a recording medium. The rise of the leading pulse of the write pulse train is defined by the time elapsed by T _SFP from the rise of the NRZI signal. The fall of the head pulse of the write pulse train is defined by the time that has elapsed by _TEFP from the rise of the NRZI signal. The length of the first pulse is T _FP
And the value of T _FP is equal to the value of T _{FP minus} T _SFP . The rise of the last pulse of the write pulse train is NRZI
The last pulse is defined with reference to a time preceding by a time 2T from the falling of the signal, and the last pulse is defined as a time T _SLP from this reference time.
Stand up only after elapse. The fall of the last pulse of the write pulse train also takes 2T from the fall of the NRZI signal.
The last pulse falls when the time _{TELP has} elapsed from this reference time. The length of the last pulse is T _LP , and the value of T _LP is from T _ELP to T _SLP
Is equal to the value of

In some cases, a comb-shaped pulse train exists between the first pulse and the last pulse. The rising edge of each comb pulse in the comb pulse train coincides with the reference clock position.
Each comb pulse falls when the time T _MP elapses from the rise of each comb pulse.

Next, the NRZI signal corresponding to the length 3T is supported.
A case where the area in the second state is formed on a recording medium will be described.
I will tell. Is the rising of the optical pulse the rising of the NRZI signal?
T _SFPOnly when the time has passed. Also, the light pulse
The fall precedes time 2T from the fall of the NRZI signal.
Time is defined based on the time
Time to time T_ELPThere is only when passed.

Subsequent to the last pulse after 4T or the recording pulse of 3T, there is a portion whose power level is Bias Power 2 and its length is _TLC . T _SFP , T _EFP , T _FP , T _SLP , T
The values of _ELP , T _LP , T _LC and T _MP are determined based on the reference values read from the information track in the control data zone of the recording medium.

T _SFP , which is the time for defining the recording pulse,
_{T EFP, T FP, T SLP} , T ELP, T LP, T LC and T _MP is
The value does not always take a constant value, and may need to be changed according to the combination of the NRZI signals. In particular, taking the case of a 4.7 GB DVD-RAM on one side as an example, the shortest mark length 3T is about 0.42 microns, which is shorter than the writing spot radius of 0.45 microns. When such high-density recording is performed, thermal interference between adjacent marks increases, and it may be difficult to always perform stable recording. Therefore, it is conceivable to adaptively change the recording waveform according to the combination before and after the NRZI signal.

As a method of correcting the front edge shift,
There are the following two methods. (1) to fix the T _EFP, changing the T _SFP. On this occasion,
T _FP changes with changes in T _SFP . (2) securing the T _FP, it changes the T _SFP. On this occasion,
_TEFP changes as _TSFP changes. There are the following two methods for correcting the shift of the rear edge. (1) Fix T _SLP and change _TELP . On this occasion,
T _LP changes with a change in _{TEL P.} (2) Fix T _LP and change _TELP . On this occasion,
T _SLP will change with the change of T _ELP.

Which of the above methods is selected for the shift control of the leading edge and the trailing edge depends on the design method of the recording medium and the recording characteristics of the recording medium. Which one should be selected as the shift control method of the leading edge and the trailing edge is best known by the manufacturer of the recording medium,
The manufacturer of the recording medium can recommend to the information recording apparatus which should be selected as the edge shift control method. That is, the manufacturer of the recording medium writes recommended information on the edge shift control method at a specific location on the recording medium, and the information recording device reads the recommended information to determine the edge shift control method. In this case, the information recording apparatus can utilize the medium characteristics intended by the manufacturer of the recording medium without excess, and the information can be recorded most stably. Further, the manufacturer of the recording medium prepares a look-up table for edge shift control, and records this on the recording medium. The information recording device reads the look-up table, and performs edge shift control based on the look-up table. As a result, the information recording apparatus can use the medium characteristics intended by the manufacturer of the recording medium without excess, and can record information most stably. With the above-described contrivance, it is possible to provide a means for obtaining the highest recording compatibility even with high-density recording.

The look-up table for the leading edge indicates that the length of the mark to be currently recorded is M (n).
And the length of the space preceding this mark is S (n−
In the case of 1), values determined by a combination of M (n) and S (n-1) are arranged. This value can take a positive value or a negative value.

The look-up table relating to the trailing edge indicates that when the length of a mark to be recorded at present is M (n) and the length of a space following the mark is S (n + 1), M (n) and S ( n + 1) are arranged. This value can take a positive value or a negative value.

[0048] By varying depending on the front and back of a combination of more than NRZI signals T _SFP and T _ELP as,
The mark edge position can always be controlled with high accuracy.

A mark can be formed stably by using a write strategy having four power levels at the time of recording, but this is the case when each power level is appropriately set. It is feasible to find the optimal combination of these four independent variables with four power levels as four independent variables, but the procedure is complicated and the number of steps leading to the optimal combination is enormous. Could be So by grouping the four power levels and assigning independent variables to each group,
As a result, the number of independent variables can be reduced, and the procedure for finding the optimal combination of independent variables can be simplified.

When a phase change recording medium such as a DVD-RAM is considered, Bias Power 1, Bias Power 2 and Bias Power 3 are used in the process of studying and elucidating the recording mechanism.
Levels have proven to be quite relevant. Therefore, Peak Power is assigned to the first group and Bias Power 1, Bias Power 2 and Bias Power 2 are assigned to the second group.
Assign Bias Power 3. The independent variable assigned to the first group is referred to as “magnification x (hereinafter, simply referred to as“ x ”)”, and the independent variable allocated to the second group is referred to as “magnification y (hereinafter, simply referred to as“ y ”). )) ". The Peak Power value at the time of recording is x times the initial value of Peak Power, and the Bias Power at the time of recording
1, Bias Power 2 and Bias Power 3
1, and the information is recorded while changing x and y variously with y times the initial value of Bias Power 2 and Bias Power 3, respectively.
At the same time, the recorded information is reproduced. The fluctuation (reproduction jitter) of the reproduction signal is measured, and the values of x and y are adjusted so that the measured value of the reproduction jitter becomes equal to or less than a predetermined value. By doing so, the number of independent variables can be reduced from four to two, and the procedure for finding the optimal combination of independent variables can be simplified. Further, since the procedure is simplified, the reliability of finding the optimal combination can be improved.

Another grouping is conceivable. Particularly, the procedure can be simplified by combining the four power levels into one group. That is, Peak at the time of recording
The value of Power is set to z times the initial value of Peak Power,
Set the values of Bias Power 1, Bias Power 2 and Bias Power 3 to Bi
The information was recorded while changing the magnification z (hereinafter, simply referred to as “z”) variously by setting it as z times of the initial value of as Power 1, Bias Power 2 and Bias Power 3, respectively. Play information. The fluctuation (reproduction jitter) of the reproduction signal is measured, and the value of z is adjusted so that the measured value of the reproduction jitter becomes equal to or less than a predetermined value. By doing so, the number of independent variables can be reduced from four to one, and the procedure for finding the optimal combination of independent variables can be further simplified. Further, since the procedure is further simplified, the reliability of finding the optimum combination can be further improved.

Peak Power, Bias Power 1, Bias Power 2
It is conceivable that the initial value of Bias Power 3 is determined based on the read recommended value from the information track in the control data zone of the recording medium. In this case, the power level within each group can be optimized without losing the power balance recommended by the recording medium manufacturer, so that a more compatible optimal power level for information recording can be determined. Is obtained.

Peak Power is assigned to the first group, and Bias Power 1 and Bias Power 2 are assigned to the second group.
And Bias Power 3 are assigned to obtain the appropriate values of x and y. The values of the reproduction jitter at each value of x and each value of y are obtained while randomly changing the values of x and y. There is a method of finding an appropriate value of. But x
If the proper values of x and y are obtained while systematically changing the values of y and y, the proper values may be obtained more reliably.

In the simplest case, the values of x and y are quantized at an appropriate step interval between the maximum value and the minimum value, and the values of the reproduction jitter are obtained for all combinations of the values of x and y. There is a method of obtaining a combination of x and y values at which the obtained reproduction jitter value is equal to or less than a predetermined value. This method requires a large number of times of measurement of the reproduction jitter and takes a little time, but has an effect that the proper values of x and y can be reliably obtained.

As another method for obtaining appropriate values of x and y, there is a method of sequentially performing the following first, second, and third procedures.

(1) First Procedure The value of y is set to 1. The upper limit x of x that is greater than or equal to the lower limit xs of x
By changing x with an appropriate step width dx within the range of m or less, a value x1 of x that minimizes the reproduction jitter is obtained. For example, when the lower limit xs = 0.85, the upper limit xm = 1.15, and the step width dx = 0.05, x is set to 0.85.
0.9, 0.95, 1.0, 1.05, 1.1 and 1.
By changing the value to 15, the value of the reproduction jitter at each value of x is obtained, and the value x1 of x having the smallest value of the reproduction jitter is obtained. Further, a value x2 of x at which the value of the reproduction jitter becomes the value a is obtained, and a value x3 of c times the obtained value x2 is obtained. As a specific example, data obtained by determining the value of the reproduction jitter by changing the value of x is used, and one of the values of the reproduction jitter at two adjacent values of x is larger than the value a and the other is smaller than the value a. In this case, a value x2 of x at which the value of the reproduction jitter becomes the value a is obtained from two adjacent values of x by linear interpolation. If data to be subjected to linear interpolation cannot be collected, the upper limit x of x
By increasing m and / or the lower limit value xs, data of the value of the reproduction jitter is obtained in a wider range, or the value x2 is predicted using existing data. Finally, the value x1 is compared with the value x3, and the smaller value x4 is obtained.

Here, when the point at which the reproduction jitter is minimized is obtained, the reproduction jitter does not change so much even when the value of x is changed near the appropriate value of x, and it is difficult to find the point at which the reproduction jitter is minimum. There are cases. In such a case, the following method may be used as an alternative method for finding the reproduction jitter minimum point. Since the curve of the reproduction jitter draws a parabolic curve with respect to the value of x, there are generally two values of x at which the value of the reproduction jitter takes the value a. Therefore, a small value x1L and a large value x1H among the values of x at which the value of the reproduction jitter is the value a are obtained, and an arithmetic average of the values x1L and x1H is obtained as the value x1. However, in order to find the value x1L, the value of x needs to be considerably large, and x
May be caught by the upper limit. In this case, it is difficult to apply the method using the value x1L and the value x1H.

(2) Second Procedure The value of x is set to a value x4, and y is changed with an appropriate step width dy within a range from y lower limit ys to y upper limit ym to obtain reproduction jitter. A minimum value y1 of y is obtained.
For example, the lower limit ys = 0.85 and the upper limit ym = 1.15
And step width dy = 0.05, y is 0.8
5, 0.9, 0.95, 1.0, 1.05, 1.1, and 1.15, the reproduction jitter value at each value of y is obtained, and the reproduction jitter value is the smallest y Is determined. Here, when the point at which the reproduction jitter is minimized is obtained, the reproduction jitter does not change much even when the value of y is changed near the appropriate value of y, and it is difficult to find the point at which the reproduction jitter is minimum. is there. In such a case, the following method may be used as an alternative method for finding the reproduction jitter minimum point. Since the curve of the reproduction jitter draws a parabolic curve with respect to the value of y, there are generally two y values at which the value of the reproduction jitter takes the value a. Therefore, a small value y1L and a large value y1H of the y value at which the value of the reproduction jitter is the value a are obtained, and an arithmetic average of the value y1L and the value y1H is obtained as a value y1. Either method may be used, and the value of y obtained by either method may be used as the final value y1.

(3) Third Procedure The value of y is set to a value y1. Similarly to the first procedure, x is changed with an appropriate step width dx within the range of not less than the lower limit value xs of x and not more than the upper limit value xm of x, and the value x5 of the reproduction jitter is minimized. Further, similarly to the first procedure, a value x6 of x at which the value of the reproduction jitter becomes the value a is obtained, and the obtained value x6 is obtained.
A value x7 which is c times as large as 6 is obtained. Finally, the value x5 is compared with the value x7, and the smaller value x8 of x is obtained. Here, when the point at which the reproduction jitter is minimized is obtained, the reproduction jitter does not change much even when the value of x is changed near the appropriate value of x, and it may be difficult to find the point at which the reproduction jitter is minimum. . Also in this case, the minimum point of the reproduction jitter may be found in the same manner as in the alternative method (method using the value x1L and the value x1H) described in the first procedure.

When the first, second, and third procedures described above are completed, it is determined that the appropriate value of x is the value x8 and the appropriate value of y is the value y1. X using such a first procedure, a second procedure, and a third procedure sequentially
The method of obtaining the proper values of x and y has the effect that the proper values of x and y can be obtained with the minimum number of jitter measurements.

Next, an information recording apparatus according to a first embodiment of the present invention will be described with reference to FIG. FIG. 2 is a block diagram of the information storage device according to the first embodiment of the present invention. For convenience of explanation, FIG.
0 is attached to the information storage device. The storage medium 100 is essential for storing information, but the storage medium 100 may be removed or attached to the information storage device as needed.

Referring to FIG. 2, a disk clamping mechanism 112 is mounted on a rotating shaft 111 of a motor 110 mounted on a housing 108. The chucking mechanism 112 is a storage medium 100
Holding. That is, the chucking mechanism 112 is a holding mechanism for the recording medium 100. The motor 110, the rotating shaft 111, and the chucking mechanism 112 constitute a moving mechanism for relatively moving the recording medium 100 and the energy beam.

A rail 115 is attached to the housing 108. A rail guide 116 guided by the rail 115 is attached to the case 117. A linear gear 119 is also attached to the case 117, and a rotary gear 120 is attached to the linear gear 119. By transmitting the rotation of the rotation motor 118 attached to the housing 108 to the rotation gear 120, the case 11
7 moves linearly along the rail 115. The direction of this linear motion substantially matches the radial direction of the storage medium 100.

The magnet 117 is attached to the case 117. An objective lens 136 is also attached to the case 117 via a suspension 123. The suspension 123 allows the objective lens 136 to move only in two directions, substantially the same as the normal direction of the recording surface of the recording medium 100 and substantially the same as the radial direction of the recording medium 100. The coil 122 is attached to the objective lens 136 so as to substantially face the magnet 121. Due to the magnetic force generated by passing a current through the coil 122,
The objective lens 136 can move in two directions: a direction substantially the same as the normal direction of the recording surface of the recording medium 100 and a direction substantially the same as the radial direction of the recording medium 100. Rail 115, rail guide 116, case 117, and magnet 12
1, the suspension 123, the coil 122, and the objective lens 136 constitute a positioning mechanism that irradiates a predetermined location of the storage medium 100 with the energy beam.

A semiconductor laser 131 as an energy beam generator is mounted on the case 117. The energy beam emitted from the semiconductor laser 131 is
The collimating lens 132 and the beam splitter (beam s)
plitter) 133, and then passes through an objective lens 136. Part of the light that has passed through the objective lens 136 is reflected by the storage medium 100, and then passes through the objective lens 136 and enters the beam splitter 133. Part of this light is reflected by the beam splitter 133 in the direction of the detection lens 134, is condensed by the detection lens 134, and then enters the photodetector 135, where its light intensity is detected. The photodetector 135 has a light receiving area divided into a plurality.
The light intensity detected in each light receiving area is amplified and calculated by the amplifier 152, and information (servo signal) of a relative positional relationship between the light spot collected by the objective lens 136 and the storage medium 100 is obtained. An information read signal is detected. The servo signal is sent to the servo controller 151. Further, the read signal is sent to the slicer 170 and binarized. This binarized signal is sent to the decoder 153 and the time interval measuring circuit 171.

When the storage medium 100 is attached to the information storage device and the chucking mechanism 112 fixes the storage medium 100, the detector 140 operates and sends its output signal to the system controller 150. The system controller 150 controls the motor 110 based on the output signal of the detector 140 to rotate the storage medium 100 to an appropriate rotation speed. Also, the system controller 15
0 controls the rotation motor 118 to position the case 117 at an appropriate position. In addition, the system controller 150 causes the semiconductor laser 131 to emit light, and also operates the servo controller 151 to operate the rotary motor 118 and to supply a current to the coil 123 so that the focal spot formed by the objective lens 136 is stored in the storage medium 10.
Positioning at a predetermined location of 0. After that, the servo controller 151 sends a signal to the system controller 150 that the focal spot has been formed on the storage medium 100. The system controller 150 gives an instruction to the decoder 153 and decodes a signal to be read. If the track to be read is not the information track of the control data zone, the system controller 150
An instruction is given to the servo controller 151 so that the focal spot is positioned on the information track of the control data zone. By such an operation, the system controller 150 reads the information track in the control data zone and reads the medium information related to the recording.

Information on the recording strategy described in FIG. 1 is written in the information track of the control data zone. The system controller 150 reads from the storage medium 100 the parameters of the recording strategy, such as the recording power level, the temporal relationship of each recording pulse, the look-up table, and the recommended method of adaptive control. The system controller 150 writes these recording strategy parameters in the parameter table of the signal processing circuit 154, the parameter table of the delay circuit 155, and the current sink amount parameter table of the current sink 156. Depending on the selection of the adaptive control method, the way of writing the parameter table of the delay circuit 155 is made different or the switch of the delay circuit 155 is switched.
The operation of each adaptive control method described in FIG. 1 is realized.

The system controller 150 controls the storage medium 1
00, and read them in the parameter table of the signal processing circuit 154 and the delay circuit 15.
5 and the current sink amount parameter table of the current sink 156 are stored in the storage medium 1.
00 may be in the writable state only. For example, when the write protect switch existing in the case of the storage medium 100 is set to the write-protected position, or when the higher-level controller of the information storage device instructs the write protection,
When 0 is in the write-protected state, a series of operations such as reading of parameters of the recording strategy can be omitted. A detection switch 141 is attached to the housing 108 to detect the write protection switch, and sends an output signal of the detection switch 141 to the system controller 150. When the recording is prohibited, the operation of reading the parameters of the recording strategy is stopped, and the recording medium 100 is moved to the chucking mechanism 112.
It is possible to shorten the preparation time from the time of being fixed to the state to the state of being able to be reproduced.

When an instruction to reproduce information is sent from the host controller via the input connector 159, the system controller 150 gives an instruction to the servo controller 151 to position the focal spot at an appropriate place on the storage medium 100, and After the signal obtained by the detector 135 is decoded by the slicer 170 and the decoder 153, the information read through the output connector 158 is sent to the host controller.

When an instruction to write information and information to be written are sent from the upper controller via the input connector 159, the system controller 150
An instruction is given to the servo controller 151 to position the focal spot at an appropriate location on the storage medium 100. Also,
The information to be written is converted by the signal processing circuit 161 into an NRZI signal. The NRZI signal is supplied to the signal processing circuit 154.
Is converted into a plurality of appropriate pulse trains. This pulse train passes through the delay circuit 155 and is sent to the current sink 156. Here, the signal processing circuit 161 and the signal processing circuit 154 constitute a signal processing circuit that converts information to be written into a train of recording pulses (that is, the power level of the energy beam).

A constant current source 157 is connected to the semiconductor laser 131, and the semiconductor laser 131 and the current sink 1 are connected.
The sum of the currents consumed at 56 always has a constant value. The constant current source 157 includes a plurality of current sinks 1.
56 are connected. Whether or not the current sink 156 operates to sink current depends on the pulse train generated by the signal processing circuit 154 and passed through the delay circuit 155. By operating the current sink 156, a part of the current output from the constant current source 157 is absorbed by the current sink 156, and as a result, the amount of current flowing into the semiconductor laser 131 decreases. Thereby, the energy level of the energy beam emitted by the semiconductor laser 131 is changed. The signal processing circuit 154 and the delay circuit 155 realize the recording strategy shown in FIG. 1 by operating the plurality of current sinks 156 at appropriate timing.

In order to perform the above operation, the information recording apparatus is supplied with electric power from the outside via the terminal 160.

When the necessity of information writing occurs or before the information writing occurs, the power level of the energy beam at the time of information writing may be optimized or the value of this power level may be updated. . In such a case, the system controller 150
An appropriate recording pattern is sent to the signal processing circuit 154 to form a recording mark array on the recording medium 100. After that, a reproduced signal obtained by reproducing the recording mark string is binarized by the slicer 170 and sent to the time interval measuring circuit 171. The time interval measuring circuit 171 measures the fluctuation (jitter) of the reproduction signal, and sends the measurement result to the system controller 150. The system controller 150
The recording power level is changed in accordance with the procedure described in the description of FIG. 1 based on the measurement result of the fluctuation (jitter).
The system controller 150 sends the appropriate recording pattern to the signal processing circuit 154 again, and forms a recording mark sequence on the recording medium 100 using the new recording power level. In this way, by repeating the measurement of the reproduction jitter and the updating of the recording power level accordingly, the recording power level optimal for writing to the given storage medium 100 can be created when necessary. Always stable and highly reliable information recording medium 100
The effect of being able to write is obtained.

As an example of the time interval measuring circuit 171, there is a circuit having the function of a time interval analyzer (TIA). As another example of the time interval measurement circuit 171, a digital signal binarized by the slicer 170 is subjected to PLL (Phase Lock Loop),
There is a method in which the magnitude of the L error signal (the amount of mismatch between the edge position of the clock generated by the PLL and the edge position of the binarized digital signal) is used as the amount of jitter in the binarized digital signal. . The PLL circuit is a decoder 153
It is necessary to decode the playback signal with
The use of the error signal described above has an effect that it is not necessary to implement a particularly novel TIA in the information recording device. As another example of the time interval measuring circuit 171, a digital signal binarized by the slicer 170 is compared with a recording pattern given to the signal processing circuit 154 at the time of writing, and the amount of mismatch is determined by an error pulse. As
There is a method in which the frequency of an error pulse is used to determine the amount of jitter of a binary digital signal. Also in this case, there is an effect that the amount of jitter of the binarized digital signal can be evaluated without introducing a particularly novel circuit into the information storage device.

As described above, according to the present invention, even in a high-density recording situation in which the shortest recording mark length is equal to or less than the radius of the recording spot, the recording mark edge can always be stably positioned at a predetermined position. Thus, an advantageous effect that information can always be stably and reliably recorded on the recording medium can be obtained.

(Second Embodiment) Next, an information recording method according to a second embodiment of the present invention will be described with reference to FIG.

As described above, Peak Power and Bias Power
It is conceivable that the initial values of 1, Bias Power 2 and Bias Power 3 are determined based on the recommended values read from the information tracks in the control data zone of the recording medium and read.

Here, it is assumed that a recording medium and a look-up table of a recording power level and an edge shift for the recording medium are given to the information recording apparatus. The recording power level and the look-up table may be obtained by reading a value recorded at a predetermined location on a recording medium, or may be a value obtained by an information recording apparatus by some method. The information recording apparatus performs recording using the recording power level and the look-up table. However, given that the recording temperature changes due to the environmental temperature of the information recording device changing during use or aging, the recording characteristics vary between the information recording devices, and the like. The recording power level and the look-up table may not always be optimal values for the combination of the current recording characteristics of the information recording apparatus and the recording medium. That is, consider a case where a recording power level and a look-up table cause compatibility problems due to a characteristic change over time, a characteristic difference between individual information recording apparatuses, or the like.

In the conventional phase change recording medium, when there is no look-up table of the edge shift at the time of recording, optimization of only the recording power level should be considered. Taking a single-sided 2.6 GB DVD-RAM as an example, there are various recording power level setting methods depending on the information recording device. In general, the optimum recording power level is determined by the following procedure. Is set.

(1) Bias Power 1 (2.6 GB D on one side)
The Peak Power (the name in the 2.6 GB DVD-RAM standard) is fixed and the Bias Power 2 (the name in the 2.6 GB DVD-RAM standard) is fixed to the VD-RAM standard. The random pattern is recorded and reproduced while changing, and the jitter of the reproduced signal is measured. A recording power level that is 1.2 times the recording power level at which the jitter value is 13% is set to Peak Power (a single-sided 2.6 GB DVD-
(Name in the RAM standard).

(2) Bias Power 1 (2.6 GB D on one side)
The random pattern is recorded and reproduced while changing the VD-RAM standard name), and the jitter of the reproduced signal is measured. The bias power level at which the value of the jitter is minimized is referred to as Bias Power 1 (named in a 2.6 GB single-sided DVD-RAM standard). Alternatively, the bias power level at the middle point between the two points where the jitter value crosses 13% is Bi
as Power 1 (2.6-GB single-sided DVD-RAM standard).

(3) In some cases, the above procedures (1) and (2) are performed again.

That is, the optimum recording power level can be obtained from a jitter curve of a reproduced signal by recording and reproducing a random pattern.

When recording is performed using a look-up table of an edge shift, which is higher in recording density than a single-sided 2.6 GB DVD-RAM and is not present in a single-sided 2.6 GB DVD-RAM, the above-described operation is performed. In some cases, it is not possible to set a sufficiently accurate power level by merely measuring the reproduction jitter of a random pattern. In other words, this is a case where compatibility of the edge shift lookup table itself cannot be maintained. In this case, the reproduction jitter of the random pattern as described above has a worse value than expected because the look-up table is not suitable, and the power level cannot be determined normally. In such a case, it may be desirable to set the power level without using a lookup table that is no longer compatible.

The inventor of the present application has been studying how to update the recording power level and the look-up table when the compatibility of the recording power level and the look-up table cannot be obtained. 6G
In an information recording apparatus that uses a phase change medium having an area density exceeding that of the DVD-RAM of B and performs recording control using a look-up table, the recording power level and the look-up can be accurately determined by performing the following procedure. He came to realize that the uptable could be updated.

(1) Peak Power and Bias P are determined by the repetition pattern of marks and spaces having the same length.
Set ower. Set Peak Power and Bias Power
Are called Provisional Peak Power and Provisional Bias Power, respectively. What is important here is the power level determination order and the recording pattern. It should be noted that, when simply referred to as “Bias Power”, all of Bias Power 1, Bias Power 2 and Bias Power 3 shown in FIG. 1 are indicated. (2) The look-up table is optimized using the provisional Peak Power and the provisional Bias Power. (3) Peak Power and Bias Power are set using a random pattern using an optimized look-up table. What is important here is the order of determining the power levels and the recording pattern.

In the above procedure (1), Peak Power and
There are various methods for specifically setting the bias power, but a method that is convenient for the information recording device may be selected. The important thing is that the power level setting order (Peak Power is fixed to its initial value, Bias Power is optimized,
The order of optimizing Peak Power by fixing Power to the optimal value of Bias Power) and using a repetitive pattern of marks and spaces of the same length. The necessity of such an order will be described below.

FIG. 3 shows an experimental example for determining Peak Power. The experiment was performed under the condition of a 4.7 GB DVD-RAM on one side. The horizontal axis is for Peak Power, 3T in length
The reproduced signal amplitude of the repetition pattern of the mark and the space having a length of 3T is plotted against Peak Power.
The parameters are for Bias Power 1. Where Bias
When changing Power 1, Bias Power 2 and Bias Power
3 is changed so that the ratio with Bias Power 1 becomes constant. If Peak Power is determined from such an experiment, Pe
The Peak Power value when the 3 dB amplitude decreases from the saturation level of the reproduction signal amplitude when the ak Power increases.
Double the optimum power level. It is clear from the experimental results that if Bias Power 1 changes, Peak Power
Is changed. That is, Peak
When optimizing Power and Bias Power, first use Peak
If the order of optimizing Power is adopted, Pe will be set according to the initial value of Bias Power arbitrarily given in optimizing Peak Power.
This means that the optimal value of ak Power changes.

FIGS. 4A to 4C show an example of an experiment for determining Bias Power 1. FIG. The horizontal axis is for Bias Power 1. A jitter curve (3T on 11T) when a repeating pattern of a mark of length 3T and a space of length 3T is overwritten on a repeating pattern of a mark of length 11T and a space of length 11T, and a mark of length 3T A jitter curve (11T on 3T) when a repetition pattern of a mark having a length of 11T and a space having a length of 11T is overwritten on a repetition pattern of a space having a length of 11T and a space having a length of 3T is plotted. The vertical axis is the jitter value. The overlapping portion of the two curves is sliced at a jitter value of about 13%, and the average of two bias power 1 values at which the jitter value is 13% is Bi.
Set as the optimal value of as Power 1. Here, when changing Bias Power 1, Bias Power 2 and Bias Power 3 are
It is changed so that the ratio with Bias Power 1 is constant. When such optimization is performed while changing the Peak Power, the same Bi is always used regardless of the Peak Power value.
The value of as Power 1 is obtained. That is, Peak Power and Bi
In optimizing as Power 1, first Bias Power
When 1 is optimized, the correct optimal value of Bias Power 1 is always obtained regardless of the initial value of Peak Power. If Peak Power is subsequently obtained, an appropriate value can be obtained for Peak Power. Above, optimization of Bias Power 1 and Peak P
In the optimization of ower, without using a random pattern,
A repeating pattern of marks and spaces of the same length was used. This is important for determining the power level without depending on the look-up table that has become incompatible. By adopting the above-described optimization order in the above-described recording pattern, an effect is obtained that a correct recording power level can always be determined.

The look-up table is updated in the procedure (2). Since the provisional power level is determined in the procedure (1), the look-up table at an appropriate power level can be determined.
There are various methods for determining the look-up table. However, since the look-up table may be determined by a method convenient for the information recording apparatus, the method for determining the look-up table will not be described here.

Although the recording power level is finally determined in the above (3), the final power level and the look-up table have already been determined in the procedures (1) and (2), but the final recording power level is determined. The recording power level is adjusted to find the optimum recording conditions for the random pattern. Since the look-up table has already been updated in the above procedure (2), the jitter of the random pattern is sufficiently reduced, and the reproduction jitter of the random pattern is an effective means for determining the recording power level. There are various specific power level determination procedures, which may be arbitrarily determined depending on the convenience of the information recording apparatus. An example is shown here. Peak Power Provisional Peak Pow
The random pattern is recorded by changing Bias Power 1 as er, and then this is reproduced to measure the reproduction jitter. Optimal bias power level to minimize playback jitter
Power 1 Or, optimize the bias power level at the middle point between two points where the value of the reproduction jitter crosses 13%
Bias Power 1 After that, Bias Power 1 is optimized Bia
A random pattern is recorded while changing the Peak Power as s Power 1 and then reproduced to measure the reproduction jitter. The optimum peak power is a recording power level that is 1.2 times the recording power level at which the value of the reproduction jitter is 13%. Repeat the setting of Bias Power and Peak Power as necessary. What is important here is the order of power level optimization. From the same necessity as described above, it is important to set Peak Power after optimizing Bias Power 1. Here, it was called "Optimization of Bias Power 1".
As Power 2 and Bias Power 3 are changed in accordance with the change of Bias Power 1 while keeping the ratio with Bias Power 1 constant.

Next, an information recording apparatus according to a second embodiment of the present invention will be described. The configuration of the information recording device according to this embodiment is the same as the configuration of the information recording device according to the first embodiment of the present invention shown in FIG. Therefore, the operation of the information recording apparatus according to the present embodiment will be described below with reference to FIG.

When the necessity of information writing occurs or before the information writing occurs, the power level of the energy beam at the time of information writing may be optimized or the power level value may be updated. Further, the leading edge timing correction look-up table and the rear edge correction look-up table at the time of writing may be optimized or the table values may be updated. In such a case, the system controller 150 sends an appropriate recording pattern to the signal processing circuit 154, and forms a recording mark sequence on the recording medium 100.
Thereafter, the recorded mark sequence is reproduced. The playback signal is
The reproduction signal level is measured by the amplifier 152, and the measured value is sent to the system controller 150. The reproduction signal is binarized by the slicer 170 and then sent to the time interval measurement circuit 171. Time interval measurement circuit 171
Measures the fluctuation (jitter) of the reproduction signal and sends the measurement result to the system controller 150. The system controller 150 changes the recording power level based on the measurement result of the reproduction signal level in the amplifier 152 and the measurement result of the jitter in the time interval measurement circuit 171 according to the procedure described in FIGS. After that, the system controller 150
4 to the recording medium 10 again.
A recording mark string is formed on 0 using a new recording power level. By repeating the measurement of the reproduction signal level and the reproduction jitter and the update of the recording power level based on the measurement result as many times as necessary, the optimum recording power level for the given storage medium 100 can be obtained. Can be determined.

The system controller 150 sends an appropriate recording pattern to the signal processing circuit 154 to form a recording mark sequence on the recording medium 100. Thereafter, the recorded mark sequence is reproduced. The reproduction signal is output to the slicer 170
After that, it is sent to the time interval measuring circuit 171. The time interval measuring circuit 171 measures the fluctuation (jitter) of the reproduction signal, and sends the measurement result to the system controller 150. When the obtained jitter is insufficient, the system controller 150 changes the values of the timing correction lookup tables for the leading edge and the trailing edge according to the procedure described in the description of FIGS. Let it. Thereafter, the system controller 150 sends the appropriate recording pattern to the signal processing circuit 154 again, and forms a recording mark sequence on the recording medium 100 using the new front edge and rear edge timings. As described above, by repeating the measurement of the reproduction jitter and the signal edge shift and the updating of the compensation value of the timing correction look-up table for the front edge and the rear edge based on the measurement results, the optimum value for the given storage medium 100 is obtained. A look-up table for a proper write can be determined when needed.

As described above, according to the present invention, even if the recording characteristics of the information recording apparatus fluctuate due to aging, temperature change, and the like, a highly accurate recording power level and a look for recording compensation are always obtained by a simple procedure. An up-table can be obtained, and the effect that information can always be stably recorded can be obtained.

(Third Embodiment) Next, an information recording method according to a third embodiment of the present invention will be described. First,
The mark sequence to be recorded on the recording medium will be described with reference to FIGS. 5A and 5B.

FIG. 5A shows a second state (hereinafter, referred to as “mark”) and a first state (hereinafter, referred to as “space”) of the recording medium recorded on the recording medium. . Let T be the cycle of a clock (recording timing generation clock) that operates at the reference frequency when recording marks and spaces, and let v be the relative speed between the recording medium and the energy beam. Small recording pattern A (first small recording pattern)
Is a mark having a length avT (a first mark), a space having a length ivT following the first mark (a first space), and a mark having a length mvT following the first space (a second mark). ) And the length jv following the second mark
It consists of a space of T (second space) and a mark (third mark) of length bvT following the second space. The small recording pattern B (second small recording pattern) starts with a space of length C ₁ vT, is followed by a mark of length C ₂ vT, is followed by a space of length C ₃ vT, and has a length of C ₄ vT. mark continues, is intended to end in the space of length C ₅ vT. That is, the small recording pattern B starts in the first state (space) and ends in the first state (space), and the first state (space) and the second state (mark).
Appear finitely alternately. The small recording pattern A and the subsequent small recording pattern B form a basic recording pattern. Here, it is a is a parameter representing the length of the marks and spaces, i, m, j, b and C ₁ -C ₅ are all natural numbers (positive integers).

From the addition value obtained by arithmetically adding all the length parameters of the marks included in the basic recording pattern, the addition value obtained by arithmetically adding all the parameters of the length of the space included in the basic recording pattern is calculated. The reduced value is "Digi
tal Sum Value (DSV) ". By adjusting the length of the mark and the space so that the DSV of the basic recording pattern becomes zero, the quality of the reproduced signal of the mark row is improved.

The recording pattern is a state where the basic recording pattern appears repeatedly, and an example thereof will be described with reference to FIG. 5B. Recording pattern A1 (first recording pattern) is composed of a plurality of basic recording pattern, the change in the basic value of the parameter j recording pattern which has a different value (Fig. 5B, j from j ₁ to j _h What you do). The value of the parameter j may be changed in a random order by setting a lower limit and an upper limit. The recording pattern B1 (second recording pattern) also includes a plurality of basic recording patterns, and the value of the parameter i of each basic recording pattern has various values (in FIG. 5B, i is i ₁
To i _k ). The value of the parameter i may also be changed in a random order by setting a lower limit and an upper limit.

Next, referring to FIGS. 6A and 6B, FIG.
A reproduction signal when the recording pattern A1 and the recording pattern B1 shown in FIG. 5B are recorded and reproduced, and a processing method thereof will be described. For the sake of explanation, the relative movement direction of the energy beam with respect to the recording medium is defined as a direction from the left to the right in the drawing. In a mark, a mark boundary in the direction opposite to the moving direction of the energy beam is referred to as a “front edge”, and a mark boundary in the moving direction of the energy beam is referred to as a “back edge”.

FIG. 6A shows the recording pattern A shown in FIG. 5B.
1 and a reproduction signal corresponding thereto. The position where the reproduction signal crosses the slice level from the upper side of the page to the lower side of the page indicates the leading edge of the reproduction signal. Using a reproduction signal, a time interval from a front edge of a mark having a length avT (first mark) to a front edge of a mark having a length mvT (second mark) is measured by a time interval measuring device, and a measurement time is obtained. and T _1. The measurement time T ₁ is the time interval (a
+ I) No match with T indicates that the leading edge of the mark (the second mark) having the length mvT does not exist at an appropriate position. Thus, the position of the leading edge of the mark (the second mark) having the length mvT can be measured from the reproduced signal.

What is important here is that the length of the space of the length jvT (second space) following the mark of the length mvT (second mark) is variously changed. Irradiation of the energy beam when recording a mark having a length bvT (third mark) is performed using a mark having a length mvT (second mark).
Mark) may cause a change in the front edge position. The amount of change is also a function of the length of the space having the length jvT (the second space). Therefore, the length of the space (second space) having the length jvT is variously changed, and the amount of the change is averaged. Thereby, even if the front edge position of the mark (second mark) of length mvT is fluctuated by the mark (third mark) of length bvT, the average front edge position is measured, and the reliability is improved. The effect of being able to measure the mark edge position with high performance is obtained.

FIG. 6B shows the recording pattern B shown in FIG. 5B.
1 and a reproduction signal corresponding thereto. Using the reproduced signal, the time interval from the trailing edge of the mark mvT (second mark) to the trailing edge of the mark bvT (third mark) is measured by a time interval measuring device, and the measurement time is measured. and T _2. This measurement time T ₂ does not coincide with the time interval (j + b) T, the rear edge of the mark length MVT (second mark) indicates the absence in the proper position. In this way, the position of the trailing edge of the mark (the second mark) having the length mvT can be measured from the reproduced signal.

What is important here is that the length of the space (first space) of length ivT preceding the mark of length mvT (second mark) is variously changed. Irradiation of the energy beam at the time of recording a mark having a length avT (first mark) is performed with a mark having a length mvT (second mark).
May cause the rear edge position to fluctuate. Further, the amount of this variation is a space of length ivT (first
Space) is also a function of length. Therefore, the length of the space (first space) having the length ivT is variously changed, and the amount of the change is averaged. Accordingly, even if the rear edge position of the mark of the length mvT (second mark) is fluctuated by the mark of the length avT (first mark), the average rear edge position is measured, and the reliability is improved. The effect of being able to measure the mark edge position with high performance is obtained.

Next, with reference to FIG. 1, a specific example of the irradiation of an energy beam when forming a mark and a space will be described, and a method for controlling the leading edge and the trailing edge of an arbitrary mark with high accuracy will be described.

As described in the information recording method according to the first embodiment of the present invention, T _SFP and _TELP are converted to NRZI.
By changing the position in accordance with the combination before and after the signal, the mark edge position can always be controlled with high accuracy. However, in order to bring the mark edge position to a predetermined location, it is essential to accurately grasp the current mark edge position. Therefore, highly accurate edge position measurement is performed by the edge position measurement method described with reference to FIGS. 6A and 6B using the recording pattern described with reference to FIGS. 5A and 5B. By forming and correcting a lookup table of T _SFP and _TELP based on the edge position measurement result,
The effect is obtained that highly reliable recording in which all edge positions are aligned with predetermined positions can be performed.

More specifically, the value of one element of the look-up table of the leading edge (for example, the length of the mark (the second mark) is MvT (M is a natural number), and the preceding space (the When it is desired to check the value of the element of the look-up table when the length of 1 space) is IvT (I is a natural number), the value of the parameter i of the small recording pattern A shown in FIG. At the same time, a recording pattern A1 shown in FIG. 5B is created using a basic recording pattern in which the value of the parameter m is M, and this is recorded on a recording medium. Thereafter, the time interval (measurement time T ₁ ) of the reproduced signal from the front edge of the mark of the length avT (first mark) to the front edge of the mark of the length MvT (second mark) is determined by the method described with reference to FIG. 6A. ) Is measured. If the measured time T ₁ is longer than the time interval (a + I) T, since the front edge of a mark length MvT (second mark) is behind nearer than a predetermined position, a lower number of elements in the look-up table I do. That is, T shown in FIG.
Adjust the value of _SFP so that the first pulse starts earlier. On the other hand, when the measurement time T ₁ is shorter than the time interval (a + I) T, since the front edge of a mark length MvT (second mark) is in closer before the predetermined position, the numerical value of the element of the lookup table To increase. That is, the value of T _SFP shown in FIG. 1 is increased, and adjustment is performed so that the leading pulse starts at a later timing. By such an adjustment, the front edge position of the mark (second mark) can be brought to a predetermined position. By performing such an adjustment on all elements of the look-up table relating to the leading edge while changing the value of M and the value of I, what N
The effect that the leading edge can always be stably positioned at a predetermined position can be obtained with respect to the combination of the RZI signals. As a result, the reliability of information storage can be improved.

In another example, the value of one element of the look-up table of the trailing edge (for example, the length of the mark (the second mark) is MvT (M is a natural number) and the space (the second mark) When it is desired to check the value of the element of the lookup table when the length of the space) is JvT (J is a natural number), the value of the parameter j of the small recording pattern A shown in FIG. A recording pattern B1 shown in FIG. 5B is created using a basic recording pattern in which the value of m is M, and this is recorded on a recording medium. Thereafter, the time interval (measurement time T ₂ ) of the reproduced signal from the trailing edge of the mark of the length MvT (second mark) to the trailing edge of the mark of the length bvT (third mark) is determined by the method described with reference to FIG. 6B. ) was measured, when the measured time T ₂ is longer than the time interval (b + J) T, since the rear edge of the mark length MvT (second mark) is in closer before the predetermined position, the look-up table Increase the value of the element. That is, the value of _TELP shown in FIG. 1 is increased so that the final pulse is adjusted to end at a later timing. On the other hand, the measurement time T ₂ is a time interval (b +
J) If it is shorter than T, the value of the element in the lookup table is reduced because the trailing edge of the mark (the second mark) having the length MvT is behind the predetermined position. That is, the value of _TELP shown in FIG. 1 is reduced, and adjustment is performed so that the final pulse ends earlier. By such adjustment, the rear edge position of the mark (the second mark) can be brought to a predetermined position. By performing such adjustment for all elements of the look-up table regarding the trailing edge while changing the value of M and the value of J, what kind of NRZ
The effect that the rear edge can always be stably positioned at a predetermined position with respect to the combination of I signals is obtained. As a result, the reliability of information storage can be improved.

Next, an information recording apparatus according to a third embodiment of the present invention will be described. The configuration of the information recording device according to this embodiment is the same as the configuration of the information recording device according to the first embodiment of the present invention shown in FIG. Therefore, the operation of the information recording apparatus according to the present embodiment will be described below with reference to FIG.

When the necessity of information writing occurs or before the information writing occurs, the look-up table for controlling the leading edge and the trailing edge at the time of information writing may be optimized or updated. . In such a case, the system controller 150
The recording pattern A1 shown in FIG.
Alternatively, the recording pattern B1 is sent, and the recording pattern
The recording mark train described in A and 5B is formed. afterwards,
This recorded mark sequence is reproduced. The reproduced signal is sent to the time interval measuring circuit 171 after being binarized by the slicer 170. The time interval measurement circuit 171 measures the time interval (measurement time T ₁ ) and the time interval (measurement time T ₂ ) described in FIGS. 6A and 6B, and sends the measurement result to the system controller 150. The system controller 150 updates the look-up table according to the procedure described above on the basis of the measured time T ₁ and the measurement time T ₂ received. After that, the system controller 150
4, the recording pattern A1 or the recording pattern B1 is sent again, and a recording mark sequence is formed on the recording medium 100 using the updated look-up table.

By repeating the measurement of the measurement time T ₁ and the measurement time T ₂ and the updating of the look-up table based on the measurement result as many times as necessary, the look-up table for optimal writing to the given storage medium 100 is obtained. Can be created when needed, and the effect that information can always be stably and reliably written to the recording medium 100 can be obtained.

The time interval measuring circuit 171 includes:
A circuit having the function of a time interval analyzer can be considered as an example. As another example, FIG.
In the measurement of the measurement time T ₁ described, constantly monitors the front edge interval of the marks, edge interval before adjacent (a +
a first counter for counting the number of times in the range of (i-0.5) T to (a + i) T, and counting the number of times in which the interval between adjacent front edges is in the range of (a + i) T to (a + i + 0.5) T A second counter for determining whether the time interval T ₁ is longer or shorter than a predetermined time (a + i) T by using a difference between the frequency of the first counter and the frequency of the second counter. Is also good. That is, if the frequency of the first counter is higher than the frequency of the second counter, the measurement time T ₁ is shorter than the predetermined time (a + i) T, while the second
If the frequency of the counter is higher than the frequency of the first counter, the measurement time T ₁ may be determined longer than the predetermined time (a + i) T. Also, the measurement of the measurement time T ₂ described in FIG. 6B, constantly monitors the rear edge interval of the marks,
A third counter for counting the number of times that the adjacent rear edge interval is in the range of (b + j-0.5) T to (b + j) T, and the adjacent front edge interval of (b + j) T to (b + j + 0.5) T And a fourth counter that counts the number of times within the range of, and uses the difference between the frequency of the third counter and the frequency of the fourth counter to determine the measurement time T ₂
May be longer or shorter than a predetermined time (b + j) T. That is, if the frequency of the third counter is higher than the frequency of the fourth counter, the measurement time T ₂ are shorter than the predetermined time (b + j) T, whereas the frequency of the fourth counter is higher than the frequency of the third counter If the measurement time T ₂
May be determined to be longer than the predetermined time (b + j) T. The time measurement by the frequency comparison of the counters can be simplified as compared with the configuration of the time interval analyzer, and as a result, the effect that the reliability is high because of the simplicity can be obtained.

Next, a specific example of a recording mark string will be described using a DVD-RAM as an example. It is desirable that the recording mark string has a DSV of zero, and that an unnecessary mark edge interval does not mix with the mark edge interval to be measured. As an example of a specific recording mark sequence, the recording mark sequence shown in FIGS. 7A and 7B can be considered. The basic recording pattern 2 shown in FIGS.
In one specific example, it is assumed that the parameters i, m, and j are integers of 3 or more and 6 or less. By forming the recording pattern A1 or the recording pattern B1 shown in FIG. 5B using such a basic recording pattern, the DSV is made zero, and an unnecessary mark edge interval is superimposed on the mark edge interval to be measured. Therefore, the effect that the mark edge position measurement can be performed accurately can be obtained.

Next, taking a DVD-RAM as an example, FIG.
An example in which the recording pattern A1 and the recording pattern B1 shown in FIG. In this case, it is assumed that a recording pattern whose basic recording pattern is that shown in FIG. 7A or a recording pattern whose basic recording pattern is that shown in FIG. 7B is used. That is, using the basic recording pattern of FIG.
And a basic recording pattern created by variously changing the parameter j to form a recording pattern C. However, it is assumed that all combinations of the parameter i and the parameter j exist in the basic recording pattern in the recording pattern C under the condition that the parameter i and the parameter j are 3 or more and 6 or less.

FIG. 8 shows a specific example of the recording mark train formed in this manner. This specific example is based on the case where m = 6. The number written in the square frame indicates the parameter of the length of the mark, and the actual length of the mark is the length obtained by multiplying the number written in the square frame by vT. The number written outside the square frame indicates the parameter of the length of the space, and the actual space length is the length obtained by multiplying the number written outside the square frame by vT. The mark / space column is long and is shown folded. Starting from the mark at the upper left of the figure, the mark / space column is shown in the order of space, mark, and space sequentially to the right. After the space on the right side in the figure, the mark on the left side in the figure below one line is connected. The rightmost space on the bottom row in the figure is the end of the recording pattern C. This recording pattern is repeatedly recorded as many times as necessary, and reproduced.

The leading edge interval is measured. The edge position where the front edge interval is close to 13T is the front edge position of a mark having a length of 6T when the length of the preceding space is 3T. The edge position where the front edge interval is in the vicinity of 14T is the front edge position of a mark having a length of 6T when the length of the preceding space is 4T. The edge position where the front edge interval is near 15T is the front edge position of a mark having a length of 6T when the length of the preceding space is 5T. The edge position where the front edge interval is near 16T is the front edge position of a mark having a length of 6T when the length of the preceding space is 6T.

The trailing edge interval is also measured. The edge position where the rear edge interval is near 13T is the rear edge position of a 6T long mark when the length of the subsequent space is 3T. The edge position where the rear edge interval is in the vicinity of 14T is the rear edge position of a mark having a length of 6T when the length of the subsequent space is 4T. The edge position where the rear edge interval is close to 15T is the rear edge position of a mark having a length of 6T when the length of the subsequent space is 5T. The edge position where the rear edge interval is in the vicinity of 16T is the rear edge position of a mark having a length of 6T when the length of the subsequent space is 6T.

As described above, by using the mark and space columns shown in FIGS. 7A and 7B, the front edge and the rear edge of the mark can be measured simultaneously by repeating the same recording pattern C. Further, since DSV is zero, it is possible to measure the edge positions for various combinations of the preceding space and the succeeding space at a given mark length at a time, and it is possible to obtain the effect that the edge position can be measured simply and accurately.

FIG. 9 shows a recording mark string in accordance with m = 5. The arrangement of marks and spaces is the same as in FIG. This recording pattern is repeatedly recorded as many times as necessary, and reproduced.

The leading edge interval is measured. The edge position where the front edge interval is close to 13T is the front edge position of a mark having a length of 5T when the length of the preceding space is 3T. The edge position where the front edge interval is in the vicinity of 14T is the front edge position of a mark having a length of 5T when the length of the preceding space is 4T. The edge position where the front edge interval is near 15T is the front edge position of a mark having a length of 5T when the length of the preceding space is 5T. The edge position where the front edge interval is in the vicinity of 16T is the front edge position of a mark having a length of 5T when the length of the preceding space is 6T.

The trailing edge interval is also measured. An edge position where the rear edge interval is near 13T is a rear edge position of a mark having a length of 5T when the length of the subsequent space is 3T. The edge position where the rear edge interval is in the vicinity of 14T is the rear edge position of a 5T long mark when the length of the subsequent space is 4T. The edge position where the rear edge interval is close to 15T is the rear edge position of a mark having a length of 5T when the length of the subsequent space is 5T. The edge position where the rear edge interval is in the vicinity of 16T is the rear edge position of a mark having a length of 5T when the length of the subsequent space is 6T.

FIG. 10 shows a recording mark string in accordance with m = 4. The arrangement of marks and spaces is the same as in FIG. This recording pattern is repeatedly recorded as many times as necessary, and reproduced.

The leading edge interval is measured. The edge position where the front edge interval is close to 13T is the front edge position of a mark of 4T in length when the length of the preceding space is 3T. The edge position where the front edge interval is in the vicinity of 14T is the front edge position of a mark having a length of 4T when the length of the preceding space is 4T. The edge position where the front edge interval is close to 15T is the front edge position of a mark having a length of 4T when the length of the preceding space is 5T. The edge position where the front edge interval is in the vicinity of 16T is the front edge position of a 4T-long mark when the length of the preceding space is 6T.

The trailing edge interval is also measured. The edge position where the rear edge interval is near 13T is the rear edge position of a 4T long mark when the length of the subsequent space is 3T. The edge position where the rear edge interval is in the vicinity of 14T is the rear edge position of a mark having a length of 4T when the length of the subsequent space is 4T. The edge position where the rear edge interval is close to 15T is the rear edge position of a mark having a length of 4T when the length of the subsequent space is 5T. The edge position where the rear edge interval is in the vicinity of 16T is the rear edge position of a 4T-long mark when the length of the subsequent space is 6T.

FIG. 11 shows a recording mark string in accordance with m = 3. The arrangement of marks and spaces is the same as in FIG. This recording pattern is repeatedly recorded as many times as necessary, and reproduced.

The leading edge interval is measured. An edge position where the front edge interval is near 13T is a front edge position of a mark having a length of 3T when the length of the preceding space is 3T. The edge position where the front edge interval is in the vicinity of 14T is the front edge position of a mark having a length of 3T when the length of the preceding space is 4T. The edge position where the front edge interval is close to 15T is the front edge position of a mark having a length of 3T when the length of the preceding space is 5T. The edge position where the front edge interval is in the vicinity of 16T is the front edge position of a mark having a length of 3T when the length of the preceding space is 6T.

The trailing edge interval is also measured. The edge position where the rear edge interval is near 13T is the rear edge position of a 3T-long mark when the length of the subsequent space is 3T. The edge position where the rear edge interval is in the vicinity of 14T is the rear edge position of a 3T-long mark when the length of the subsequent space is 4T. The edge position where the rear edge interval is close to 15T is the rear edge position of a 3T long mark when the length of the subsequent space is 5T. The edge position where the rear edge interval is in the vicinity of 16T is the rear edge position of a 3T-long mark when the length of the subsequent space is 6T.

In the recording pattern described with reference to FIGS. 8-11, even if the value of m is different, when the length of the preceding space and the length of the following space are 3T, the measurement of the edge interval 13T is performed. Is always performed, and when the length of the preceding space and the length of the following space are 4T, the measurement of the edge interval 14T is always performed. Interval 15T
Is always measured, and when the length of the preceding space and the length of the succeeding space are 6T, the measurement of the edge interval 16T is always performed. That is, since it is sufficient to always measure the same edge interval without depending on m, the measurement is simplified, and the effect that simple and accurate edge position detection can be performed can be obtained.

Next, a processing method for evaluating the edge position with a simple circuit system using the recording patterns shown in FIGS. 8-11 will be described. A first counter that monitors the interval between adjacent leading edges and counts the number of times that the leading edge interval enters a time interval of length 11.5T to length 12.5T; A second counter for counting the number of times entering the time interval of 13.5T, a third counter for counting the number of times that the leading edge interval enters the time interval of length 13.5T to 14.5T in length, and a leading edge interval Has a length of 14.5
A fourth counter that counts the number of times from T into a time interval of 15.5T in length, and a fifth counter that counts the number of times that the leading edge interval enters a time interval of 15.5T in length from 15.5T in length. Used. Using the difference between the count of the first counter and the count of the second counter, the length of the preceding space is 3
The front edge position in the case of T is estimated. Using the difference between the count of the second counter and the count of the third counter, the leading edge position when the length of the preceding space is 4T is estimated. Using the difference between the counts of the third counter and the fourth counter, the leading edge position when the length of the preceding space is 5T is estimated. Using the difference between the count of the fourth counter and the count of the fifth counter, the length of the preceding space is 6
The front edge position in the case of T is estimated.

Thereafter, the interval between the adjacent rear edges is monitored, and the edge interval is measured using the first to fifth counters described above. Using the difference between the count of the first counter and the count of the second counter, the length of the subsequent space is 3T.
Then, the rear edge position is estimated. Also, the position of the trailing edge when the length of the subsequent space is 4T is estimated using the difference between the count of the second counter and the count of the third counter. Using the difference between the count of the third counter and the count of the fourth counter, the rear edge position is estimated when the length of the subsequent space is 5T. Using the difference between the count of the fourth counter and the count of the fifth counter, the trailing edge position when the length of the subsequent space is 6T is estimated.

By employing the above configuration,
By preparing five simple counters, all NR
The effect is obtained that the look-up table for controlling the mark edge position for the combination before and after the ZI signal can be determined accurately.

In the description of FIG. 8-11, the basic recording pattern shown in FIG. 7B is used, but the basic recording pattern shown in FIG. 7A is used to perform recording in the same manner as that described in FIG. 8-11. Similar effects can be obtained by forming a mark row. In this case, the effect is obtained that the total number of marks and spaces is reduced and the generation of the recording pattern is simplified.

[0133]

According to the present invention, even in a high-density recording situation in which the shortest recording mark length is equal to or less than the recording spot radius, it is possible to always stably position the recording mark edge at a predetermined position, The effect is obtained that information can always be stably and reliably recorded on the recording medium.

[Brief description of the drawings]

FIG. 1 is a diagram showing a specific example of a time modulation method (write strategy) of an energy beam irradiation amount according to the present invention.

FIG. 2 is a block diagram of an information recording device according to the present invention.

FIG. 3 is a diagram showing an example of an experimental result of a reproduction signal amplitude with respect to a value of Peak Power.

FIGS. 4A to 4C are diagrams illustrating an example of an experimental result of a reproduction signal jitter with respect to a value of a bias power.

FIGS. 5A and 5B are explanatory diagrams of mark strings to be recorded on a recording medium.

FIGS. 6A and 6B are explanatory diagrams of a reproduced signal. FIG.

FIGS. 7A and 7B are diagrams showing specific examples of basic recording patterns.

FIG. 8 shows a specific example of a recording pattern (the length of the mark is 6).
vT).

FIG. 9 is a specific example of a recording pattern (the length of the mark is 5).
vT).

FIG. 10 is a diagram showing a specific example of a recording pattern (the length of the mark is 4 vT).

FIG. 11 is a diagram showing a specific example of a recording pattern (the length of the mark is 3 vT).

Continuing on the front page (72) Inventor Mitsuhide Miyamoto 1-280 Higashi Koikekubo, Kokubunji-shi, Tokyo Inside the Hitachi, Ltd.Central Research Laboratories (72) Inventor Hiroyuki Minemura 1-280 Higashi Koigakubo, Kokubunji-shi, Tokyo Inside the Hitachi, Ltd.Central Research Laboratories (72) Inventor Tsuyoshi Toda 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Japan Digital Media Development Division, Hitachi, Ltd.

Claims (35)

[Claims] 1. Recording capable of entering a first state at a first power level of an energy beam and a second state at a second power level higher than said first power level of said energy beam. Using a medium, the energy beam and the recording medium are relatively moved to irradiate the energy beam onto the recording medium, and the first state and the second state are set at a predetermined length and interval. An information recording method for recording information on the recording medium by forming the information on the recording medium, wherein a third power level equal to or lower than the first power level is provided, and the second power level is provided on the recording medium. When forming the region of the state, when forming the region of the second state to a specific length, the period of the third power level is mixed with the period of the second power level, Irradiating the recording medium with the energy beam by multi-pulsing the beam, providing a fourth power level equal to or lower than the first power level, following the last pulse of the multi-pulsed energy beam Irradiating the recording medium with the energy beam at the fourth power level for a predetermined period, multiplying the second power level by x to obtain a new second power level, and setting the first power level to multiply by y to obtain a new first power level, multiply the third power level by y to obtain a new third power level, and multiply the fourth power level by y to obtain new fourth power level The information is recorded on the recording medium while the values of the magnification x and the magnification y are variously changed, and the recorded information is reproduced to obtain a reproduction signal. Tsu value of data to adjust the value of the ratio x and the ratio y to be equal to or less than the predetermined value, the information recording method. 2. The information recording method according to claim 1, wherein the procedure for determining the values of the magnification x and the magnification y includes a first procedure, a second procedure, and a third procedure. 1
The procedure is to set the value of the magnification y to 1 and change the magnification x within a range not less than the lower limit value xs of the magnification x and not more than the upper limit value xm of the magnification x to minimize the reproduction jitter. The value x1 of x is obtained, the value x2 of the magnification x at which the value of the reproduction jitter becomes the value a is obtained, and the value x of c times the value x2 is obtained.
3 and the smaller value x4 of the value x1 and the value x3 is determined. The second procedure is to set the value of the magnification x to the value x4 and to set the value of the magnification x to the lower limit value ys or more. The magnification y is changed within a range not more than the upper limit value ym of the magnification y to determine a value y1 of the magnification y at which the reproduction jitter is minimized. The value is set to a value y1, and the magnification x is changed within a range of not less than the lower limit xs of the magnification x and not more than the upper limit xm of the magnification x, and the value x of the magnification x at which the reproduction jitter is minimized
5 and the magnification x at which the value of the reproduction jitter becomes a value a.
The value x6 of c, the value x7 of c times the value x6 is determined, and the smaller value x8 of the value x5 and the value x7 is determined. The information recording method includes the first procedure,
The magnification x in the order of the second procedure and the third procedure
And adjusting the values of the magnification x and the magnification y while changing the magnification y, and changing the adjusted values of the magnification x and the magnification y to an appropriate value x8 of the magnification x and an appropriate value y1 of the magnification y. The information recording method that is finally decided on. 3. The information recording method according to claim 1, wherein recording control information is previously written as non-erasable information on a recording medium to be recorded, and said recording control information is reproduced to produce said first power. An information recording method for determining an initial value of a level, an initial value of the second power level, an initial value of the third power level, and an initial value of the fourth power level. 4. A recording capable of entering the first state at a first power level of the energy beam and the second state at a second power level higher than the first power level of the energy beam. Using a medium, the energy beam and the recording medium are relatively moved to irradiate the energy beam onto the recording medium, and the first state and the second state are set at a predetermined length and interval. An information recording method for recording information on the recording medium by forming the information on the recording medium, wherein a third power level equal to or lower than the first power level is provided, and the second power level is provided on the recording medium. When forming the region of the state, when forming the region of the second state to a specific length, the period of the third power level is mixed with the period of the second power level, Irradiating the recording medium with the energy beam by multi-pulsing the beam, providing a fourth power level equal to or lower than the first power level, following the last pulse of the multi-pulsed energy beam Irradiating the recording medium with the energy beam at the fourth power level for a predetermined period, multiplying the first power level by z to obtain a new first power level, and setting the second power level to multiply by z to obtain a new second power level, multiply the third power level by z to obtain a new third power level, and multiply the fourth power level by z to obtain a new fourth power level And recording the information on the recording medium while changing the value of the magnification z in various ways, and reproducing the recorded information to obtain a reproduction signal, and the value of the reproduction jitter of the reproduction signal. Wherein adjusting the value of the magnification z, the information recording method to be equal to or less than the predetermined value. 5. The information recording method according to claim 4, wherein recording control information is written in advance as non-erasable information on a recording medium to be recorded, and the recording control information is reproduced to produce the first power. An information recording method for determining an initial value of a level, an initial value of the second power level, an initial value of the third power level, and an initial value of the fourth power level. 6. An information recording apparatus, comprising: an energy beam generator that generates an energy beam; and a power level of the energy beam, the power level being set to a first power level and the first power level.
A power adjustment mechanism for setting a second power level higher than the power level of the first power level, and a recording medium capable of setting the first power level to the first state and the second power level to the second state. Holding mechanism, a moving mechanism for relatively moving the energy beam and the recording medium, a positioning mechanism for irradiating the energy beam to a predetermined location on the recording medium, and information for recording the energy A signal processing circuit for changing to a power level of a beam, wherein the power adjustment mechanism forms the area in the second state in a specific length when forming the area in the second state on the recording medium. In the case where the energy beam is formed at a third power level, the period of the third power level equal to or lower than the first power level is mixed with the period of the second power level so that the energy beam is focused. And irradiating the recording medium with the energy beam at a fourth power level equal to or lower than the first power level for a predetermined period following the last pulse of the multi-pulsed energy beam. And a function of setting a value obtained by multiplying the second power level by x as a new second power level, and setting a value obtained by multiplying the first power level by y as a new first power level Function to set a value obtained by multiplying the third power level by y as a new third power level, and set a value obtained by multiplying the fourth power level by y as a new fourth power level The information recording apparatus irradiates the recording medium with the energy beam while changing the values of the magnification x and the magnification y in various ways. A time interval measuring circuit for forming a state and the second state on the recording medium and measuring a fluctuation of a reproduced signal obtained by reproducing the first state and the second state, and the time interval measuring circuit An information recording apparatus, further comprising: a controller that adjusts the values of the magnification x and the magnification y such that the fluctuation value of the reproduction signal obtained in step 1 is equal to or less than a predetermined value. 7. The information recording apparatus according to claim 6, wherein the procedure for determining the values of the magnification x and the magnification y includes a first procedure, a second procedure, and a third procedure. First
The procedure of (1) sets the value of the magnification y to 1 and changes the magnification x within a range not less than the lower limit value xs of the magnification x and not more than the upper limit value xm of the magnification x to minimize the fluctuation of the reproduction signal. The value x1 of the magnification x is obtained, and the value x2 of the magnification x at which the fluctuation value of the reproduction signal becomes the value a is obtained.
A value x3 of c times 2 is obtained, and a smaller value x4 of the value x1 and the value x3 is obtained. In the second procedure, the value of the magnification x is x4 and the value of the magnification y is And changing the magnification y within a range not less than a lower limit value ys and not more than an upper limit value ym of the magnification y to obtain a value y1 of the magnification y at which the fluctuation of the reproduction signal is minimized.
Is the value of the magnification y, and changes the magnification x within a range not less than the lower limit value xs of the magnification x and not more than the upper limit value xm of the magnification x to minimize the fluctuation of the reproduction signal. The value x5 of the magnification x is obtained, the value x6 of the magnification x at which the fluctuation value of the reproduction signal becomes the value a is obtained, the value x7 of c times the value x6 is obtained, and the value x5 and the value x7 are obtained.
The smaller value x8 is obtained, and the information recording apparatus changes the magnification x and the magnification y in the order of the first procedure, the second procedure, and the third procedure. Adjusting the values of the magnification x and the magnification y, and finally determining the adjusted values of the magnification x and the y as an appropriate value x8 of the magnification x and an appropriate value y1 of the magnification y. Recording device. 8. An information recording apparatus according to claim 6, wherein the recording control information is pre-written as non-erasable information on a recording medium to be recorded, wherein the initial value of said first power level and said second An information recording device, wherein an initial value of a power level, an initial value of the third power level, and an initial value of the fourth power level are determined by reproducing the recording control information. 9. An information recording apparatus, comprising: an energy beam generator for generating an energy beam; a power level of the energy beam being set to a first power level and a second power level higher than the first power level. A power adjusting mechanism for setting, a holding mechanism for holding a recording medium capable of being in a first state at the first power level, and a second state at the second power level; A moving mechanism that relatively moves the recording medium, a positioning mechanism that irradiates the energy beam to a predetermined location on the recording medium, and a signal processing circuit that changes information to be recorded to a power level of the energy beam. When the power adjustment mechanism forms the area in the second state on the recording medium, the area in the second state is specified. In the case where the energy beam is formed at the same time, a function of multiplying the energy beam by mixing a third power level period equal to or lower than the first power level with the period of the second power level; Following the last pulse of the pulsed energy beam, irradiating the recording medium with the energy beam at a fourth power level equal to or lower than the first power level for a predetermined period of time; Power level z
A function for setting the multiplied value as a new first power level, a function for setting a value obtained by multiplying the second power level by z as a new second power level, and a function for setting the third power level to z The information recording apparatus has a function of setting the multiplied value as a new third power level and a function of setting a value obtained by multiplying the fourth power level by z as a new fourth power level. Irradiating the recording medium with the energy beam while changing the value of the magnification z in various ways to form the first state and the second state on the recording medium, and the first state and the second state. A time interval measuring circuit for reproducing the state of the reproduced signal and measuring the fluctuation of the reproduced signal; and setting the value of the magnification z so that the fluctuation value of the reproduced signal obtained by the time interval measuring circuit becomes a predetermined value or less. Controller to adjust Further comprising an information recording apparatus. 10. An information recording apparatus according to claim 9, wherein
Recording control information is previously written as non-erasable information on a recording medium to be recorded, and the initial value of the first power level, the initial value of the second power level, and the initial value of the third power level And an initial value of the fourth power level is determined by reproducing the recording control information. 11. Recording capable of entering an energy beam in a first state at a first power level and an energy beam in a second state at a second power level higher than the first power level. Using a medium, the energy beam and the recording medium are relatively moved to irradiate the recording medium with the energy beam, and the power level of the energy beam is changed according to the information to be recorded. A pulse train of the energy beam is formed by changing between a plurality of power levels including a power level and the second power level, and the first state and the second state are formed at a predetermined length and interval. An information recording method for recording information on the recording medium by forming the information on the recording medium, wherein the second power level is fixed to an appropriate initial value. Power level values to optimize the said first power level is fixed to the optimized value for optimizing the second power level, information recording method. 12. The information recording method according to claim 11, wherein a power level equal to or lower than the first power level among the power levels other than the first power level and the second power level at the time of recording the information is: In all cases, the ratio of the first power level to the first power level is kept constant.
An information recording method that can be changed according to a change in the power level of the information. 13. Recording capable of entering an energy beam in a first state at a first power level and a second state at a second power level higher than said first power level of said energy beam. Using a medium, while irradiating the recording medium with the energy beam by relatively moving the energy beam and the recording medium, the first power level and the first power level according to the information to record the energy level. A pulse train of an energy beam is formed by changing between a plurality of power levels including a second power level, and the first state and the second state are formed on the recording medium at predetermined lengths and intervals. An information recording method for recording information on the recording medium by forming the information, wherein the energy corresponding to a head of the second state to be formed on the recording medium is provided. A first timing adjustment method for adjusting the timing of the pulse of the energy beam, and a second timing adjustment for adjusting the timing of the pulse of the energy beam corresponding to an end portion of the second state to be formed on the recording medium A first method for adjusting a timing according to the first timing adjustment method and the second timing adjustment method after optimizing a power level by the information recording method according to claim 11. 12. An adjustment procedure and at least a second adjustment procedure of optimizing a power level by the information recording method according to claim 11, after adjusting the timing according to the first timing adjustment method and the second timing adjustment method. An information recording method having one. 14. The information recording method according to claim 13, wherein
12. The power level optimization according to claim 11, wherein the first adjustment procedure uses a repetitive recording pattern of the first state and the second state having the same length. 12. The information recording method according to claim 11, wherein in the optimization of the power level, a recording pattern of a repetition of the first state and the second state, each having a random length, is used. 15. An information recording apparatus, comprising: an energy beam generator for generating an energy beam; and a power level of the energy beam set to a first power level and a second power level higher than the first power level. A power adjusting mechanism that can be set, a holding mechanism that holds a recording medium that can be brought into a first state at the first power level, and a second state at the second power level, and the energy beam. A moving mechanism for relatively moving the recording medium and the recording medium; a positioning mechanism for irradiating the energy beam to a predetermined location on the recording medium; and a signal processing circuit for changing information to be recorded to a power level of the energy beam. Setting the power level at the time of recording, fixing the second power level to an appropriate initial value, and setting the first power level After optimization, and means for optimizing the second power level by fixing the first power level to said optimized value, the information recording apparatus. 16. An information recording apparatus according to claim 15, wherein said first power level and said second power level at the time of recording information are other than said first power level and said second power level.
Are changed in accordance with the change in the second power level while maintaining a constant ratio with the second power level, and the first power level during information recording is changed. Power level and the second
All the power levels equal to or lower than the first power level of the power levels other than the power level of the first power level are maintained at a constant ratio with the first power level.
An information recording device that can be changed according to a change in the power level of the information. 17. An information recording apparatus, comprising: an energy beam generator for generating an energy beam; and a power level of the energy beam set to a first power level and a second power level higher than the first power level. A power adjusting mechanism that can be set, a holding mechanism that holds a recording medium that can be brought into a first state at the first power level, and a second state at the second power level, and the energy beam. A moving mechanism for relatively moving the recording medium and the recording medium; a positioning mechanism for irradiating the energy beam to a predetermined location on the recording medium; and a signal processing circuit for changing information to be recorded to a power level of the energy beam. And the timing of the pulse of the energy beam corresponding to the head of the second state to be formed on the recording medium. At least one of a first timing adjustment unit for adjusting the timing of the energy beam pulse corresponding to an end portion of the second state to be formed on the recording medium; A third timing adjusting unit that adjusts a timing in the first timing adjusting unit and the second timing adjusting unit after optimizing a power level by the optimizing unit according to claim 15; and the first timing adjusting unit. 16. An information recording apparatus comprising: at least one of a timing adjusting unit and at least one of a fourth timing adjusting unit that optimizes a power level by the optimizing unit after the timing adjustment in the second timing adjusting unit. apparatus. 18. An information recording apparatus according to claim 17, wherein the optimization of the power level by the optimizing means in the third timing adjusting means is performed in the first state and the second state having the same length. The fourth timing adjusting means uses a state repetition pattern.
An information recording apparatus using a random pattern in optimizing a power level by the optimizing means described above. 19. Recording capable of entering the first state at a first power level of the energy beam and the second state at a second power level higher than the first power level of the energy beam. Using a medium, the energy beam and the recording medium are relatively moved to irradiate the energy beam onto the recording medium, and the first state and the second state are set at a predetermined length and interval. An information recording method for recording information on the recording medium by forming the information beam on the recording medium, wherein a period of a recording timing generation clock during recording is T, and a relative speed between the energy beam and the recording medium is v , The second state (first mark) having a length avT, the first state (first space) having a length ivT following the first mark, the first space The second state (the second mark) having a length mvT following the second mark, the first state (the second space) having a length jvT following the second mark, and the length following the second space. The second of bvT
The first state and the second state alternately appear a finite number of times, starting from the first state and ending with the first state. A state is a second small recording pattern, a state in which the second small recording pattern appears following the first small recording pattern is a basic recording pattern, a state in which the basic recording pattern appears repeatedly is a recording pattern, The above-mentioned recording pattern comprising a basic recording pattern in which the parameter j is variously changed while fixing the parameter a, the parameter i and the parameter m is defined as a first recording pattern.
The parameters a, i, m, and j are natural numbers, and the parameter b, the parameter j, and the parameter m are fixed, and the parameter i is variously changed while the basic recording pattern is changed to the second recording. A pattern, wherein the parameter b is a natural number, and at least one of a first edge position measuring method and a second edge position measuring method is used, and the first edge position measuring method is the first edge position measuring method. It corresponds to a boundary position between the second mark and the first space in the read signal from a time corresponding to a mark edge position opposite to the first space of the first mark in the read signal of the recording pattern. The second mark and the first mark are compared by comparing the time interval up to the time of the second mark with the time interval of (a + i) T.
A position corresponding to a boundary position between the second mark and the second space in the read signal of the second recording pattern by estimating the position of the boundary with the space. Is a time interval from (b + j) T to a time corresponding to a mark edge position on the opposite side of the third space of the third mark in the read signal from the second space.
An information recording method of estimating a position of a boundary between the second mark and the second space by comparing the time interval with the second time interval. 20. An information recording method according to claim 19, wherein said parameter a = 10 and said parameter b = 1.
0, the parameters i, j, and m are natural numbers of 3 or more and 6 or less, respectively, and the second small recording pattern is composed of the first state having a length (15-i) vT and a subsequent length of 9 vT And the subsequent length (14 + m−
j) An information recording method comprising the first state of vT. 21. An information recording method according to claim 19, wherein said parameter a = 10 and said parameter b = 1.
0, the parameters i, j, and m are natural numbers of 3 or more and 6 or less, respectively, and the second small recording pattern is composed of the first state having a length (15-i) vT and a subsequent length of 9 vT Said second state and a subsequent length (15-j)
An information recording method, comprising: the first state of vT, the second state of 9 vT in length, and the first state of (8 + m) vT in length. 22. Recording capable of being in a first state at a first power level of an energy beam and in a second state at a second power level higher than said first power level of said energy beam. Using a medium, the energy beam and the recording medium are relatively moved to irradiate the energy beam onto the recording medium, and the first state and the second state are set at a predetermined length and interval. An information recording method for recording information on the recording medium by forming the information beam on the recording medium, wherein a period of a recording timing generation clock during recording is T, and a relative speed between the energy beam and the recording medium is v , The second state (first mark) of length avT, the first state (first space) of length ivT following the first mark,
The second state (second mark) having a length mvT following the first space, the first state (second space) having a length jvT following the second mark, and the second state. A continuation of the second state (third mark) having a length bvT following the space is defined as a first small recording pattern,
A first state starting from the first state and ending at a first state;
A state in which the second state and the second state alternately appear finite times is defined as a second small recording pattern, and a state in which the second small recording pattern appears following the first small recording pattern is defined as a basic recording pattern. A state in which the basic recording pattern repeatedly appears is a recording pattern, and a recording pattern including a basic recording pattern in which parameter a, parameter i, and parameter m are fixed and parameter j is variously changed is defined as a first recording pattern. Where the parameters a, i, m, and j are natural numbers, and the parameter b, the parameter j, and the parameter i are variously changed while the parameter i is varied while the parameter m is fixed. Where the parameter b is a natural number, which is different from the first edge position measuring method. The method has at least one of a second edge position measuring method, and has at least one of a first timing adjusting method and a second timing adjusting method, and the first edge position measuring method is the first edge adjusting method. It corresponds to a boundary position between the second mark and the first space in the read signal from a time corresponding to a mark edge position opposite to the first space of the first mark in the read signal of the recording pattern. By comparing the time interval up to the time of the second mark with the time interval of (a + i) T, the position of the boundary between the second mark and the first space is estimated, and the second edge position measuring method includes: From the time corresponding to the boundary position between the second mark and the second space in the read signal of the second recording pattern, the third mark of the read signal is read from the time corresponding to the boundary position. By comparing the time interval up to the time corresponding to the mark edge position opposite to the second space with the time interval of (b + j) T, the position of the boundary between the second mark and the second space is determined. And the first timing adjusting method adjusts the energy beam according to the combination of the length of the first state and the length of the second state to be formed on the recording medium. Changing the timing of reaching the power level, wherein the second timing adjustment method adjusts the energy according to a combination of the length of the second state to be formed on the recording medium and the length of the first state. An information recording method, wherein a timing at which a beam is shifted from the second power level to another energy level is changed. 23. An information recording method according to claim 22, wherein said parameter a = 10 and said parameter b = 1.
0, the parameters i, j, and m are natural numbers of 3 or more and 6 or less, respectively, and the second small recording pattern is composed of the first state having a length (15-i) vT and a subsequent length of 9 vT And the subsequent length (14 + m−
j) An information recording method comprising the first state of vT. 24. An information recording method according to claim 22, wherein said parameter a = 10 and said parameter b = 1.
0, the parameters i, j, and m are natural numbers of 3 or more and 6 or less, respectively, and the second small recording pattern is composed of the first state having a length (15-i) vT and a subsequent length of 9 vT Said second state and a subsequent length (15-j)
An information recording method, comprising: the first state of vT, the second state of 9 vT in length, and the first state of (8 + m) vT in length. 25. Recording capable of being in a first state at a first power level of an energy beam and in a second state at a second power level higher than said first power level of said energy beam. Using a medium, the energy beam and the recording medium are relatively moved to irradiate the energy beam onto the recording medium, and the first state and the second state are set at a predetermined length and interval. An information recording method for recording information on the recording medium by forming the information beam on the recording medium, wherein a period of a recording timing generation clock at the time of recording is T, and a relative speed between the energy beam and the recording medium is v, the second state (first mark) having a length avT, the first state (first space) having a length ivT following the first mark, and the first space The second state (the second mark) having a length mvT following the second mark, the first state (the second space) having a length jvT following the second mark, and the length following the second space. The second of bvT
The first state and the second state alternately appear a finite number of times, starting from the first state and ending with the first state. A state is a second small recording pattern, a state in which the second small recording pattern appears following the first small recording pattern is a basic recording pattern, a state in which the basic recording pattern appears repeatedly is a recording pattern, The above-mentioned recording pattern comprising a basic recording pattern in which the parameter j is variously changed while fixing the parameter a, the parameter i and the parameter m is defined as a first recording pattern.
The parameters a, i, m, and j are natural numbers, and the parameter b, the parameter j, and the parameter m are fixed, and the parameter i is variously changed while the basic recording pattern is changed to the second recording. The parameter b is a natural number, and at least one of the first edge position measuring method and the second edge position measuring method is used. Having at least one of
The method includes at least one of a first timing correction method and a second timing correction method, wherein the first edge position measurement method is configured to perform the first edge position measurement method based on the first mark of the first mark in the read signal of the first recording pattern. The time interval from the time corresponding to the mark edge position on the opposite side to the space corresponding to the space corresponding to the boundary position between the second mark and the first space in the read signal is defined as the time interval of (a + i) T. By performing the comparison, the position of the boundary between the second mark and the first space is estimated, and the second edge position measuring method uses the second mark in the read signal of the second recording pattern. From the time corresponding to the boundary position between the third mark and the second space, the read signal corresponds to the mark edge position of the third mark opposite to the second space. By comparing the time interval up to the time interval with the time interval of (b + j) T, the position of the boundary between the second mark and the second space is estimated, and the first timing adjustment method uses the recording method. Changing a timing at which the energy beam reaches the second power level according to a combination of a length of the first state and a length of the second state to be formed on a medium; The adjusting method changes the energy beam from the second power level to another energy level according to a combination of the length of the second state to be formed on the recording medium and the length of the first state. Changing the timing, wherein the first timing correction method adjusts the timing in the first timing adjustment method based on a result of the first edge position measurement method. And integer, the second timing correction method is to adjust the timing of the second timing adjustment method based on the results of the second edge position measuring method, an information recording method. 26. An information recording method according to claim 25, wherein said parameter a = 10 and said parameter b = 1.
0, the parameters i, j, and m are natural numbers of 3 or more and 6 or less, respectively, and the second small recording pattern is composed of the first state having a length (15-i) vT and a subsequent length of 9 vT And the subsequent length (14 + m−
j) An information recording method comprising the first state of vT. 27. An information recording method according to claim 25, wherein said parameter a = 10 and said parameter b = 1.
0, the parameters i, j, and m are natural numbers of 3 or more and 6 or less, respectively, and the second small recording pattern is composed of the first state having a length (15-i) vT and a subsequent length of 9 vT Said second state and a subsequent length (15-j)
An information recording method, comprising: the first state of vT, the second state of 9 vT in length, and the first state of (8 + m) vT in length. 28. Recording capable of being in a first state at a first power level of an energy beam and in a second state at a second power level higher than said first power level of said energy beam. Using a medium, the energy beam and the recording medium are relatively moved to irradiate the energy beam onto the recording medium, and the first state and the second state are set at a predetermined length and interval. An information recording method for recording information on the recording medium by forming the information beam on the recording medium, wherein a period of a recording timing generation clock during recording is T, and a relative speed between the energy beam and the recording medium is v , The second state (first mark) of length avT, the first state (first space) of length ivT following the first mark,
The second state (second mark) having a length mvT following the first space, the first state (second space) having a length jvT following the second mark, and the second state. A continuation of the second state (third mark) having a length bvT following the space is defined as a first small recording pattern,
Starting from the first state and ending with the first state;
A state in which the first state and the second state alternately appear a finite number of times is referred to as a second small recording pattern, and a state in which the second small recording pattern appears following the first small recording pattern is a basic state. A state in which the basic recording pattern repeatedly appears is referred to as a recording pattern, and the recording pattern composed of the basic recording pattern in which the parameter j is variously changed while the parameter a, the parameter i, and the parameter m are fixed is defined as a first pattern. Recording pattern,
Here, the parameters a, i, m, and j are natural numbers, and the recording pattern composed of the basic recording pattern in which the parameter i is variously changed while the parameter b, the parameter j, and the parameter m are fixed. Here, the parameter b is a natural number, and at least one of the first edge position measuring method and the second edge position measuring method is used, and the first timing adjusting method and the second The method includes at least one of a timing adjustment method and at least one of a first timing correction method and a second timing correction method, wherein the first edge position measurement method reads the first recording pattern. From the time corresponding to the mark edge position of the signal opposite to the first space of the first mark, The time interval between the time corresponding to the boundary position between the second mark the first space (a +
i) estimating the position of the boundary between the second mark and the first space by comparing with the time interval of T;
The second edge position measuring method may be configured so that the second mark and the second mark in the read signal of the second recording pattern
The time interval from the time corresponding to the boundary position with the space to the time corresponding to the mark edge position of the third mark in the read signal opposite to the second space is defined as the time interval of (b + j) T. By comparing
The position of the boundary between the second mark and the second space is estimated, and the first timing adjustment method determines the length of the first state to be formed on the recording medium and the second state The timing at which the energy beam reaches the second power level is changed according to a combination of the length of the second state and the length of the second state to be formed on the recording medium. And changing the timing at which the energy beam is shifted from the second power level to another energy level according to a combination of the first state and the length of the first state. From the time corresponding to the mark edge position of the pattern read signal opposite to the first space of the first mark, the second mark in the read signal is read. If it is determined from the first edge position measurement method that the time interval until the time corresponding to the boundary position between the mark and the first space is longer than the time interval of (a + i) T, Only when the second state having the length mT is formed following the first state having the length iT using the timing adjustment method 1 described above, when the second state having the length mT is formed. The timing for reaching the second power level is advanced and the first power level is reached.
From the time corresponding to the mark edge position on the opposite side of the first space of the first mark in the read signal of the recording pattern, to the boundary position between the second mark and the first space in the read signal If the conclusion from the first edge position measurement method is that the time interval until the time to perform is shorter than the time interval of (a + i) T, the first timing adjustment method is used to determine the length iT. Only when forming the second state having the length mT subsequent to the first state, delay the timing of reaching the second power level when forming the second state having the length mT. The second timing correction method may be configured to perform the read signal from a time corresponding to a boundary position between the second mark and the second space in the read signal of the second recording pattern. Concluded from the second edge position measurement method that the time interval until the time corresponding to the mark edge position of the third mark opposite to the second space in the above is longer than the time interval of (b + j) T. If obtained, the second state having a length of mT is followed by the first state having a length of jT using the second timing adjustment method.
Only when the second state is formed, the timing of transition from the second power level to another energy level when forming the second state having the length mT is delayed, and the reading of the second recording pattern is performed. From a time corresponding to a boundary position between the second mark and the second space in the signal to a time corresponding to a mark edge position of the third mark opposite to the second space in the read signal. If the conclusion that the time interval is shorter than the time interval of (b + j) T is obtained from the second edge position measurement method, the second state of length mT is used by using the second timing adjustment method. Then, only when the first state having the length jT is formed, it is deduced from the second power level when forming the second state having the length mT to another energy level. Advancing the timing of the information recording method. 29. An information recording method according to claim 28, wherein said parameter a = 10 and said parameter b = 1.
0, the parameters i, j, and m are natural numbers of 3 or more and 6 or less, respectively, and the second small recording pattern is composed of the first state having a length (15-i) vT and a subsequent length of 9 vT And the subsequent length (14 + m−
j) An information recording method comprising the first state of vT. 30. The information recording method according to claim 28, wherein said parameter a = 10 and said parameter b = 1.
0, the parameters i, j, and m are natural numbers of 3 or more and 6 or less, respectively, and the second small recording pattern is composed of the first state having a length (15-i) vT and a subsequent length of 9 vT Said second state and a subsequent length (15-j)
An information recording method, comprising: the first state of vT, the second state of 9 vT in length, and the first state of (8 + m) vT in length. 31. Information that can be brought into a first state at a first power level of an energy beam and into a second state at a second power level higher than the first power level of the energy beam. 26. A recording medium, wherein:
At least one of the information on the timing of reaching the second power level and the information on the timing of transition from the second power level to another energy level determined using the information recording method described above is regarded as non-rewritable information. An information recording medium that has been recorded. 32. Information capable of entering an energy beam in a first state at a first power level and an energy beam in a second state at a second power level higher than the first power level. 29. A recording medium, wherein:
At least one of the information on the timing of reaching the second power level and the information on the timing of transition from the second power level to another energy level determined using the information recording method described above is regarded as non-rewritable information. An information recording medium that has been recorded. 33. An information recording apparatus, comprising: an energy beam generator for generating an energy beam; and a power level of the energy beam set to a first power level and a second power level higher than the first power level. A power adjusting mechanism that can be set, a holding mechanism that holds a recording medium that can be brought into a first state at the first power level, and a second state at the second power level, and the energy beam. A moving mechanism for relatively moving the recording medium and the recording medium; a positioning mechanism for irradiating the energy beam to a predetermined location on the recording medium; and a signal processing circuit for changing information to be recorded to a power level of the energy beam. Reading the non-rewritable information recorded on the information recording medium using the information recording medium according to claim 31. Means for decoding at least one of the information of the timing of reaching the second power level and the information of the timing of transitioning from the second power level to another energy level, and storing the second state in the recording medium. Means for modulating an energy pulse in accordance with the decoded timing information when forming the information recording apparatus. 34. An information recording apparatus, comprising: an energy beam generator for generating an energy beam; and a power level of the energy beam set to a first power level and a second power level higher than the first power level. A power adjusting mechanism that can be set, a holding mechanism that holds a recording medium that can be brought into a first state at the first power level, and a second state at the second power level, and the energy beam. A moving mechanism for relatively moving the recording medium and the recording medium; a positioning mechanism for irradiating the energy beam to a predetermined location on the recording medium; and a signal processing circuit for changing information to be recorded to a power level of the energy beam. Reading the non-rewritable information recorded on the information recording medium using the information recording medium according to claim 32. Means for decoding at least one of the information of the timing of reaching the second power level and the information of the timing of transitioning from the second power level to another energy level, and storing the second state in the recording medium. Means for modulating an energy pulse in accordance with the decoded timing information when forming the information recording apparatus. 35. An information recording apparatus, comprising: an energy beam generator for generating an energy beam; and a power level of the energy beam set to a first power level and a second power level higher than the first power level. A power adjusting mechanism that can be set, a holding mechanism that holds a recording medium that can be brought into a first state at the first power level, and a second state at the second power level, and the energy beam. A moving mechanism for relatively moving the recording medium and the recording medium; a positioning mechanism for irradiating the energy beam to a predetermined location on the recording medium; and a signal processing circuit for changing information to be recorded to a power level of the energy beam. 26. At least one of the first timing correction method and the second timing correction method according to claim 25, or Means for performing at least one of the first timing correction method and the second timing correction method 28 described, comprises a information recording apparatus.