JP3865123B2 - Optical intensity control device and optical intensity control method for optical disc apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a light intensity control device and a light intensity control method for an optical disc apparatus.
[0002]
[Prior art]
The optical disc, there is a CD-R (Compact Disk-Recordable ) and adds the data recordable write-once optical disc as. In order to record data on the optical disk, the irradiation intensity is set to the recording irradiation intensity, and the optical disk is irradiated with laser light. When the optical disk is irradiated with laser light, pits are formed, and data is represented by pits and lands. In order to reproduce the recorded data, the irradiation intensity is set to the reproduction irradiation intensity, the optical disk is irradiated with the laser beam, the reflected light is received, and an RRF (Read Radio Frequency) signal as a reproduction signal is generated. .
[0003]
When recording data, the irradiation intensity of the laser beam has a great influence on the formation of pits. That is, if the laser beam irradiation intensity is high, the formed pits are large, and if the laser beam irradiation intensity is low, the pits are small. Therefore, in order to reliably reproduce the data, it is necessary to control the recording irradiation intensity of the laser beam.
[0004]
For this reason, when a write-once optical disk is set in the optical disk apparatus, the optical disk apparatus performs OPC (Optimum Power Control) before recording data on the optical disk. This OPC is control for setting the irradiation intensity for recording laser light.
[0005]
When performing OPC, the optical disc apparatus first irradiates the laser beam on a PCA (Power Calibration Area) of the optical disc by changing the irradiation intensity for recording the laser beam stepwise, and records test data on the optical disc. When the test data is recorded, the optical disc apparatus reproduces the recorded test data and obtains an RRF signal.
[0006]
When the RRF signal as shown in FIG. 6 is obtained, the optical disc apparatus obtains the β value from the obtained RRF signal according to the following Equation 1, and determines the quality of the recording state based on the β value.
[Expression 1]
β = ((A−B) / (A + B)) × 100 (%)
However, A: Land side peak value from the center of the RRF signal B: Pit side peak value RRF signal from the center of the RRF signal is defined to have a predetermined signal width such as 3T to 11T, and β The target value is set so that the RRF signal satisfies this rule. A recording state in which the β value obtained based on the RRF signal becomes the target value is an optimum recording state, and an appropriate recording irradiation intensity of the laser beam is obtained based on the target value. .
[0007]
When an appropriate recording irradiation intensity is obtained in OPC, the optical disc apparatus irradiates a program area, which is a user data recording area, with laser light to record user data.
[0008]
Even when user data is recorded in the program area, the optical disc apparatus corrects the recording irradiation intensity of the laser beam so as to obtain an appropriate recording state. Since the β value cannot be obtained at the time of data recording, the optical disc apparatus uses the irradiation intensity for recording the laser beam obtained by OPC to reflect the reflected light from the pit formed by irradiating the optical disc with this irradiation intensity. Correct based on
[0009]
This correction method will be described. When the optical disk apparatus irradiates the irradiation light as shown in FIG. 7A with the irradiation intensity for recording the laser light, pits as shown in FIG. 7B are formed (however, the laser light is irradiated). There is a delay time from when the pit is formed). Then, by receiving the reflected light from the pit, an RF signal having a waveform corresponding to the reflected light as shown in FIG. 7C is obtained.
[0010]
The optical disc apparatus detects a value called Blevel at a sampling timing at which the signal level of the RF signal is stabilized. The conventional optical disk apparatus corrects the recording irradiation intensity of the laser beam so that the detected Blevel becomes substantially constant.
[0011]
[Problems to be solved by the invention]
However, if the Blevel is made substantially constant, if the change in the Blevel is small, the optical disc with less variation in reflectivity and high accuracy can control the irradiation intensity for recording the laser beam to some extent, but the temperature change is large. In this case, or when the reflectance varies, the reflectance of the optical disk changes greatly, and an optimal reproduction level may not be obtained.
[0012]
For example, FIG. 8 shows that an optical disk having a predetermined characteristic is irradiated with a normal recording laser in an environment where the temperature is almost constant, and bits are continuously formed at a predetermined recording speed. ) And Blevel change are measured. As shown in FIG. 8, even if the temperature is constant, the reflectivity is caused by some cause (the cause itself does not need to be specified), for example, when dust or the like adheres to the surface of the optical disk or uneven coating of the dye. As B changes, Blevel also changes and β value also changes. For the same optical disc, as shown in FIG. 9, even if the temperature changes, the temperature change and other causes (there is no need to specify the cause itself), the Blevel changes, and the β value also changes. To do. Since the change in β value indicates a change in the data recording state, an optimum recording state cannot be obtained if the recording state changes depending on the surface state of the optical disk or the temperature. FIG. 9 shows that an optical disk having the same characteristics as in FIG. 8 is irradiated with a normal recording laser in an environment where the temperature changes, and bits are continuously formed at the same recording speed as in FIG. %) And the change in Blevel are measured.
[0013]
The present invention has been made in view of the above-described conventional problems, and is capable of maintaining a stable recording state when data is recorded on a write-once optical disc and a light intensity control device and an optical An object is to provide a strength control method.
[0014]
[Means for Solving the Problems]
In order to achieve this object, a light intensity control device for an optical disc device according to the first aspect of the present invention provides:
In a light intensity control device of an optical disk apparatus for controlling the irradiation intensity of light for recording data by forming pits on a write-once optical disk,
Reference irradiation for setting the irradiation intensity of the irradiation light as the reference irradiation intensity so that the reproduction level of the reproduction signal reproduced based on the data recorded with the pits formed on the optical disc becomes a preset target reproduction level Intensity setting means;
The optical disk is irradiated with light at the reference irradiation intensity set by the reference irradiation intensity setting means, and data is recorded by sequentially forming pits, and reflected from the pits formed by the data recording means Reflected light detecting means for detecting reflected light;
A reflection intensity difference acquisition means for acquiring a reflection intensity difference between a reflection intensity of the reflected light detected by the reflected light detection means and a preset reference reflection intensity;
A correction amount acquisition means for acquiring the irradiation intensity correction amount from the reflection intensity difference acquired by the reflection intensity difference acquisition means according to a preset relationship;
Irradiation intensity correction means for correcting the reference irradiation intensity based on the irradiation intensity correction amount acquired by the correction amount acquisition means.
[0015]
The correction amount acquisition means includes
According to a preset relationship, from the reflection intensity difference acquired by the reflection intensity difference acquisition means, obtain a reproduction level difference from the target reproduction level,
The irradiation intensity correction amount may be acquired from the acquired reproduction level difference according to a preset relationship.
[0016]
The reflected light detection means may detect the reflection intensity of the reflected light based on the reference irradiation intensity from the rear end portion of the pit formed by the data recording means recording data.
[0017]
The reflection intensity difference acquisition means forms a pit in an area for adjusting the irradiation intensity of the data recording irradiation light, and uses the reflection intensity of the reflected light reflected from the pit as a preset reference reflection intensity. You may acquire a reflection intensity difference.
[0018]
The reflection intensity difference acquisition means acquires the reflection intensity difference using the reflection intensity of reflected light from a pit formed first after the data recording means records data as a preset reference reflection intensity. There may be.
[0019]
The optical intensity control method for an optical disc according to the second aspect of the present invention includes:
Setting the irradiation intensity of the irradiation light as a reference irradiation intensity so that the reproduction level of the reproduction signal reproduced based on the data recorded with the pits formed on the optical disk is a preset target reproduction level;
Irradiating the optical disc with light at the set reference irradiation intensity and sequentially recording data by forming pits;
Detecting reflected light reflected from the pits formed by the data recording;
Obtaining a reflection intensity difference between the reflected intensity of the detected reflected light and a preset reference reflection intensity;
Acquiring the irradiation intensity correction amount from the acquired reflection intensity difference according to a preset relationship;
Correcting the reference irradiation intensity based on the acquired irradiation intensity correction amount.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an optical disk device according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows the configuration of the optical disc apparatus according to this embodiment.
The optical disk device is for recording and reproducing data on a write-once type optical disk 1, and includes a spindle motor 11, an optical pickup 12, a driver 13, a thread driver 14, an RF amplifier 15, and a servo circuit. 16, a drive circuit 17, a peak hold circuit (denoted as “P / H” in the figure) 18, a low-pass filter (denoted as “LPF” in the figure) 19, and a bottom hold circuit (in the figure, 20, a sample hold circuit (indicated as “S / H” in the figure) 21, and a microcomputer (hereinafter referred to as “microcomputer”) 22. .
[0021]
The optical disc 1 is a write-once type disc-shaped recording medium such as a CD-R (Compact Disk-Recordable) and a DVD-R (Digital Versatile Disk-Recordable). As shown in FIG. 2, the optical disc 1 has a PCA, a lead-in area, a program area, and a lead-out area from the innermost periphery.
[0022]
PCA is an area for recording and reproducing data by irradiating a laser beam during OPC, obtaining a β value, and setting the irradiation intensity for recording the laser beam. The lead-in area is an area in which TOC (Table Of Contents) indicating track information is recorded. The program area is an area for recording user data such as music data. The lead-out area is an area for ending data reading.
[0023]
Returning to FIG. 1, the spindle motor 11 is a motor for rotating the optical disc 1. The optical pickup 12 is for reading data recorded on the optical disc 1 and includes a laser emitter 31, an objective lens 32, an actuator 33, and a light detector 34.
[0024]
The laser emitter 31 is a light source that emits laser light that irradiates the optical disc 1. The objective lens 32 is a lens for focusing the laser light output from the laser emitter 31 on the recording surface of the optical disc 1 and making the reflected light reflected by the optical disc 1 parallel light. The actuator 33 supports the objective lens 32 so that the position can be adjusted. The light detection unit 34 receives reflected light from the optical disc 1 and outputs an electric signal having a signal level corresponding to the reflection intensity of the reflected light as a light detection signal.
[0025]
The driver 13 is a circuit for controlling the irradiation intensity of the laser beam by controlling the current supplied to the laser emitter 31.
[0026]
The sled drive unit 14 includes a sled motor and the like, and moves the optical pickup 12 so that the laser light is applied to the PCA or the program area of the optical disc 1.
[0027]
The RF amplifier 15 generates an RF (Radio Frequency) signal, an FE (focus error) signal, and a TE (tracking error) signal based on the light detection signal output from the light detection unit 34. The FE signal is a signal indicating an error between the focusing distance when the laser light spot is focused and the distance of the objective lens 32 to the recording surface of the optical disc 1, and the TE signal is the recording surface of the optical disc 1. 1 is a signal showing an error between the center position of the track being read and the position of the light spot. The RF amplifier 15 supplies the generated FE and TE signals to the servo circuit 16.
[0028]
The servo circuit 16 performs phase compensation and gain adjustment based on the FE and TE signals supplied from the RF amplifier 15, and supplies a control signal that brings the signal level of the FE and TE signals close to 0 to the drive circuit 17. Is.
[0029]
The drive circuit 17 controls the actuator 33 based on the control signal supplied from the servo circuit 16.
[0030]
The peak hold circuit 18 is a circuit that detects the peak value of the RRF signal and holds the detected peak value.
The low-pass filter 19 is for acquiring the center value (DC component) of the RRF signal by passing the low-frequency component of the RRF signal.
[0031]
The bottom hold circuit 20 is a circuit that detects the bottom value of the RRF signal and holds the detected bottom value.
The sample hold circuit 21 is a circuit that detects Blevel in reflected light and holds the detected Blevel when recording user data.
[0032]
The microcomputer 22 controls the spindle motor 11, the driver 13, the thread drive unit 14, the RF amplifier 15, and the servo circuit 16 in order to record and reproduce data on the optical disc 1, and the CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory) and the like.
[0033]
Further, the microcomputer 22 calculates a β value at the time of OPC, corrects the recording irradiation intensity of the laser beam based on the Blevel detected at the time of recording the user data, and controls the driver 13 based on the corrected recording irradiation intensity. .
[0034]
Note that the microcomputer 22 stores the Blevel change amount (difference from the detected Blevel from the reference Blevel) and the β change amount as data shown in FIG. (B) the data showing the relationship with (difference from the target value of the predicted value of β), the data showing the relationship between the irradiation intensity for recording the laser beam and β as shown in FIG. As shown, data indicating the relationship between the change amount of β and the correction amount of the recording irradiation intensity of the laser beam is stored.
[0035]
The relationship shown in FIG. 3 is a graph obtained by calculating the change amount of Blevel and the change amount of β value from the relationship between Blevel and β value shown in FIG. 8 or FIG. 9 (Blevel and β value changed). The cause does not matter). Here, the origin where β change amount = 0 and Blevel change amount = 0 indicates that Blevel remains the reference value set in OPC, and β is also a target value.
That is, in FIG. 8 and FIG. 9, the difference between the reference BLEVEL the measured BLEVEL a change in BLEVEL, the difference between β values and the β value when the reference BLEVEL was obtained as a change in the β value As shown, FIG. 3 is obtained.
Further, the relationships shown in FIGS. 4A and 4B are obtained in advance based on experiments and the like. In FIG. 4A, for example, the power of the laser beam for CD-R recording is changed to form a plurality of pits, and for each pit, the laser intensity (power (mW ) when the pits are formed. ) ) And β values are obtained and graphed. Other measurement conditions are the same as the general use conditions of CD-R. FIG. 4 (b) is obtained by modifying FIG. 4 (a), and is a graph showing the correction amount of the laser light intensity necessary for setting each β to zero.
[0036]
The relationship between Blevel and β values illustrated in FIGS. 8 and 9, the characteristics of the disc, so varies the recording speed, the relationship between the change amount and β of variation of Blevel shown in FIG. 3, the recording It is necessary to find out according to the characteristics and recording speed of the disc to be reproduced .
[0037]
Next, the operation of the optical disc apparatus according to the present embodiment will be described.
The spindle motor 11 of the optical disc apparatus rotates the optical disc 1 when the optical disc 1 is set.
[0038]
When the optical disk 1 rotates, the optical disk apparatus first performs OPC to set the irradiation intensity for recording laser light.
When performing OPC, the sled driving unit 14 moves the optical pickup 12 so that the laser beam is irradiated onto the PCA of the optical disc 1.
[0039]
When the optical pickup 12 moves, the driver 13 controls the current to supply a necessary current to the laser emitter 31. The laser emitter 31 emits light when this current flows. The laser beam output from the laser emitter 31 becomes parallel light, is focused on the surface of the optical disc 1 through the objective lens 32, and is irradiated onto the optical disc 1. Thereby, pits are formed on the optical disc 1 and test data is recorded.
[0040]
The driver 13 changes the current step by step every time test data is recorded. As a result, the laser beam recording irradiation intensity changes stepwise, and a plurality of pits corresponding to the laser beam recording irradiation intensity are formed on the PCA of the optical disc 1.
[0041]
Next, the optical disc apparatus reproduces the test data recorded on the PCA.
When reproducing the test data recorded on the PCA, the laser emitter 31 irradiates the optical disc 1 with laser light with the irradiation intensity set to the reproduction irradiation intensity. The objective lens 32 converts the reflected light reflected by the optical disc 1 into parallel light.
[0042]
The light detection unit 34 receives the reflected light and outputs a light detection signal having a signal level corresponding to the reflection intensity to the RF amplifier 15.
[0043]
The RF amplifier 15 generates an RRF signal, an FE signal, and a TLE signal based on the received light detection signal, and supplies the generated FE signal and TE signal to the servo circuit 16.
[0044]
The servo circuit 16 performs phase compensation and gain adjustment based on the FE and TE signals supplied from the RF amplifier 15, and supplies a control signal that brings the signal level of the FE and TE signals close to 0 to the drive circuit 17. .
[0045]
The drive circuit 17 controls the actuator 33 based on the control signal supplied from the servo circuit 16. The actuator 33 adjusts the position of the objective lens 32.
[0046]
The RF amplifier 15 supplies the generated RRF signal to the peak hold circuit 18, the low-pass filter 19, and the bottom hold circuit 20.
[0047]
The peak hold circuit 18 detects and holds the peak value of the RRF signal.
The low pass filter 19 acquires the center value of the RRF signal by allowing only the low frequency component of the RRF signal to pass therethrough.
The bottom hold circuit 20 detects and holds the bottom value of the RRF signal.
[0048]
The microcomputer 22 acquires the peak value, the center value, and the bottom value of the RRF signal from the peak hold circuit 18, the low-pass filter 19, and the bottom hold circuit 20, respectively, and obtains the β value based on these acquired values. The β value is obtained according to the above-described Equation 1.
[0049]
Since a plurality of pits corresponding to the laser beam recording irradiation intensity are formed in the PCA, the microcomputer 22 acquires an optimum β value based on the obtained β value. The microcomputer 22 stores the optimum β value as a target value in the RAM. Then, the microcomputer 22 sets a recording irradiation intensity as a reference based on the target value, and stores the recording irradiation intensity as a reference in the RAM.
[0050]
When the reference recording irradiation intensity is set, the optical disc apparatus records user data in the program area.
[0051]
When recording user data in the program area, the sled driving unit 14 moves the optical pickup 12 so that the laser beam is irradiated onto the program area of the optical disc 1.
[0052]
First, the driver 13 supplies a current to the laser emitter 31 so that the irradiation intensity of the laser light becomes the reference irradiation intensity. The laser emitter 31 irradiates the optical disc 1 with laser light with this recording irradiation intensity.
[0053]
When the optical disc 1 is irradiated with the laser beam with this recording irradiation intensity, pits are formed on the optical disc 1. The light detector 34 receives the reflected light from the first formed pit, and outputs a light detection signal having a signal level corresponding to the reflection intensity of the reflected light to the RF amplifier 15.
[0054]
The RF amplifier 15 generates an RF signal based on the supplied photodetection signal, and supplies the generated RF signal to the sample hold circuit 21. When the RF signal as shown in FIG. 7C is obtained, the sample and hold circuit 21 detects Blevel at the sampling timing in the RF signal and holds the detected Blevel. This Blevel is the first Blevel obtained when recording is actually started at the optimum recording irradiation intensity of the laser beam obtained during OPC. The microcomputer 22 acquires this Blevel from the sample hold circuit 21 and stores the acquired Blevel in the RAM as a reference Blevel.
[0055]
In this way, the optical disc apparatus sequentially records user data in the program area, and pits are sequentially formed in the program area.
[0056]
Each time a pit is formed, the sample hold circuit 21 detects Blevel based on the RF signal, and the microcomputer 22 corrects the recording irradiation intensity serving as a reference of the laser beam based on the detected Blevel.
[0057]
The operation of the microcomputer 22 is shown in the flowchart of FIG.
The microcomputer 22 acquires the detected Blevel from the sample hold circuit 21 (step S11).
[0058]
The microcomputer 22 acquires the reference Blevel from the RAM (step S12).
The microcomputer 22 obtains the difference between the reference Blevel obtained from the RAM and the Blevel obtained from the sample hold circuit 21, and obtains the obtained difference as the Blevel change amount (step S13).
[0059]
The microcomputer 22 acquires the change amount of β from the acquired change amount of Blevel according to the relationship between the change amount of Blevel and the change amount of β value shown in FIG. 3 stored in the ROM (step S14). This change amount of β corresponds to the difference between the predicted value of β when the recorded user data is reproduced and the target value of β stored in the RAM.
[0060]
The microcomputer 22 corrects the laser beam recording irradiation intensity from the β change amount according to the relationship between the β change amount stored in the ROM and the correction amount of the laser beam recording irradiation intensity shown in FIG. An amount is acquired (step S15).
[0061]
The microcomputer 22 corrects the recording irradiation intensity of the reference laser beam stored in the RAM based on the acquired correction amount of the recording irradiation intensity of the laser beam (step S16).
[0062]
Next, the operation of the microcomputer 22 will be described with reference to FIGS.
For example, when the target value of β = 4% (that is, the laser beam recording irradiation intensity = 11.5 mW), the surface state of the optical disk 1 changes or the reflected light from the optical disk 1 changes due to the temperature change. Thus, it is assumed that the Blevel has changed by about −0.5 V compared to the Blevel (reference Blevel) obtained at the beginning when the recording is actually started at the optimum recording irradiation intensity of the laser beam obtained at the OPC. . In this case, from the relationship between the change amount of Blevel and the change amount of β shown in FIG. 3, the β value is changed by about −1.7% from the reference value.
[0063]
The change of the β value by about −1.7% is equivalent to the fact that the recording intensity of the laser beam is decreased from 11.5 mW to 0.375 mW to 11.125 mW as shown in FIG. As shown in (b), it is only necessary to correct the recording irradiation intensity of the laser beam by 0.375 mW. In accordance with the relationship shown in FIG. 4B, the microcomputer 22 corrects the recording irradiation intensity of the reference laser beam so as to increase by about 0.375 mW.
[0064]
The driver 13 supplies a current to the laser emitter 31 based on the corrected recording intensity of the laser beam, and the laser emitter 31 irradiates the optical disc 1 with the laser beam with this recording intensity. Thereby, β is maintained at the target value, and an appropriate recording state is maintained.
[0065]
As described above, according to the present embodiment, Blevel is detected when user data is recorded, the difference between the detected Blevel and the reference Blevel is obtained as a change amount, and the change amount between Blevel and the change amount of β According to the relationship, the difference from the target value of β was obtained as the amount of change, and the irradiation intensity for recording the laser beam was corrected.
[0066]
Therefore, even if the reflectivity of the optical disk 1 changes due to temperature rise, dust, or the like, β can be maintained substantially at the target value, and recording with a stable β value can be performed. Further, the RRF signal has a predetermined signal width, and an appropriate data recording state can be obtained.
[0067]
In carrying out the present invention, various forms are conceivable, and the present invention is not limited to the above-described embodiments.
For example, in the above-described embodiment, the amount of change in β is tested using the relationship between the amount of change in Blevel and the amount of change in β, and the relationship between the amount of change in β and the correction amount of the laser beam recording irradiation intensity I asked for it. However, it is also possible to set mathematical formulas for these relationships and obtain the correction amount of the recording intensity of the laser beam by calculation.
[0068]
Further, in the above embodiment, the reference Blevel is set to the Blevel value obtained first when recording is actually started with the optimum irradiation intensity of the laser beam obtained at the OPC. However, the present invention is not limited to this, and the Blevel detected at the time of OPC can also be set as the reference Blevel. Every time data is recorded in the program area and a pit is formed, the previously detected Blevel is set as the reference Blevel. You can also
[0069]
Also, as shown in FIG. 9, Blevel decreases as the temperature increases, so that the internal temperature of the optical disc apparatus can be grasped using this relationship. A limiter that guarantees the operation of each device can be provided in the optical disc apparatus, the internal temperature can be predicted based on the detected Blevel, and the limiter can be operated.
[0070]
However, as described above, the relationship between the temperature and Blevel shown in FIG. 9 varies depending on the characteristics and recording speed of the disc. Therefore, the relationship between the temperature and Blevel is obtained in advance according to the characteristics and recording speed of the disc. It is necessary to keep.
[0071]
【The invention's effect】
As described above, according to the present invention, a stable recording state can be maintained when data is recorded on a write-once optical disc.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an optical disc apparatus according to an embodiment of the present invention.
FIG. 2 is an explanatory diagram showing an area of an optical disc.
FIG. 3 is an explanatory diagram showing a relationship between a change amount of Blevel and a change amount of β.
4A is an explanatory diagram showing the relationship between the recording irradiation intensity of laser light and β, and FIG. 4B is a graph showing the correction amount of the recording irradiation intensity of laser light and the amount of change in β. It is explanatory drawing which shows a relationship.
FIG. 5 is a flowchart showing an operation of the microcomputer of FIG. 1;
FIG. 6 is an explanatory diagram of an RRF signal.
FIG. 7A is a diagram illustrating laser recording irradiation light, FIG. 7B is a diagram illustrating formed pits, and FIG. 7C is an explanatory diagram illustrating an RF signal during recording.
FIG. 8 is an explanatory diagram showing the relationship between Blevel and β value when the temperature is constant.
FIG. 9 is an explanatory diagram showing the relationship between Blevel and β value when the temperature changes.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Optical disk 13 Driver 15 RF amplifier 18 Peak hold circuit (P / H)
19 Low-pass filter (LPF)
20 Bottom hold circuit (B / H)
21 Sample hold circuit (S / H)
22 Microcomputer

Claims (6)

In a light intensity control device of an optical disk apparatus for controlling the irradiation intensity of light for recording data by forming pits on a write-once optical disk,
Reference irradiation for setting the irradiation intensity of the irradiation light as the reference irradiation intensity so that the reproduction level of the reproduction signal reproduced based on the data recorded with the pits formed on the optical disc becomes a preset target reproduction level Intensity setting means;
Data recording means for recording data by irradiating the optical disc with the reference irradiation intensity set by the reference irradiation intensity setting means and sequentially forming pits;
Reflected light detection means for detecting reflected light reflected from the pits formed by the data recording means;
A reflection intensity difference acquisition means for acquiring a reflection intensity difference between a reflection intensity of the reflected light detected by the reflected light detection means and a preset reference reflection intensity;
A correction amount acquisition means for acquiring the irradiation intensity correction amount from the reflection intensity difference acquired by the reflection intensity difference acquisition means according to a preset relationship;
Irradiation intensity correction means for correcting the reference irradiation intensity based on the irradiation intensity correction amount acquired by the correction amount acquisition means,
A light intensity control device for an optical disk device. The correction amount acquisition means includes
According to a preset relationship, from the reflection intensity difference acquired by the reflection intensity difference acquisition means, obtain a reproduction level difference from the target reproduction level,
In accordance with a preset relationship, the irradiation intensity correction amount is acquired from the acquired reproduction level difference.
The light intensity control device for an optical disc apparatus according to claim 1. The reflected light detection means detects the reflection intensity of the reflected light based on the reference irradiation intensity from the pit rear end portion formed by the data recording means recording data.
The light intensity control device for an optical disc apparatus according to claim 1 or 2, The reflection intensity difference acquisition unit forms a pit in an area for adjusting the irradiation intensity of the data recording irradiation light, and uses the reflection intensity of the reflected light reflected from the pit as a preset reference reflection intensity. To obtain the reflection intensity difference,
4. The light intensity control device for an optical disc apparatus according to claim 1, wherein The reflection intensity difference acquisition means acquires the reflection intensity difference using the reflection intensity of reflected light from a pit formed first after the data recording means records data as a preset reference reflection intensity. is there,
4. The light intensity control device for an optical disc apparatus according to claim 1, wherein Setting the irradiation intensity of the irradiation light as a reference irradiation intensity so that the reproduction level of the reproduction signal reproduced based on the data recorded with the pits formed on the optical disk is a preset target reproduction level;
Irradiating the optical disc with light at the set reference irradiation intensity and sequentially recording data by forming pits;
Detecting reflected light reflected from the pits formed by the data recording;
Obtaining a reflection intensity difference between the reflected intensity of the detected reflected light and a preset reference reflection intensity;
Acquiring the irradiation intensity correction amount from the acquired reflection intensity difference according to a preset relationship;
Correcting the reference irradiation intensity based on the acquired irradiation intensity correction amount,
An optical disc light intensity control method comprising:

Images