JPH05144001A - Method and device for recording optical information - Google Patents

Abstract

PURPOSE:To provide an optical information recording method and device which records information considering thermal interference effects during recording. CONSTITUTION:A main control section 5 switches an analog switch 25, sets respective upper and lower limit values of allowable time width of the detection objects in comparator circuits 36 and 37 so as to detect each time width and obtains the deviations from a reference value. Based on these deviations, time width of reference digital signal A's high levels and low levels are increased or decreased and thus, recorded signals E are generated, laser beams are emitted by these signals E and pits are formed on an optical disk 1. Thus, heat interference effects among pit sections are reduced during information recording and pits, consisting pit sections and non-pit sections whose lengths are corresponding to the reference digital signal time widths, are formed. Moreover, recording and reproducing characteristics are improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is mainly applied to EFM (Eight
The present invention relates to an information recording method for an optical information recording medium such as an optical disc using the to fourteen modulation method and an improvement of the apparatus.

[0002]

2. Description of the Related Art In recent years, a technique for recording a large amount of information on an optical information recording medium, for example, an optical disc such as a WO disc has become popular. In the case of recording an acoustic signal on an optical disc, for example, a method of digitizing the acoustic signal at the time of recording and recording the signal is generally used in order to eliminate distortion, noise, and the like at the time of reproduction. In addition, a CIRC (Cross Interleaved Reed-Solomon Code) is applied to a digitized acoustic signal (hereinafter referred to as a reference digital signal).
With the addition of parity for error correction,
Further, this is modulated by the EFM method to improve the reproduction characteristic.

By performing the above-mentioned EFM modulation, nine time widths, which are 3 to 11 times the predetermined reference time width T, are given as the time widths of the high level and low level of the reference digital signal. The optical disc is irradiated with laser light based on the reference digital signal to form a pit portion in the recording layer. For example, laser light having an intensity capable of forming a pit portion is irradiated during a high level period of the reference digital signal.

Further, when a pit is formed by irradiating the recording layer with laser light on the basis of a reference digital signal to dissolve or alter the recording layer, the recording layer is irradiated with the laser beam when the optical disc is irradiated with laser light. It takes time before heat is absorbed, and it takes time before the heat stored in the recording layer is dissipated when the irradiation of the laser light is stopped. For this reason,
The lengths of the pit portion and the non-pit portion actually formed in the recording layer may not correspond to the time width of the high or low level of the reference digital signal described above, and there is a problem that the reproduction characteristic is deteriorated. It was

That is, as shown in FIG. 2, at the start of laser light irradiation, the integrated value of the laser output increases and it takes time for the heat to be absorbed in the recording layer. The leading edge is formed slightly later than the leading edge of the reference digital signal A.

When the irradiation of the laser light is stopped, the rear end of the pit portion Pa is extended rearward due to the amount of heat energy absorbed in the recording layer and the transfer of heat energy. This tendency is that when the irradiation time of the laser light is long,
That is, since the temperature of the optical disk rises in proportion to time,
When the time width is large, it appears particularly noticeably. In this case, the shape of the pit portion Pa becomes a tear shape and the width of the rear portion of the pit portion widens, and the reflectance decreases and the crosstalk between tracks deteriorates. Invite.

Since the amount of heat energy is small for the one having the shortest time width, the rear end of the pit portion Pa is unlikely to be stretched, but may be too short as compared with other pit portions. ..

Therefore, there is a problem that the deviation of the length of the pit portions Pa caused by the thermal interference between the pit portions Pa increases the jitter and deteriorates the recording / reproducing characteristics.

In order to solve the above-mentioned problems, conventionally, the high-level or low-level time width of the reference digital signal A is uniformly reduced, or the high-level or low-level time of a specific time width is set. A pit composed of a pit portion and a non-pit portion having a length corresponding to the time width of the reference digital signal is generated by generating a recording signal with a changed width and irradiating the optical disc with laser light having a high light intensity by the recording signal. Had formed.

[0010]

However, even if the above-mentioned means is used, it is not possible to completely eliminate the influence of heat, and the recording / reproducing characteristics are low. This is because the high-level or low-level time width of the reference digital signal was uniformly corrected, and the influence of thermal interference between the pit portions was not considered. As a result, the lengths of the pit portion and the non-pit portion having a short length do not correspond to the high-level and low-level time widths of the reference digital signal. Especially, the length of the pit part and the non-pit part corresponding to the minimum time width following the short pit part and the non-pit part, that is, three times the reference time width (hereinafter referred to as 3T time width) is the reference. It does not correspond to the time width of the digital signal.

In view of the above problems, an object of the present invention is to provide an optical information recording method and apparatus for recording information in consideration of the influence of thermal interference during recording.

[0012]

According to claim 1 of the present invention,
A first signal level that corresponds to the information to be recorded and represents a period for irradiating laser light having an intensity capable of forming a pit portion, and a period or laser for irradiating laser light having an intensity lower than the first signal level. A second signal level representing a light irradiation stop period, and the first and second signal levels have a time width forming an arithmetic series that is an integral multiple of a predetermined reference time width. Based on the above, in the optical information recording method of irradiating the optical information recording medium with laser light of a predetermined intensity to form pits, before the formal recording of information, the test area of the optical information recording medium is recorded. After the information is recorded on a trial basis based on the reference digital signal, the step of reproducing the information is repeated a plurality of times to obtain the proper light intensity of the laser, and the laser light of the proper light intensity is obtained. From a pit formed experimentally using The light intensity is detected, the information recorded on the optical information recording medium is reproduced as a digital signal based on the reflected light intensity, and the high-level or low-level time width of the reproduced digital signal is detected. From the time width, after extracting a time width included in a predetermined allowable range centered on a comparison time width of a predetermined multiple of the reference time width, the time width is compared with the comparison time width. Based on the comparison result, at least corresponding to a high level or a low level of the reproduced digital signal,
Further, the increase / decrease value of the time width of the signal level of the reference digital signal having the comparison time width is obtained, and the time width of the signal level of the reference digital signal is corrected using the increase / decrease value when the information is officially recorded. Generate a recording signal,
An optical information recording method is proposed in which laser light is emitted to the optical information recording medium by the recording signal to form pits.

According to a second aspect of the present invention, the first signal level corresponding to the information to be recorded and representing the period for irradiating the laser beam having the intensity capable of forming the pit portion and the laser beam having the intensity lower than the first signal level. A second signal level indicating a laser light irradiation period or a laser light irradiation stop period, and the first and second signal levels have a time width that is an integral multiple of a predetermined reference time width. An optical information recording apparatus that irradiates an optical information recording medium with a laser beam having a predetermined intensity based on a reference digital signal that is provided to form a pit detects the intensity of reflected light from the optical information recording medium. A light intensity detecting means, a signal reproducing means for reproducing the information recorded on the optical information recording medium as a digital signal based on the detection result of the light intensity detecting means, and a high level of the digital signal reproduced by the signal reproducing means. level Or a time width detection means for detecting a low-level time width, and a predetermined tolerance from the time widths detected by the time width detection means centered on a comparison target time width that is a predetermined multiple of the reference time width. Comparison of the time width extraction means for extracting the time width included in the range, the time width comparison means for comparing the time width extracted by the time width extraction means with the comparison target time width, and the time width comparison means Recording signal generation for generating a recording signal corresponding to at least a high level or a low level of the reproduced digital signal and increasing or decreasing the time width of the signal level of the reference digital signal having the comparison time width based on the result. There is proposed an optical information recording apparatus provided with a means and a laser drive control means for controlling the drive of the laser based on the recording signal.

[0014]

According to the first aspect of the present invention, before the formal recording of information, the information is tentatively recorded in the test area of the optical information recording medium based on the reference digital signal, and then the information is reproduced. The process is repeated a plurality of times to determine the proper light intensity of the laser. Further, the intensity of the reflected light from the pit formed experimentally using the laser light of the proper light intensity is detected, and the information recorded on the optical information recording medium is digital signal based on the intensity of the reflected light. And the high-level or low-level time width of the reproduced digital signal is detected, and within the predetermined permissible range centering on the comparison target time width that is a predetermined multiple of the reference time width from the time width. Extract the included time range. Then, the time width is compared with the comparison time width, and the reference corresponding to at least the high level or the low level of the reproduced digital signal based on the comparison result and having the comparison time width. Determine the increase / decrease value of the time width of the signal level of the digital signal. At the time of officially recording information, a recording signal in which the time width of the signal level of the reference digital signal is corrected is generated using the increase / decrease value, and the optical information recording medium is irradiated with laser light by the recording signal. Pits are formed.

According to a second aspect of the present invention, the intensity of the reflected light from the optical information recording medium is detected by the light intensity detecting means when the information is recorded and reproduced on the optical information recording medium on a trial basis. The information recorded on the optical information recording medium is reproduced as a digital signal by the signal reproducing means based on the detection result. Further, the time width detection circuit detects a high-level or low-level time width of the digital signal reproduced by the signal reproduction means, and the time width extraction means selects a predetermined reference time width from the time width. A time width included in a predetermined permissible range centered on the double comparison time width is extracted. Furthermore, by the time width comparison means,
The time width extracted by the time width extracting means is compared with the comparison target time width, and based on the comparison result, the correction time width selecting means corresponds to at least the high level or the low level of the reproduced digital signal. Then, the increase / decrease value of the time width of the signal level of the reference digital signal having the comparison time width is obtained. After that, when formal information recording is performed, the recording signal generation unit corrects the time width of each signal level in the reference digital signal using the increase / decrease value selected by the correction time width selection unit. A signal is generated, and based on the recording signal, the laser driving control means controls the driving of the laser to form a pit on the optical information recording medium.

[0016]

1 is a block diagram of an optical information recording apparatus showing an embodiment of the present invention. In the figure, reference numeral 1 is an optical disk of an optical information recording medium, and as is well known, the optical disk 1 is rotated by a spindle motor or the like (not shown) at the time of information recording.

In addition, the optical information recording apparatus includes a signal conversion section 2,
Time width detection unit 3, main control unit 5, display unit 6, switch unit 7
And a recording unit 8.

The signal converter 2 includes an optical pickup 21 and R.
F amplifier 22, AC coupling 23, inverter 24, 1
It is composed of an analog switch 25 having two circuit contacts and a comparator 26. The optical pickup 21
It is composed of a laser diode, a phototransistor, etc., and irradiates the optical disc 1 with laser light, receives reflected light from the optical disc 1, and outputs a voltage proportional to its light intensity. The RF amplifier 22 outputs a signal RF obtained by amplifying the output signal of the optical pickup 21. This signal RF is AC
After being converted into the signal RF1 by the coupling 23, it is input to the inverter 24 and the first contact 25a of the analog switch 25.

The inverter 24 inputs the signal RF2 obtained by inverting the polarity of the input signal RF1 to the second contact 25b of the analog switch 25. Analog switch 25 contact piece 2
5c is connected to the first or second contact 25a, 25b by the switching signal SEL from the main controller 5, and the signal RF1 or the signal RF2 output from the contact piece 25c is
It is input to the comparator 26. The comparator 26 is
The input signal RF1 or signal RF2 is compared with a predetermined threshold voltage, converted into a digital signal RD having a TTL level voltage, and output.

The time width detector 3 includes a D-type flip-flop 31, a NOT circuit 32, a 16-bit counter 33,
The latch circuit 34, 35, the comparison circuits 36, 37, and the 3-input AND circuit 38 are configured to detect a high-level time width in the signal RD, and the detected time width is set in advance by the main controller 5. When it is within the specified predetermined allowable range, the data of this time width is output.

That is, the signal RD output from the comparator 26 is input to the data input terminal D of the flip-flop 31, and the clock signal C is input to the clock input terminal CLK.
K has been entered. The clock signal CK has a period of 1/8 of the reference time width T in the reference digital signal A described above, for example. Further, the signal RD1 output from the data output terminal Q of the flip-flop 31
Is an enable terminal E and a clear terminal C of the counter 33.
The signal is input to the LR, the first input terminal of the AND circuit 38, and further input to the latch circuit 34 as the signal RD2 inverted by the NOT circuit 32.

Clock signal input terminal CL of the counter 33
The clock signal CK is input to K, the counter 33 counts while the signal RD1 is at a high level, and the counter RD
When 1 becomes low level, it is cleared and operation stops. The 16-bit data DA1 output from the counter 33 is input to the latch circuit 34. The latch circuit 34 is
The input data DA1 is latched at the rising edge of the signal RD2, and the latched data DA2 is output to the latch circuit 35 and the comparison circuits 36 and 37.

The comparator circuit 36 is a 16-bit data D preset by the main controller 5 via the data bus DB.
A11 is compared with the data DA2, and when the value of the data DA2 is smaller than the value of the data DA11, the output signal WD is set to the high level. Further, the comparison circuit 37 has the main control unit 5 in advance.
The 16-bit data DA12 set via the data bus DB is compared with the data DA2, and the data DA2 is compared.
The output signal WU is set to the high level when the value of is higher than the value of the data DA12. These signals WD and WU are logically ANDed with the signal RD by the AND circuit 38, and the output signal WI of the AND circuit 38 is set to the high level when the signals WD, WU and the signal RD are both at the high level, and is input to the latch circuit 35. To be done. The latch circuit 35 receives the data DA input when the signal WI changes from low level to high level.
2 is latched and the latched data DA3 is output to the main controller 5.

As a result, the time width detection unit 3 outputs the value of the time width of the signal RD only when the high level time width of the signal RD is larger than the data DA12 and smaller than the data DA11. It is output to the main controller 5 as DA3.

The main control section 5 is composed of a CPU and the like, and controls display of the display section 6 and drive control of each section based on switch operation of the switch section 7. Also,
The main controller 5 outputs the signal WI and the output data of the latch circuit 35.
The data DA3 is read, and based on the data DA3, the arithmetic processing described later is performed, and the correction data DAT is output to the recording signal generation circuit described later. Further, the switch section 7 is a recording switch, a data
It is equipped with a momentary switch such as a selector switch and a reset switch.

The recording section 8 is composed of an EFM encoder 81, a recording signal generation circuit 82, a laser drive control circuit 83 and a laser diode 84. The EFM encoder 81 EFM-modulates the digital information to be recorded and outputs it as a reference digital signal A to a recording signal generating circuit 82, and the recording signal generating circuit 82 outputs the high-level and low-level time of the reference digital signal A. The width is corrected and output as a signal E to the laser drive control circuit 83. Ray
The drive control circuit 83 outputs laser light when the signal E is at high level.
A predetermined current is passed through the diode 84 to emit laser light having a high light intensity capable of forming a pit portion in the recording layer of the optical disk. Further, when the recording signal E is low level, laser light is emitted.
A current for emitting laser light of low light intensity capable of forming a non-pit portion is supplied to the diode 84, or the supply of current to the laser diode 84 is stopped.

The recording signal generating circuit 82 is a reference digital signal A corresponding to the information to be recorded on the optical disc 1.
And a clock signal CP synchronized with this are input to generate a recording signal E in which the reference digital signal A is corrected based on the correction data DAT, and the recording signal E is passed through the laser drive control circuit 83. Then, the laser diode 84 is driven to record information on the optical disc 1. Here, the clock signal CP has a period equal to the reference time width T, and as the optical disc 1, for example, a recording layer is formed by a cyanine dye on a substrate on which a tracking groove is formed, and this recording layer is further formed. An optical disc having a gold reflective layer and a protective layer made of an ultraviolet curable resin formed on it is used. Further, when the reference digital signal A is at a high level, the optical disc is irradiated with high-intensity laser light capable of forming a pit portion, and when at a low level, a low-intensity laser light capable of forming a non-pit portion is generated. Irradiate the optical disk or
It is set to stop the irradiation of the light and form pits on the optical disc 1.

As shown in FIG. 3, the recording signal generating circuit 82 includes a trailing edge pulse generating circuit 100 and a plurality of delay circuits 201-20.
8. A voltage control circuit 300 and a signal synthesis circuit 400 are included. The trailing edge pulse generation circuit 100 detects the high-level and low-level time widths of the reference digital signal A based on the clock signal CP, and the high-level time width is 3 to 6 times the reference time width T. At this time, the positive pulse signals P3 to P6 having the reference time width T are output corresponding to each time width, and the low-level time width is 3 to 6 of the reference time width T.
When it is doubled, the positive pulse signals L3 to L6 having the reference time width T are output corresponding to each time width. Hereinafter, a time width that is n times the reference time width T is referred to as an nT time width.

The trailing edge pulse generation circuit 100 includes a shift register 111, NOT circuits 112 to 118, and 4-input AND circuits.
The shift register 111 includes circuits 119 to 126. The clock signal CP is input to the clock input terminal CLK of the shift register 111, and the reference digital signal A is input to the serial data input terminal AB.

The output terminal Qa of the shift register 111 is A
The AND circuit 119 is connected to the respective first input terminals of the ND circuits 123 to 126 and via the NOT circuit 112.
To 122 first input terminals.
The output terminal Qb of the shift register 111 is connected to the AND circuit 119.
~ 122 second input terminals and signal combining circuit 40
It is connected to 0 and ANDed through the NOT circuit 113.
Connected to the second input terminals of each of the circuits 123-126. The output terminal Qd of the shift register 111 is AND
It is connected to the third input terminal of the circuit 119 and is NOT
It is connected to the third input terminal of the AND circuit 123 via the circuit 114. The output terminal Qe of the shift register 111 is
AND circuit 123 connected to the third input terminal of AND circuit 120
Connected to the fourth input terminal of the NOT circuit 115
Is connected to the fourth input terminal of the AND circuit 119 and the third input terminal of the AND circuit 124. The output terminal Qf of the shift register 111 is connected to the third input terminal of the AND circuit 121 and the fourth input terminal of the AND circuit 124, and is also connected to the fourth input terminal of the AND circuit 120 via the NOT circuit 116. It is connected to the third input terminal of the AND circuit 125. The output terminal Qg of the shift register 111 is
It is connected to the third input terminal of the AND circuit 122 and the fourth input terminal of the AND circuit 125, and is also connected to the fourth input terminal of the AND circuit 121 via the NOT circuit 117 and the AND circuit.
It is connected to the third input terminal of 126. The output terminal Qh of the shift register 111 is connected to the fourth input terminal of the AND circuit 126 and is connected to the AN via the NOT circuit 118.
It is connected to the fourth input terminal of the D circuit 122.

As a result, the high-level time width of the reference digital signal A is three times, four times, five times, or 6 times the reference time width T.
When doubled, the AND circuits 119, 120, 121 and 122 output pulse signals P3, P4, P5 and P6, respectively. When the low-level time width of the reference digital signal A is three times, four times, five times, or six times the reference time width T, the AND circuits 123, 124, 125, 126 output pulse signals L3, L4, L5.
L6 is output respectively.

As shown in FIG. 4, each of the delay circuits 201 to 208 includes NPN type transistors 211, 212 and NOT.
It is composed of circuits 213 and 214, a diode 215, resistors R1 to R3, and a capacitor C1, and a predetermined positive voltage + V1, for example + 5V, is applied to the collector of the transistor 211, and the base is connected via the resistor R1. AND circuit 119-12
Connected to each of the 6 output terminals. Further, a capacitor C1 is connected between the emitter and collector of the transistor 211, and the emitter is the collector of the transistor 212, the cathode of the diode 215 and the NO.
It is connected to the input terminal of the T circuit 213. Diode 21
The node 5 is grounded, and the output terminal of the NOT circuit 213 is connected to the input terminal of the NOT circuit 214. A predetermined negative voltage -V2, for example, -5V is applied to the emitter of the transistor 212 via the resistor R2, and the base is connected to one end of the resistor R3. Further, the voltage control circuit 300 applies predetermined voltages vh3 to vh6 and vl3 to vl6 to the other end of the resistor R3.

As a result, in the delay circuits 201-208, from the rear end pulse generation circuit 100 to the delay circuits 201-208.
The ON / OFF state of the transistor 211 is switched by the pulse signals P3 to P6 and L3 to L6 inputted to the pulse signal P3 to P6.
The rear end of P6, L3 to L6 is a predetermined time th3 to th6, t
Positive pulse signals Pd3 to P delayed by l3 to tl6
d6, Ld3 to Ld6 are output.

That is, as shown in FIG. 5, the pulse signal P3
~ P6, L3 ~ L6 are input and the base voltage Vb of the transistor 211 becomes high level, the transistor 211
Is turned on, the capacitor C1 is discharged, and
The input voltage Vin of the NOT circuit 213 becomes the voltage + V1, and N
The output voltage Vout of the OT circuit 214 becomes high level. When the base voltage Vb of the transistor 211 becomes low level, the transistor 211 is turned off and the capacitor C1 has a base voltage of the transistor 212 and a resistor R3.
A current flows based on the resistance value of the capacitor C1, and the charging of the capacitor C1 is started. As a result, the input voltage V of the NOT circuit 213
The in gradually decreases as the charging of the capacitor C1 progresses, and when the voltage becomes equal to or lower than the threshold voltage of the NOT circuit 213, NO
The output voltage Vout of the T circuit 214 becomes low level.

The voltage control circuit 300 is composed of, for example, a register for holding the correction data DAT input from the main control unit 5, a plurality of resistors and an analog switch, and each delay based on the correction data DAT. The values of the control voltages vh3 to vh6 and vl3 to vl6 output to the circuits 201 to 208 are changed.

The signal synthesizing circuit 400 is a three-input OR circuit 40.
1 to 403, 3-input AND circuits 404, 405, 2-input AN
The D circuit 406 includes a 2-input NOR circuit 407 and 2-input OR circuits 408 and 409. The first input terminal of the OR circuit 401 is grounded, and the second and third input terminals are connected to the output terminals of the NOT circuits 214 of the delay circuits 201 and 202, respectively. The first input terminal of the OR circuit 402 is grounded, and each of the second and third input terminals has a delay circuit 203,
It is connected to the output terminal of the NOT circuit 214 of 204.

The first input terminal of the OR circuit 403 is
It is connected to the output terminal Qb of the shift register 111 of the rear end pulse generation circuit 100 via the AND circuits 404 and 405 connected in series. That is, the three input terminals of the AND circuit 404 are both connected to the output terminal Qb of the shift register 111,
The output terminal of the AND circuit 404 is connected to the three input terminals of the AND circuit 405, and the output terminal of the AND circuit 405 is connected to the first input terminal of the OR circuit 403. OR
The second and third input terminals of the circuit 403 are OR circuits, respectively.
The output terminals of the OR circuit 403 are connected to the output terminals of 401 and 402, and the first input terminal of the AND circuit 406 is connected. The second input terminal of the AND circuit 406 is the NOR circuit 407.
, And the two input terminals of the NOR circuit 407 are connected to the output terminals of the ORD circuits 408 and 409, respectively. The two input terminals of the OR circuit 408 are connected to the output terminals of the NOT circuit 214 of the delay circuits 205 and 206, respectively, and the two input terminals of the OR circuit 409 are the delay circuits 207 and 206.
They are connected to the output terminals of 208 NOT circuits 214, respectively. Further, the output terminal of the AND circuit 406 is connected to the laser diode 84 via the laser drive control circuit 83.

The resistance values of the resistors and the capacitance of the capacitor C1 in each of the delay circuits 201 to 208 described above are set to appropriate values obtained in advance by experiments or the like.

Next, the operation of this embodiment having the above-described structure will be described with reference to the timing charts shown in FIGS. 6 to 9, the flow chart shown in FIGS. 10 to 13, and the setting data shown in FIG. Table, the control voltage selection table shown in FIG. In the signal conversion unit 2, the time width detection unit 3, and the main control unit 5, the time width in the reproduction signal based on the pit portion and the non-pit portion experimentally formed on the optical disc 1 is smaller than the time width in the reference digital signal A. The amount of deviation is detected, and based on this detection result, a correction value for the high-level and low-level time width of the reference digital signal A at the time of recording information on the optical disc 1 is selected.

In the present embodiment, the high-level and low-level time widths in the reference digital signal A corresponding to the pit portion and the non-pit portion having a small time width where the influence of thermal interference is relatively likely to appear are corrected. Actually, the high-level and low-level time widths having a time width 3 to 6 times the reference time width T are corrected.

Further, when selecting the correction value, the light intensity of the laser that is optimum for the formation of pits on the optical disc 1 is obtained in advance, and the reproduction signal from the pits formed on the optical disc 1 is determined by this optimum light intensity. , The intensity of the laser light is set to the optimum light intensity even when the information is recorded by the recording signal generated based on the correction value.
The time width detection unit 3 and the main control unit 5 operate as follows.

A non-pit portion Pb having a predetermined time width, for example, 4
When detecting the deviation of the high-level time width in the reproduction signal RF corresponding to the non-pit portion Pb of the T time width, the main control unit 5 switches the analog switch 25 by the switching signal SEL to make the comparator 26. The signal RF1 is input, and the comparison circuit 36 is supplied via the data bus DB.
To the comparator circuit 37, and the lower limit value data DA12 of the 4T time width to the comparison circuit 37.
Are set respectively and the detection process is started.

As a result, as shown in the timing chart of FIG. 6, the output signal RF of the RF amplifier 22 is AC-coupled and input to the comparator 26. In this case, in the signal RF1, the reflected light intensity from the non-pit portion Pb has a positive voltage, and the reflected light intensity from the pit portion Pa has a negative voltage.

On the other hand, the count value DA1 of the counter 33 is latched by the latch circuit 34 at the trailing edge of the signal RD1 transiting from the high level to the low level, and the latched data DA2 falls next to the signal RD1. Held up to. The data DA2 output from the latch circuit 34 is compared with the upper limit value DA11 and the lower limit value DA12 of the 4T time width by the comparison circuits 36 and 37, and the value of the data DA2 is the upper limit value DA11 and the lower limit value DA12. Within range and signal R
When D1 is at high level, the signal WI is at high level. The data DA2 is latched in the latch circuit 35 by the rising of the signal WI. Therefore, only the data DA2 having a time width within the allowable range of the 4T time width is latched by the latch circuit 3.
The data DA3 latched by the latch circuit 5 and output from the latch circuit 35 is read by the main controller 5.

When detecting a low level time width deviation in the reproduction signal RF corresponding to a pit portion Pa having a predetermined time width, for example, a pit portion Pa having a 5T time width,
The main control unit 5 switches the analog switch 25 by the switching signal SEL to send the signal RF2 to the comparator 26.
And the comparator circuit 3 via the data bus DB.
6 for 5T time width upper limit data DA11, and for the comparison circuit 37 for 5T time width lower limit data DA11.
Set 12 respectively and start the detection process.

As a result, as shown in the timing chart of FIG. 7, the output signal RF of the RF amplifier 22 is AC-coupled, then inverted, and input to the comparator 26. In this case, in the signal RF2, the non-pit portion Pb
The intensity of reflected light from is a negative voltage, and the intensity of reflected light from the pit portion Pa is a positive voltage. The subsequent operation is similar to that described above.

The permissible range and the center value for each of the above-mentioned time intervals of 3T to 6T are set in advance as shown in FIG. For example, the allowable range of 3T time width is 2.5T or more and less than 3.5T, and the center value is 3.0.
When T is converted into the count value of the counter 33, the data DA11 becomes 27 in decimal number and the data DA112 becomes 19 in decimal number, and these values are set when detecting each time width. ..

Next, the processing operation of the main controller 5 will be described based on the flowcharts shown in FIGS. The main controller 5 constantly monitors whether the data selection switch, the recording switch or the reset switch is turned on (S
1, S2, S3), when the data selection switch is turned on, the variable n is set to 3, the variable CN is set to 0, and the variable NH3 is set.
~ NH6, NL3 to NL6 are set to 0 respectively (S
4, S5, S6), the analog switch 25 is switched by the switching signal SEL, and the signal R is sent to the comparator 26.
Input F1 (S7). As a result, the non-pit portion Pb
It is possible to detect the time width of the reproduction signal corresponding to.

Next, the main controller 5 compares the window data DA11 and DA12 for nT time width detection with the comparators 36 and 37.
(S8), it is determined whether the pulse signal WI is input from the time width detection unit 3 (S8).
9). As a result of this determination, when the pulse signal WI is input, the main control section 5 outputs the output data DA3 of the latch circuit 35.
Is read (S10), and the value of this data DA3 is set to the variable NL.
At the same time as adding to n (S11), 1 is added to the variable CN (S12), and it is determined whether or not the variable CN exceeds a predetermined constant K, for example 100 (S13). As a result of this judgment,
When the variable CN does not exceed the constant K, the process proceeds to S9, and when it exceeds, it is determined whether the variable n is equal to 6 (S14). As a result of this determination, when the variable n is not equal to 6, 1 is added to the variable n (S15), the variable CN is set to 0 (S16), and the process proceeds to S8. Further, when the variable n is equal to 6, the variable n is set to 3
, The variable CN is set to 0 (S17, S18), and the analog switch 25 is activated by the switching signal SEL.
And the signal RF2 is input to the comparator 26 (S19). Thereby, the time width of the reproduction signal corresponding to the pit portion Pa can be detected.

Next, the main controller 5 compares the window data DA11, DA12 for nT time width detection with the comparators 36, 37.
(S20), it is determined whether the pulse signal WI is input from the time width detection unit 3 (S2).
1). As a result of this determination, when the pulse signal WI is input, the main control section 5 outputs the output data DA3 of the latch circuit 35.
Is read (S22), and the value of this data DA3 is set to the variable NH.
At the same time as adding to n (S23), 1 is added to the variable CN (S24), and it is determined whether or not the variable CN exceeds a predetermined constant K (S25). As a result of this determination, when the variable CN does not exceed the constant K, the process proceeds to S21, and when it exceeds, it is determined whether the variable n is equal to 6 (S2
6). If the result of this determination is that the variable n is not equal to 6, 1 is added to the variable n (S28) and the variable CN
Is set to 0 (S29), and the process proceeds to S8. Further, when the variable n is equal to 6, the variables NL3 to N
A value obtained by dividing each of L6, NH3 to NH6 by a constant K is calculated, and the corresponding variables ML3 to ML6 and MH3 to M are calculated.
It sets to each of H6 (S30). Thereby, the reproduction signal RF corresponding to the non-pit portion Pb and the pit portion Pa
The average value for each time width of the high level and the low level in is calculated.

After that, the main control section 5 obtains a correction value for each time width of the high level and the low level of the reference digital signal. That is, the main control unit 5 determines whether or not the value of the variable MH3 is equal to or greater than the count value 23 of the counter 33 corresponding to the time width three times the reference time width T (S31), and the variable MH3.
When the value of is greater than or equal to 23, it is determined whether the value of the variable ML3 is greater than or equal to 23 (S32). As a result of this judgment, when the value of the variable ML3 is 23 or more, the correction values tl3, t for the low-level and high-level time widths having the time width three times the reference time width T in the reference digital signal A are obtained.
h3 is set to 0 (S33), and S42 described later is executed.
Process shifts to.

As a result of the determination in S32, when the value of the variable ML3 is less than 23, the main control section 5 has a 3T time width in the reference digital signal A by subtracting the value of the variable ML3 from 23. Correction value tl for low level
3, the correction value th3 for the high level having the 3T time width is set to 0 (S34), and the process proceeds to S42 described later.

When the value of the variable MH3 is less than 23 as a result of the determination in S31, it is determined whether the value of the variable ML3 is 23 or more (S35). As a result of this determination, when the value of the variable ML3 is 23 or more, the main control unit 5 returns 23
The value obtained by subtracting the value of the variable MH3 from is set to the correction value th3 for the high level time width having the 3T time width in the reference digital signal A, and the correction value tl3 for the low level having the 3T time width is set to 0 (S36). Then, the processing shifts to S42 described later.

As a result of the determination in S35, the variable ML
When the value of 3 is less than 23, the main control unit 5 sets the variable MH.
It is determined whether the value of 3 and the value of the variable ML3 are equal (S3
7) When the value of the variable MH3 and the value of the variable ML3 are equal, the value obtained by subtracting the value of the variable MH3 from 23 is respectively for the high-level and low-level time widths having the 3T time width in the reference digital signal A. Correction value th3
, Tl3 (S38), and the processing shifts to S42 described later.

When the value of the variable MH3 is not equal to the value of the variable ML3 as a result of the determination in S37, the main control section 5 determines whether the value of the variable MH3 is larger than the value of the variable ML3 (S39). ). As a result of this determination, when the value of the variable ML3 is equal to or more than the value of the variable MH3, the main control unit 5 subtracts the value of the variable MH3 from 23, and sets the value at the high level time having the 3T time width in the reference digital signal A. The correction value th3 for the width is set to 0, and the correction value tl3 for the low level having the 3T time width is set to 0 (S40).
The process shifts to 2. The value of the variable MH3 is the variable ML.
When it is larger than the value of 3, the value obtained by subtracting the value of the variable ML3 from 23 is set as the correction value tl3 for the low level time width having the 3T time width in the reference digital signal A, and the high level having the 3T time width. Correction value for
3 is set to 0 (S41).

Next, the main controller 5 determines whether or not the value of the variable MH4 is equal to or larger than the count value 31 of the counter 33 corresponding to the 4T time width (S42), and the value of the variable MH4 is 31.
In the above case, it is determined whether the value of the variable ML4 is 31 or more (S43). As a result of this judgment, when the value of the variable ML4 is 31 or more, the correction values tl4 and th4 for the low-level time width and the high-level time width having the 4T time width in the reference digital signal A are set to 0 (S44). Then, the processing shifts to S53 described later.

As a result of the determination in S43, when the value of the variable ML4 is less than 31, the main control section 5 has a value obtained by subtracting the value of the variable ML4 from 31 to have a 4T time width in the reference digital signal A. Correction value tl for low level
4, the correction value th4 for the high level having the 4T time width is set to 0 (S45), and the process proceeds to S53 described later.

As a result of the determination in S42, if the value of the variable MH4 is less than 31, it is determined whether the value of the variable ML4 is 31 or more (S46). As a result of this determination, when the value of the variable ML4 is 31 or more, the main control unit 5 determines
The value obtained by subtracting the value of the variable MH4 from is set to the correction value th4 for the high level time width having the 4T time width in the reference digital signal A, and the correction value tl4 for the low level having the 4T time width is set to 0 (S47). Then, the processing shifts to S53 described later.

As a result of the determination in S46, the variable ML
When the value of 4 is less than 31, the main controller 5 sets the variable MH.
4 is equal to the value of the variable ML4 (S4
8) When the value of the variable MH4 and the value of the variable ML4 are equal, the value obtained by subtracting the value of the variable MH4 from 31 is respectively for the high-level and low-level time widths having the 4T time width in the reference digital signal A. Correction value th4
, Tl4 (S49), and the process proceeds to S53 described later.

When the value of the variable MH4 is not equal to the value of the variable ML4 as a result of the determination in S48, the main control section 5 determines whether the value of the variable MH4 is larger than the value of the variable ML4 (S50). ). As a result of this determination, when the value of the variable ML4 is equal to or more than the value of the variable MH4, the main control unit 5 subtracts the value of the variable MH4 from 31 and sets the high level time having the 4T time width in the reference digital signal A to the high level time. A correction value th4 for the width is set, and a correction value tl4 for the low level having a 4T time width is set to 0 (S51).
The process moves to 3. Also, the value of the variable MH4 is the variable ML.
When it is larger than the value of 4, the value obtained by subtracting the value of the variable ML4 from 31 is set as the correction value tl4 for the low level time width having the 4T time width in the reference digital signal A, and the high level having the 4T time width. Correction value tl for
4 is set to 0 (S52).

Next, the main controller 5 determines whether or not the value of the variable MH5 is equal to or greater than the count value 39 of the counter 33 corresponding to the 5T time width (S53), and the value of the variable MH5 is 39.
In the above case, it is determined whether the value of the variable ML5 is 39 or more (S54). As a result of this judgment, when the value of the variable ML5 is 39 or more, the correction values tl5 and th5 for the low-level and high-level time widths having the 5T time width in the reference digital signal A are set to 0 (S55). Then, the processing shifts to S64 described later.

As a result of the determination in S54, when the value of the variable ML5 is less than 39, the main control section 5 has a value obtained by subtracting the value of the variable ML5 from 39 to have a 5T time width in the reference digital signal A. Correction value tl for low level
5, the correction value th5 for the high level having the 5T time width is set to 0 (S56), and the process proceeds to S64 described later.

When the value of the variable MH5 is less than 39 as a result of the determination in S53, it is determined whether the value of the variable ML5 is 39 or more (S57). As a result of this determination, when the value of the variable ML5 is 39 or more, the main control unit 5 causes 39
The value obtained by subtracting the value of the variable MH5 from is set to the correction value th5 for the high level time width having the 5T time width in the reference digital signal A, and the correction value tl5 for the low level having the 5T time width is set to 0 (S58). Then, the processing shifts to S64 described later.

Further, as a result of the determination in S57, the variable ML
When the value of 5 is less than 39, the main control unit 5 sets the variable MH.
It is determined whether the value of 5 and the value of the variable ML5 are equal (S5
9) When the value of the variable MH5 and the value of the variable ML5 are equal, the value obtained by subtracting the value of the variable MH5 from 39 is respectively for the high-level and low-level time widths having the 5T time width in the reference digital signal A. Correction value th5
, Tl5 (S60), and the processing shifts to S64 described later.

When the value of the variable MH5 is not equal to the value of the variable ML5 as a result of the determination in S59, the main controller 5 determines whether the value of the variable MH5 is larger than the value of the variable ML5 (S61). ). As a result of this determination, when the value of the variable ML5 is equal to or more than the value of the variable MH5, the main control unit 5 subtracts the value of the variable MH5 from 39 and sets the value at the high level time having the 5T time width in the reference digital signal A. The correction value th5 for the width is set to 0, and the correction value tl5 for the low level having the 5T time width is set to 0 (S62).
The process shifts to the process of No. 4. Further, the value of the variable MH5 is the value of the variable ML.
When it is larger than the value of 5, the value obtained by subtracting the value of the variable ML5 from 39 is set as the correction value tl5 for the low-level time width having the 5T time width in the reference digital signal A, and the high level having the 5T time width. Correction value for
5 is set to 0 (S63).

Next, the main controller 5 determines whether or not the value of the variable MH6 is greater than or equal to the count value 47 of the counter 33 corresponding to the 6T time width (S64), and the value of the variable MH6 is 47.
In the above case, it is determined whether or not the value of the variable ML6 is 47 or more (S65). As a result of this judgment, when the value of the variable ML6 is 47 or more, the correction values tl6 and th6 for the low-level and high-level time widths having the 6T time width in the reference digital signal A are set to 0 (S66). Then, the process proceeds to S75 described later.

As a result of the determination in S65, when the value of the variable ML6 is less than 47, the main control section 5 has a 6T time width in the reference digital signal A by subtracting the value of the variable ML6 from 47. Correction value tl for low level
6, the correction value th6 for the high level having the 6T time width is set to 0 (S67), and the process proceeds to S75 described later.

When the value of the variable MH6 is less than 47 as a result of the determination in S64, it is determined whether the value of the variable ML6 is 47 or more (S68). As a result of this determination, when the value of the variable ML6 is 47 or more, the main control unit 5 sets the value to 47.
The value obtained by subtracting the value of the variable MH6 from is set as the correction value th6 for the high level time width having the 6T time width in the reference digital signal A, and the correction value tl6 for the low level having the 6T time width is set to 0 (S69). Then, the process proceeds to S75 described later.

As a result of the determination in S68, the variable ML
When the value of 6 is less than 47, the main controller 5 sets the variable MH.
It is determined whether or not the value of 6 and the value of the variable ML6 are equal (S7
0), when the value of the variable MH6 is equal to the value of the variable ML6, the value obtained by subtracting the value of the variable MH6 from 47 is respectively applied to the high-level and low-level time widths having the 6T time width in the reference digital signal A. Correction value th6
, Tl6 (S71), and the process proceeds to S75 which will be described later.

When the value of the variable MH6 is not equal to the value of the variable ML6 as a result of the determination in S70, the main control section 5 determines whether the value of the variable MH6 is larger than the value of the variable ML6 (S72). ). As a result of this determination, when the value of the variable ML6 is equal to or more than the value of the variable MH6, the main control unit 5 subtracts the value of the variable MH6 from 47 and sets the value at the high level time having the 6T time width in the reference digital signal A. The correction value th6 for the width and the correction value tl6 for the low level having the 6T time width are set to 0 (S73), and S7 to be described later.
The process moves to step 5. Further, the value of the variable MH6 is the variable ML.
When it is larger than the value of 6, the value obtained by subtracting the value of the variable ML6 from 47 is used as a correction value tl6 for the low level time width having the 6T time width in the reference digital signal A.
And a correction value th for a high level having a 6T time width
6 is set to 0 (S74).

Next, the main control section 5 determines each of the correction values tl3.about. Based on the preset control voltage selection table.
control voltage values vl3 to v6 corresponding to tl6 and th3 to th6
l6 and vh3 to vh6 are selected and stored in the memory provided in the main controller 5 (S75). Here, as shown in the control voltage selection table of FIG. 15, the control voltage values vl3 to vl6, vh3 to vh6 depend on which of the five selected values the correction values tl3 to tl6, th3 to th6 correspond to. Has been selected. That is, when the correction values tl3 to tl6 and th3 to th6 are 0, 1, 2, 3, and 4, the corresponding control voltage values vl3 to vl6 and vh3 to vh6 are VA, VB, and V, respectively.
C, VD and VE are selected.

Next, the main control section 5 turns on the selection end lamp of the display section 6 for a predetermined time (S76), and thereafter, the above-mentioned S
The processing shifts to 1.

When the recording switch is turned on as a result of the determination in S2, the main control section 5 outputs the control voltage values vl3 to vl6 and vh3 to vh6 stored in the memory to the recording signal generating circuit 82. Set in the voltage control circuit 300 (S7
7). As a result, the recording signal generation circuit 82 generates the recording signal E in which the high-level or low-level time width of the reference digital signal A is corrected.
Information is recorded on the optical disc 1 in accordance with.

That is, the recording signal generating circuit 82 operates as follows. Each of the pulse signals P3 to P6 and L3 to L6 output from the rear end pulse generation circuit 100 is, as shown in FIGS. 8 and 9, an output terminal Qb of the shift register 111.
2 from the signal output from the reference digital signal A
It corresponds to the signal B delayed by the clock pulse CP, and the rear ends of the pulse signals P3 to P6 are the high level rear ends having a time width 3 to 6 times the reference time width T of the reference digital signal A. Match and pulse signals L3 to L6
The trailing end is output so as to coincide with the trailing end of the low level having a time width of 3 to 6 times the reference time width T in the reference digital signal A. Further, these pulse signals P3 to P
The time widths of 6, L3 to L6 are equal to the reference time width T.

Each of the pulse signals P3 to P6 and L3 to L6 output from the trailing edge pulse generation circuit 100 is delayed by the corresponding delay circuits 201 to 208, as described above, and the trailing edge of each of the pulse signals P3 to P6 and L3 to L6. The output is delayed by tl3 to tl6.

After that, the signal synthesizing circuit 400 synthesizes the pulse signals Pd3 to Pd6, Ld3 to Ld6 and the signal B, and inputs them as the signal E to the laser drive control circuit 2. That is, in the signal synthesis circuit 400, the pulse signal Pd
3 to Pd6 are logically ORed with the signal B by the OR circuits 401 to 403 to obtain the signal D. This gives at signal D
The high-level time width having a time width of 3 to 6 times the reference time width T is lengthened by the times th3 to th6, respectively, and the low-level time width following them is shortened accordingly.

Further, the signal D is logically ANDed by the AND circuit 406 with a signal obtained by further inverting the signal obtained by logically adding the pulse signals Ld3 to Ld6, and output as a recording signal E. As a result, the trailing end portions of the low level having a time width 3 to 6 times the reference time width T in the recording signal E are extended by the time tl3 to tl6, respectively, and the time width of the high level following them is shortened by that amount. To be extinguished. This recording signal E
Is input to the laser drive control circuit 83.

The laser drive control circuit 83 causes a predetermined current to flow through the laser diode 84 when the recording signal E is at a high level, so that the laser of high light intensity can form a pit portion in the recording layer of the optical disk. It emits light and the recording signal E is low.
When the level is reached, the laser diode 84 is energized with a current for emitting laser light of low light intensity capable of forming a non-pit portion, or the energization of the laser diode 84 is stopped.

When the reset switch is turned on as a result of the determination in S3, the main control section 5 erases the correction value stored in the memory (S78), and shifts to the processing in S1.

Therefore, according to this embodiment, the main controller 5
Is a reproduction signal RF corresponding to the pit portion Pa and the non-pit portion Pb having a time width of 3T to 6T in which the influence of thermal interference appears significantly.
Since the set value of the control voltage to the voltage control circuit 300 is changed on the basis of the low-level and high-level time widths, the high-level or low-level time width of the reference digital signal A is individually changed. It is possible to reduce the influence of thermal interference between pit portions during information recording, and it is possible to form pits having pit portions and non-pit portions having a length corresponding to the time width of the reference digital signal A. This allows
Since the recording / reproducing characteristics can be improved and the intensity of the laser light at the time of recording can be set low, double speed recording can be performed. In addition, the optical pickup 21,
Even if the wavelength of the diode 84, the wavelength of the laser light, or the type of the optical disk 1 is changed, it can be immediately dealt with, and a high recording / reproducing characteristic can always be maintained.

In this embodiment, the reference digital signal A
The recording signal E in which the high-level time width and the low-level time width, which are 3 to 6 times the reference time width T, are changed
However, the present invention is not limited to this, and the correction target may be changed as necessary.

Further, in the present embodiment, the high-level or low-level time width of the reference digital signal is increased and corrected, but the time width may be decreased or corrected. After the level time width is uniformly reduced, each time width may be increased and corrected.

Further, the circuit configuration of this embodiment is an example,
It goes without saying that the present invention is not limited to this.

[0084]

As described above, according to the first aspect of the present invention.
According to the method, the time width of the first signal level of the reference digital signal is corrected based on each time width detected from the reproduction signal from the pit portion and the non-pit portion formed on the optical information recording medium for information recording. Since the recorded signal is generated and the optical information recording medium is irradiated with laser light by the recorded signal to form pits, it is possible to reduce the influence of thermal interference between the pit portions during information recording. Therefore, it is possible to form a pit having a pit portion and a non-pit portion having a length corresponding to the time width of the reference digital signal. As a result, the recording / reproducing characteristics can be improved, and the intensity of the laser light at the time of recording can be set low, so that double speed recording is also possible. Furthermore, even if the wavelength of the optical pickup, the laser light, the type of the optical information recording medium, or the like changes, it can be immediately dealt with, and high recording / reproducing characteristics can always be maintained.

According to the second aspect, the correction time width selecting means is based on each time width detected from the reproduction signal from the pit portion and the non-pit portion formed on the optical information recording medium for information recording. An increase / decrease value of the time width of the signal level of the reference digital signal is obtained, and the increase / decrease value is used by the recording signal refining means for the first reference digital signal.
And a recording signal in which the time width of the second signal level is corrected is generated, and a pit is formed by irradiating the optical information recording medium with laser light by the recording signal. Can reduce the effect of thermal interference of
It is possible to form a pit having a pit portion and a non-pit portion having a length corresponding to the time width of the reference digital signal. As a result, the recording / reproducing characteristics can be improved, and the intensity of the laser light at the time of recording can be set low, so that double speed recording is also possible. Furthermore, even if the wavelength of the optical pickup, the laser light, the optical information recording medium, or the like changes, it is possible to immediately cope with this, and it is possible to maintain a high recording / reproducing characteristic at all times, which is a very excellent effect. It plays.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an optical information recording device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between a reference digital signal and pits in a conventional example.

FIG. 3 is a configuration diagram showing details of a recording signal generation circuit in one embodiment of the present invention.

FIG. 4 is a configuration diagram of a delay circuit according to an embodiment.

FIG. 5 is a timing chart of a delay circuit according to an embodiment.
To

FIG. 6 is a timing chart when selecting a correction value in one embodiment.

FIG. 7 is a timing chart when selecting a correction value in one embodiment.

FIG. 8 is a timing chart for recording information in one embodiment.

FIG. 9 is a timing chart for recording information in one embodiment.

FIG. 10 is a control flowchart in one embodiment.

FIG. 11 is a control flowchart in one embodiment.

FIG. 12 is a control flowchart in one embodiment.

FIG. 13 is a control flowchart in one embodiment.

FIG. 14 is a diagram showing a setting data table in one embodiment.

FIG. 15 is a diagram showing a control voltage selection table in one embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Optical disc, 2 ... Signal conversion part, 21 ... Optical pickup, 22 ... RF amplifier, 23 ... AC coupling, 24
… Inverter, 25… Analog switch, 26… Comparison
3 ... time width detector, 31 ... flip-flop, 32
... NOT circuit, 33 ... Counter, 34, 35 ... Latch circuit, 36, 37 ... Comparison circuit, 38 ... AND circuit, 5 ... Main control section, 6 ... Display section, 7 ... Switch section, 8 ... Recording section, 8
1 ... EFM encoder, 82 ... Recording signal generating circuit, 83
... laser drive control circuit, 84 ... laser diode, 100
... Rear end pulse generation circuit, 201-208 ... Delay circuit, 300 ...
Voltage control circuit, 400 ... Signal synthesis circuit.

Claims (2)

[Claims] 1. A first signal level corresponding to information to be recorded and representing a period for irradiating laser light having an intensity capable of forming a pit portion and laser light having an intensity lower than the first signal level are emitted. And a second signal level that represents a laser light irradiation stop period, and the first and second signal levels are time widths that form an arithmetic series that is an integral multiple of a predetermined reference time width. In the optical information recording method of forming pits by irradiating the optical information recording medium with laser light of a predetermined intensity based on the reference digital signal having After the information is recorded in a test area of the optical information recording medium on a trial basis, the step of reproducing the information is repeated a plurality of times to obtain the proper light intensity of the laser, and -Pilot formed experimentally using the light Detecting the intensity of reflected light from the bets, the information recorded on said optical information recording medium and reproducing a digital signal based on the reflected light intensity, further, a high level of the reproduction digital signals or B -
The time width of the level is detected, and from the time width,
After extracting a time width included in a predetermined allowable range centered on a comparison target time width that is a predetermined multiple of the reference time width, comparing the time width and the comparison target time width, and based on the comparison result. , Increase / decrease value of the time width of the signal level of the reference digital signal having at least the high level or low level of the reproduced digital signal and having the comparison time width, and the increase / decrease value at the time of official recording of information A recording signal in which the time width of the signal level of the reference digital signal is corrected by using the laser beam, and the optical information recording medium is irradiated with laser light by the recording signal to form a pit. Optical information recording method. 2. A first signal level corresponding to information to be recorded and representing a period for irradiating laser light having an intensity capable of forming a pit portion, and laser light having an intensity lower than the first signal level is emitted. And a second signal level representing a laser light irradiation stop period, the first and second signal levels being a reference digital signal having a time width that is an integral multiple of a predetermined reference time width. Based on this, in the optical information recording apparatus for forming a pit by irradiating the optical information recording medium with laser light of a predetermined intensity, a light intensity detecting means for detecting the intensity of the reflected light from the optical information recording medium, A signal reproducing means for reproducing the information recorded on the optical information recording medium as a digital signal based on the detection result of the light intensity detecting means, and a high level or a low level of the digital signal reproduced by the signal reproducing means. of A time width detection unit that detects a time width, and a time included in a predetermined allowable range centered on a comparison time width that is a predetermined multiple of the reference time width from among the time widths detected by the time width detection unit. Based on the comparison result of the time width extraction means, the time width extraction means, the time width extracted by the time width extraction means and the comparison time width, and the time width comparison means, Correction time width selection means for obtaining an increase or decrease value of the time width of the signal level of the reference digital signal having the comparison target time width and corresponding to the high level or low level of the reproduced digital signal, and the correction time width selection Recording signal generating means for generating a recording signal in which the time width of each signal level in the reference digital signal is corrected by using the increase / decrease value selected by the means; Zui, the Le - Le controls the driving of The - provided and The drive control means, an optical information recording apparatus characterized by.