CN100423092C - Optical disc device with adjustable recording speed and laser power - Google Patents

Abstract

A method of determining the power of a writing beam for recording a signal on an optical disc, comprising: performing test recording by recording a signal on a predetermined test area of the optical disc before actual recording; reproducing the signal from the predetermined test area of the optical disc; The signal produces a first recording characteristic, wherein said first characteristic represents the characteristic of a beta value as a function of the writing beam power, the beta value being obtained from the amplitude of the reproduced signal; a second recording characteristic is obtained from the first recording characteristic, wherein The second recording characteristic represents the characteristic of Δβ as a function of the power of the writing beam, and Δβ represents the change in the value of β in the first characteristic per unit power amount of the writing beam; using the preferred range of Δβ according to the obtained second The recording characteristic determines the recording power range, and the preferred range of Δβ is predetermined for realizing preferred recording, thereby determining the power of the writing beam within the recording power range; and determining the writing beam according to the first recording characteristic and within the recording power range the preferred power.

Description

Optical disc device with adjustable recording speed and laser power

technical field

The present invention relates to an optical disc recording speed measuring method for measuring the speed at which information can be satisfactorily recorded on an optical disc such as a compact disc recordable (CD-R) and a rewritable disc (CD-RW).

The present invention also relates to a method for measuring optical disc write laser power, for measuring the write laser power that can satisfactorily record information in optical discs such as compact disc recordable (CD-R) and rewritable disc (CD-RW) value.

Background technique

As a conventional recording method for optical discs such as CD-R and Digital Versatile Recordable Disc (DVD-R), multiple linear speeds (e.g., double speed, quadruple speed, ... etc.) for high-speed recording.

By changing the so-called countermeasures for adjusting the writing laser power, light irradiation time, light irradiation start time, etc. in accordance with the increase of the recording speed, it is possible to record while ignoring the recording errors of the respective recording speeds. However, some types of recording optical discs do not satisfy high-speed recording requirements, so recording errors are highly likely to occur when recording is performed at high speeds for these optical discs. Also, even if recording on an optical disc that satisfies high-speed recording is possible, recording errors may occur due to the compatibility between the recording device and the optical disc. When such a recording error occurs, the data area cannot be correctly reproduced.

The optical power control (OPC: adjusting the optimum writing power of the laser beam) for the implementation includes: performing test recording at a predetermined area of the optical disc at a plurality of recording speeds before normal recording; Recorded write laser power. However, in the case of OPC, it is not possible to determine a preferred speed range in which recording can actually be performed. If the optimum recording speed range can be determined corresponding to the type of disc to be recorded and the combination of the device for recording on the disc, the recording error can be suppressed by using the combination of the corresponding disc and the recording device, so that recording can be performed in a shorter time . However, an efficient method for determining the range in which a satisfactory recording speed can be obtained has not been proposed so far.

As an optimal method for amplifying and controlling the writing laser power according to the recording speed, an OPC method for performing optimal power control has been proposed, which includes: performing multiple writing laser power values in a predetermined area of the optical disc before normal recording. test recording; and obtaining a writing laser power value from a reproduction result of the test recording area.

In conventional OPC, the β value characteristic of the writing laser power value indicating the relationship between the writing laser power value and the β value is obtained from the signal reproduced from the test recording area, and the writing laser corresponding to the predetermined optimum β value is used The power value is used as the best writing laser power value. In addition, the β value is a parameter related to the level or amplitude of the reproduced signal, which can be obtained using the (a+b)/(a-b) relationship, where the letter a represents the peak level of the 8-14 modulation (EFM) signal waveform ( With "+" sign), as the return light receiving signal of the photodetector, and b (with "-" sign) indicates the bottom level of the return signal.

Furthermore, in conventional OPC, a writing laser power value corresponding to a predetermined optimum β value is determined. That is, the writing laser power value is measured considering only the β value. However, when the characteristics of optical discs differ with their types, recording with a simply determined writing laser power value in consideration of only the β value will deteriorate the quality level of the recorded state. For example, the relationship between the writing laser power value and the β value is usually linear, but sometimes it is a nonlinear relationship, as shown in Figure 49, which is due to factors such as disc fluctuations and dye inhomogeneity. As shown in Fig. 29, in the optical disc, the relationship between the β value and the writing laser power value basically has a linear characteristic, except for some BTs (in the example, when the β value is around 10, and the writing laser power The value is around 16mw). When recording is performed on an optical disc having such a characteristic with a writing laser power value (for example, 16 mW) corresponding to the β value effective point BT where the β value effectively changes, a satisfactory recording state quality cannot sometimes be obtained.

Contents of the invention

SUMMARY OF THE INVENTION The present invention takes the above circumstances into consideration, so a first object of the invention is to provide a method for measuring a recording speed of an optical disk which can measure a recording speed at which a satisfactory recording can be obtained with a small recording error. A second object of the present invention is to provide a method for measuring optical disc writing laser power for obtaining a writing laser power value capable of reducing recording errors regardless of the type of recording optical disc.

In order to achieve the first object, according to the present invention, there is provided a method of determining the power of a write beam for recording a signal on an optical disc, comprising: a recording step by recording a signal on a predetermined test area of the optical disc before actual recording. Carry out test recording; Reproduce step, reproduce signal from the predetermined test area of optical disc; Produce the first recording characteristic according to reproduced signal, wherein said first characteristic represents the characteristic of the β value as the function of writing beam power, and β value is according to the reproduction The amplitude of the signal is obtained; the second recording characteristic is obtained from the first recording characteristic, wherein the second recording characteristic represents the characteristic of Δβ as a function of the power of the writing beam, and Δβ represents the first of the power amount of the unit writing beam A change in the value of β in the characteristic; a determining step of determining a recording power range based on the obtained second recording characteristic using a preferred range of Δβ which is predetermined for realizing preferred recording, thereby determining the writing power range within the recording power range the power of the input beam; and determine the preferred power of the writing beam according to the first recording characteristic and within the recording power range.

The above method also includes: generating a third recording characteristic according to the reproduced signal, the third recording characteristic representing the relationship between the power of the writing beam and at least one of a plurality of qualitative parameters related to the characteristic of the recording, and from the detection comprising The frequency of the frame synchronization signal in the reproduced signal of the optical disc, the C1 error contained in the reproduced signal, the jitter of the reproduced signal, the deviation of the reproduced signal, the degree of modulation of the reproduced signal, the reflectivity of the laser beam from the disc, and the Selected from the parameter group composed of amplitude; wherein the determining step includes determining the recording power range according to the generated third recording characteristic in addition to the obtained second recording characteristic.

In the above method, said recording step includes reproducing a signal at a read rate lower than the signal write rate during test recording; the reproducing step includes reproducing a plurality of signals by performing a plurality of reproducing times on the test area; The determining step includes determining a recording power range divided into an upper side and a lower side, and the determining step further includes determining a preferred power of the writing beam within the determined lower side of the recording power range.

According to the present invention, there is also provided an apparatus for recording a signal on an optical disc using a writing beam having a preferred power, the apparatus comprising: a test recording section which performs signal recording on a predetermined test area of the optical disc before actual recording. a test recording of the optical disc; a reproducing part that reproduces a signal from a predetermined test area of the optical disc; a generating part that generates a first recording characteristic according to the reproducing signal, and the first recording characteristic represents the value of β as a function of the power of the writing beam characteristic, the β value is obtained according to the amplitude of the reproduced signal; the generating section further generates a second recording characteristic from the first recording characteristic, wherein the second recording characteristic represents the characteristic of Δβ as a function of the writing beam power, and Δβ represents a change in the value of β in the first characteristic of the unit power amount of the writing beam; and a determination section that determines the recording power range from the second recording characteristic using a preferred range of Δβ, the preferred range of Δβ being Predetermined for achieving preferred recording so that the power of the writing laser beam is determined within the recording power range; and the preferred power of the writing beam is determined within the recording power range in accordance with the first recording characteristic.

According to another aspect of the present invention, there is provided an apparatus for recording a signal on an optical disc using a writing light beam having a preferred power, the apparatus comprising: a test recording section which is placed in a predetermined test area of the optical disc before actual recording The test recording of the signal is performed on the optical disk; the reproducing part reproduces the signal from a predetermined test area of the optical disc; the generating part generates the first recording characteristic according to the reproducing signal, and the first recording characteristic represents the characteristic of the β value as a function of the power of the writing beam , the β value is obtained from the amplitude of the reproduced signal; the generating section generates a second recording characteristic from the first recording characteristic, the second recording characteristic represents the characteristic of Δβ as a function of the writing beam power, and Δβ represents the unit a change in the β value in the first characteristic of the power amount of the writing beam; the generating section generates a third recording characteristic representing the power of the writing beam and a plurality of characteristics related to recording according to the reproduced signal The relationship between at least one of the qualitative parameters, and from the detection of the frequency of the frame synchronization signal contained in the reproduced signal of the optical disc, the C1 error contained in the reproduced signal, the jitter of the reproduced signal, the deviation of the reproduced signal, the addition to the modulation degree of the laser beam, the reflectivity of the laser beam from the optical disc, and the amplitude of the reproduced signal selected from the parameter group; and a determination section that uses a preferred range of Δβ based on the second recording characteristic and the third recording The characteristic determines the recording power range, and the preferred range of Δβ is predetermined for realizing preferred recording, so that the power of the writing beam is determined within the recording power range and according to the first recording characteristic, the second power characteristic and the third power characteristic and in The preferred power of the writing beam is determined within the recording power range.

According to still another aspect of the present invention, there is provided a method of measuring recording speed by writing a laser beam into an optical disc. The steps adopted by the method of the present invention are to perform a test recording of a signal on a predetermined recording area of the optical disc before actual recording at one or more recording speed levels, while reproducing the signal from the predetermined area of the optical disc by a readout laser beam, and generating a first characteristic recording speed from the reproduced signal, said first characteristic representing the relationship between an optical characteristic of the laser beam and a qualitative parameter of the recording state of the signal, said optical characteristic being obtained either by using a readout laser beam reflected from the optical disc The β value represents, or expressed by the writing laser beam, based on the predetermined preferred range of the qualitative parameter to generate the second characteristic from the first characteristic, and makes the second characteristic represent the recording speed and the predetermined preferred range of the qualitative parameter corresponding to the recording state A relation between the range of the relational characteristic of , and the preferred value of the recording speed is determined according to the second characteristic and the predetermined range of the optical characteristic intended to obtain the preferred recording state.

According to the present invention, parametric recording is carried out on an optical disc subjected to normal recording, and the β value or the writing laser power value is used to set qualitative parameters for the recording status level obtained by testing the recording speed. Thus, the recording speed obtained from the value of β or the value of the writing laser power is the preferred value that can be obtained. Therefore, the recording speed at which satisfactory recording is achieved with a small recording error can be determined.

In addition, the above-mentioned method further includes the following steps: storing preferred ranges of a plurality of qualitative parameters corresponding to various types of optical discs, detecting the type of the optical disc in the case of test recording, and making the step of generating the second characteristic use the The optical range of the qualitative parameter, and the step of determining a preferred range using optical characteristics corresponding to the type of detection of the disc.

Also, in said method, the step of generating the first characteristic adopts a frequency detected from a frame synchronization signal contained in a signal reproduced from an optical disc signal, an error C1 contained in the reproduced signal, a jitter of the reproduced signal signal, a deviation of the reproduced signal, a degree of modulation applied to the laser beam, the reflectivity of the laser beam from the disc, and the amplitude of the reproduced signal are selected qualitative parameters.

According to the present invention, there is provided a method of measuring the power of a write beam used to record a signal onto an optical disc. The method of the present invention is performed by the following steps. Test recording is performed, and a signal from a predetermined test area of the optical disc is reproduced, and a recording characteristic representing the relationship between Δβ and the power of the writing beam is produced in accordance with the reproduced signal. Where Δβ represents the deviation of the power amount β value per unit writing beam, and the Δβ value is obtained from the amplitude deviation of the reproduced signal, and the preferred range of Δβ is used to determine the preferred range of the writing beam according to the resulting recording characteristics. Said power is predetermined to achieve optimal recording.

According to the method of the present invention, the relationship between the writing laser power value and Δβ as the amount of change in the β value is obtained from the signal reproduced before test recording, and the writing laser power value is determined considering the Δβ value. Therefore, it is possible to measure the writing laser power value for satisfactory recording even with an optical disc having a characteristic of the so-called β effective point where individual irregular products such as warp and dye irregularity are measured. For a homogeneous disc, the value of β effectively varies with respect to the value of the writing laser power.

In addition, according to the present invention, there is also provided a method of measuring the power of a write beam for recording a signal on an optical disc. The execution step of the method of the present invention is, before actual recording, carry out the testing method of the power of the writing light beam of test recording on the signal on the predetermined test area of optical disc, reproduce signal from the predetermined test area of optical disc, generate recording according to the reproduced signal characteristic, expressing the relationship between the power of the writing beam and at least one of the qualitative parameters of the recording characteristics related to the recording volume, and derived from the frequency of the frame synchronization signal contained in the reproduction signal of the optical disc, contained in the reproduction signal C1 error, a jitter of a reproduced signal, a deviation of a reproduced signal, a degree of modulation added to a laser beam, a laser beam is selected from the group consisting of the reflectivity of an optical disc and the amplitude of a reproduced signal, etc., and is measured according to the The preferred power of the write beam used in the actual recording is the resulting recording characteristic.

According to the present invention, there is no relationship between the writing laser power value and the β value, but the relationship between the writing laser power value and at least one parameter related to the recording quality level, such as the detection frequency of the frame synchronization signal, the C1 error, from the test The resulting deviation of the reproduced signal in the recording area and the laser power value are determined in consideration of the relationship described above. Therefore, it is possible to determine the writing laser power value for satisfactory recording, even if the optical disc has a so-called β effective point characteristic, at which point the β value corresponds to the write The input laser power value will have an effective change.

Also, according to the present invention, there is provided a method of measuring the power of a write beam for recording a signal on an optical disc. The method of the present invention comprises the steps of performing test recording on a signal on a predetermined test area of the optical disc before actual recording, reproducing the signal from the predetermined test area of the optical disc, and generating a recording characteristic according to the reproduced signal, representing the writing beam The power and recording characteristics and the β value obtained from the amplitude deviation of the reproduced signal, the detection of the frequency of the frame synchronization signal included in the reproduced signal of the optical disc, the C1 error contained in the reproduced signal, the jitter of the reproduced signal, A deviation of the reproduced signal, a degree of modulation applied to the disc, a step in the relationship between a qualitative test selected from the group consisting of the reflectivity of the laser beam of the disc and the amplitude of the reproduced signal, and other recordings are produced according to the reproduced signal Characterization, showing the relationship between the power of the writing beam and other qualitative tests, and determining the preferred power of the writing beam for actual recording according to the recording parameters generated.

According to the method of the present invention, the relationship between the laser power value and at least two or more relevant recording quality parameters, such as the beta value, the detection frequency of the frame synchronization signal, the C1 error, the jitter, and the recording area from the test The reproduced signal is deviated, and the write laser power value is determined by considering a number of parameters related to the recording level. Therefore, it is possible to determine the writing laser power value for satisfactory recording even if the optical disc has the characteristics of the so-called important point of β, at which some parameters such as the β value are due to various products such as the fluctuation of the optical disc and the unevenness of the dye. , there will be effective changes relative to the writing laser power value.

Description of drawings

FIG. 1 is a block diagram showing the structure of an optical disc recording/reproducing apparatus according to a first embodiment of the present invention.

Fig. 2 shows a schematic diagram of a test area in which test recording is performed in an optical disc by means of an optical disc recording/reproducing apparatus.

FIG. 3 is a block diagram showing the structure of function keys of a controller which is a structural element of the optical disk recording/reproducing apparatus.

FIG. 4 is an explanatory diagram showing a method of deriving the maximum speed recorded by the controller.

FIG. 5 is an explanatory view showing storage contents of a C1 error preference value memory which is a structural element of the controller.

FIG. 6 is an explanatory diagram showing a method of deriving the maximum speed recorded by the controller.

FIG. 7 is an explanatory view showing storage contents of a β preferred value memory which is a structural element of the controller.

Fig. 8 is an explanatory diagram showing switching timing between CAV operation and CLV operation of the optical disk recording/reproducing apparatus.

Fig. 9 is a flowchart showing a control process executed by the controller when the optical disk recording/reproducing apparatus records data.

Fig. 10 is an explanatory diagram showing a method of deriving the recording minimum speed by the controller according to a modified example of the optical disk recording/reproducing apparatus.

FIG. 11 is an explanatory diagram showing a method of deriving the recording minimum speed by the controller according to a modified example of the optical disc recording/reproducing apparatus.

Fig. 12 is an explanatory diagram showing switching timing between CAV and CLV operations in a modified embodiment of the optical disc/reproducing apparatus.

13A and 13B are explanatory diagrams showing other derivation methods of recording the maximum speed by the controller.

Fig. 14 is an explanatory diagram showing another derivation method of recording the maximum speed by the controller.

Fig. 15 is a block diagram showing the configuration of another modified example of the optical disk recording/reproducing apparatus.

Fig. 16 is an explanatory diagram showing a method of deriving the recording maximum speed by the controller according to another modified example of the optical disk recording/reproducing apparatus.

Fig. 17 is a block diagram showing the configuration of another modified example of the optical disc recording/reproducing apparatus.

Fig. 18 is an explanatory diagram showing a method of deriving the recording maximum speed by the controller according to another modified example of the optical disc recording/reproducing apparatus.

Fig. 19 is a block diagram showing the configuration of another modified example of the optical disk recording/reproducing apparatus.

Fig. 20 is an explanatory view showing a method of deriving the recording maximum speed by the controller according to another modified example of the optical disk recording/reproducing apparatus.

21A-21C are graphs showing the relationship between parameters relating to the recording level and the value of β which can be used to derive the recording speed by the optical disc/reproducing apparatus.

Fig. 22 is a block diagram showing a functional structure of a controller as a structural element of the second embodiment of the optical disc recording/reproducing apparatus.

FIG. 23 is an explanatory view showing storage contents of a β preferred value information storage which is a structural element of the controller.

Fig. 24 is a diagram showing an example of the β value and C1 error for each laser power value obtained by test recording by the optical disc recording/reproducing apparatus.

Fig. 25 is an explanatory view showing the process of determining the optimum writing laser power value from the relationship between the writing laser power value and the β value.

FIG. 26 is an explanatory diagram showing the storage contents of the C1 error preference value information memory which is a structural element of the controller.

FIG. 27 is an explanatory diagram showing a process of determining an optimum writing laser power value from the relationship between the writing laser power value and the C1 error value.

Fig. 28 is a flowchart showing a process executed by the controller at the time of recording in another optical disc recording/reproducing apparatus.

FIG. 29 is an explanatory diagram showing a procedure for determining an optimum write laser power value from a write laser power value and a frame synchronization signal detection frequency in a modified example of an optical disc recording/reproducing apparatus.

Fig. 30 is an explanatory view showing the process of determining the optimum write laser power value from the relationship between the write laser power value and the jitter value in another modified example of the optical disc recording/reproducing apparatus.

Fig. 31 is an explanatory view showing the process of determining the optimum write laser power value from the relationship between the write laser power value and the deviation value in another modified example of the optical disc recording/reproducing apparatus.

Fig. 32 is an explanatory diagram showing the process of determining the optimum write laser power value from the relationship between the write laser power value and the amplitude value of the RF signal in another modified example of the optical disc recording/reproducing apparatus.

Fig. 33 is an explanatory view showing the procedure of determining the optimum write laser power value from the relationship between the write laser power value and the degree of modulation in another modified example of the optical disc recording/reproducing apparatus.

Fig. 34 is an explanatory view showing the process of determining the optimum writing laser power value from the relationship between the writing laser power value and the reflectance in another modified example of the optical disc recording/reproducing apparatus.

Fig. 35 is an explanatory diagram showing a procedure for determining an optimum writing laser power value in another modified example of the optical disc recording/reproducing apparatus.

Fig. 36 is a block diagram showing the procedure of the optical disc recording/reproducing apparatus according to the third embodiment of the present invention.

Fig. 37 is a block diagram showing a functional structure of a controller as a structural element of the optical disc recording/reproducing apparatus of the third embodiment.

Fig. 38 is an explanatory view showing the process of determining the optimum write laser power value from the relationship between the write laser power value and the C1 error value in the optical disc recording/reproducing apparatus according to the third embodiment.

Fig. 39 is an explanatory view showing the process of determining the optimum write laser power value in relation to the write laser power value and the frame synchronization signal detection frequency in the optical disc recording/reproducing apparatus according to the third embodiment.

Fig. 40 is an explanatory view showing the process of determining the optimum write laser power value in relation to the write laser power value and the frame synchronization signal detection frequency value in the optical disk recording/reproducing apparatus according to the third embodiment.

Fig. 41 is an explanatory view showing the process of determining the optimum write laser power value from the relationship between the write laser power value and the C1 error value in the modified example of the optical disc recording/reproducing apparatus according to the third embodiment.

Fig. 42 is an explanatory view showing the process of determining the optimum write laser power value from the relationship between the write laser power value and the C1 error value in the modified example of the optical disk recording/reproducing apparatus according to the third embodiment.

43 is an explanatory diagram showing a modified example of the process of determining the optimum writing laser power value based on the relationship between the writing laser power value and the frame synchronization signal detection frequency in the modified example of the optical disc recording/reproducing apparatus according to the third embodiment.

44 is an explanatory diagram showing another modification of the process of determining the optimum writing laser power value in relation to the relationship between the writing laser power value and the frequency of the frame sync detection signal in the modified example of the optical disc recording/reproducing apparatus according to the third embodiment.

Fig. 45 is a block diagram showing a functional structure of a controller as a structural element of an optical disk recording/reproducing apparatus according to a fourth embodiment of the present invention.

Fig. 46 is a graph showing an example of the relationship between the write laser power value and the β value obtained by test recording by the optical disc recording/reproducing apparatus according to the fourth embodiment.

Fig. 47 is an explanatory view showing the process of determining the optimum write laser power value from the relationship between the write laser power value and the Δβ value in the optical disc recording/reproducing apparatus according to the fourth embodiment.

Fig. 48 is an explanatory view showing the process of determining the optimum writing laser power value in a modified example of the optical disc recording/reproducing apparatus according to the fourth embodiment.

Fig. 49 is an explanatory diagram showing the relationship between the writing laser power value and the β value obtained from the reproduced signal of the test area on the optical disc for test recording.

Detailed ways

Embodiments of the present invention will be described below with reference to the drawings.

A-1. Structure of the first embodiment

First, FIG. 1 shows a schematic block diagram of the structure of an optical disc recording/reproducing apparatus according to a first embodiment of the present invention. As shown in Figure 1, the optical disc recording/reproducing apparatus comprises a light receiver 10, a spindle motor 11, an RF amplifier 12, a servo circuit 13, an address detection circuit 14, a decoder 15, a controller 16, an encoder 17, a countermeasure circuit 18, Laser driver 19 , laser power control circuit 20 , frequency generator 21 , envelope detection circuit 22 , C1 error detection circuit 23 and β detection circuit 24 . The spindle motor 11 is a motor that rotates/drives an optical disk (eg, CD-R) D for recording data. The photoreceiver 10 has a laser diode, an optical system such as lenses and mirrors, and a return light receiving element. The optical receiver irradiates the optical disc D with a laser beam at the time of recording and reproducing, and receives returning light from the optical disc D, and outputs an RF signal subjected to 8-14 modulation (EFM) to the RF amplifier 12 as an optical reception signal. In addition, the optical receiver 10 has a monitor diode, and the light returned from the optical disc D generates a current in the diode, and the current is supplied to the laser power control circuit 20 .

The RF amplifier 12 amplifies the signal supplied from the optical receiver 10 and subjected to EFM modulation, and outputs the amplified RF signal to the servo circuit 13, the address detection circuit 14, the envelope detection circuit 22, the β detection circuit 24 and the decoder 15. Decoder 15 EFM-modulation is supplied with an EFM-modulated RF signal from RF amplifier 12 and generates reproduced data upon reproduction.

On the other hand, when recording, the decoder 15 EFM-modulates the RF signal provided from the RF amplifier 12 when the decoder 15 reproduces the test recording area, and the C1 error detection circuit 23 detects the C1 error according to the demodulated signal, and outputs the error to the controller. The C1 error detection circuit 23 subjects the EFM demodulated signal to error correction using an error correction code called Interleaved Solomon Code (CIRC), and detects the first error that cannot be performed within one subcode frame (98 EFM frames). The number of frames corrected, i.e., the frequency of C1 errors.

When recording, the process of the optical disc recording/reproducing device of the present invention is, before normal recording, a predetermined area (see FIG. 2 ) on the inner circumference side of the optical disc D is subjected to test recording, and a recording speed is obtained. This speed allows satisfactory recording with respect to the reproduction result based on the test recording area. The C1 error detection circuit 23 detects the C1 error of the reproduced signal in the test recording area, and outputs the error to the controller 16 .

here. Referring to FIG. 2, a test area for test recording of an optical disc D (CD-R) is explained. An area based on the optical disc D having a diameter of 46-50 mm is used as the lead-in area 114, and a program area 118 for recording data and a remaining area 120 are located on the outer peripheral side of the lead-in area. On the other hand, there is also an inner peripheral side power calibration area (PCA) 112 . The PCA area 112 on the inner peripheral side includes a testing area 112a and a counting area 112b. The test area 112a is subjected to test recording prior to the normal recording process. Here, an area where a large amount of test recording can be performed is made a test area 112a, and an EFM signal indicating the test area 112a whose recording is partially ended at the end of the test recording is recorded in the count area 112b. Therefore, when the optical disc D is subjected to test recording, the EFM signal of the count area 112b is read. Then, the location of the test area 112a where the test recording is to be performed can be obtained. In the optical disk recording/reproducing apparatus of the present invention, the test area 112 is subjected to test recording before normal recording.

Referring again to FIG. 1, the address detection circuit 14 extracts a wobble signal component from the EFM signal provided by the RF amplifier 12, and, for time information indicating each position contained in the wobble signal component, recognizes disc and disc type information such as The disc dye information is decoded and the information is output to the controller 16 .

The β detection circuit 24 calculates a β (symmetry) value as a parameter related to the reproduction signal level of the EFM modulated RF signal supplied from the RF amplifier 12 at the time of reproduction of the test recording area, and outputs the calculation result to the controller 16 . The β value is determined by (a+b)/(a-b), where the letter b represents the peak (symbol +) of the signal waveform subjected to EFM modulation, and the letter b represents the bottom level (symbol -) of the signal waveform.

The envelope detection circuit 22 detects the envelope of the EFM signal of the counting area 112b of the optical disc D, so as to detect a part of the predetermined test area of the optical disc D, from which the parameter recording is partially started before the parameter is performed.

The servo circuit 13 performs rotation control of the spindle motor 11 , as well as focus control, tracking control, and feedback control of the optical receiver 10 . In the optical disc recording/reproducing apparatus of the present invention, a constant angular velocity (CAV) method of driving the optical disc D at a constant angular velocity at the time of recording and a method of driving the optical disc D while the linear velocity is set to be constant can be switched and executed. A constant linear velocity method. The servo circuit 13 changes the CAV control and the CLV control in response to a control signal from the controller 16 . In the CAV control performed by the servo circuit 13, the rotation speed of the spindle motor 11 detected by the frequency generator 21 is controlled to match the set rotation speed. In addition, in the CLV control by the servo circuit 13, the spindle motor 11 is controlled so that the swing signal of the EFM-modulated signal supplied from the RF amplifier 12 indicates a set linear velocity amplified.

The encoder 17 EFM-modulates the supplied recording data, and outputs the data to the countermeasure circuit 18 . The countermeasure circuit 18 executes time-axis correction processing with respect to the EFM signal supplied from the encoder 17 , and outputs a drive signal to the laser driver 19 . The laser driver 19 drives the laser diode of the optical receiver 10 in accordance with the signal modulated by the recording data supplied from the countermeasure circuit 18 and controls the laser power control circuit 20 .

The laser power control circuit 20 controls the laser power emitted by the laser diode of the optical receiver 10 . Specifically, the laser power control circuit 20 controls the laser driver 19 according to the current value provided by the monitoring diode of the optical receiver 10 and the information indicating the optimal target value of the laser power provided by the controller 16, so as to have the optimal laser power. A laser beam of high power is emitted from the light receiver 10 .

The controller 16 is composed of a central processing unit (CPU), a read-only memory (ROM), a random access memory (RAM), etc., and controls the operation of each device component of the optical disc recording/reproducing device according to a program stored in the ROM.

First, the controller 16 controls the components of each device to perform test recording on a predetermined area of the optical disc D set in the optical disc recording/reproducing device before the above-mentioned normal or actual recording. In addition, the controller 16 executes recording speed measuring processing for obtaining a recording speed in which satisfactory recording without any recording error can be performed on the optical disc D subjected to test recording using the optical disc recording/reproducing apparatus, based on The signal obtained when the test recording area is reproduced from the β value detected by the β detection circuit 24, and the count value of the C1 error detected by the C1 error detection circuit 23 are used to measure the recording speed. FIG. 3 shows the functional configuration of the controller 16 that executes recording speed measurement processing to obtain the recording speed.

As shown in FIG. 3, the controller 16 has a C1 error preferred value storage 200, a recording speed-β characteristic function storage 201, a β preferred value storage 202, a β-C1 error characteristic generation part 203, and a recording speed-β characteristic function generation section 203. part 204 and recording speed generation part 205.

In the β-C1 error characteristic generating section 203, the β value detected by the β detection circuit 24 and the count value of the C1 error detected by the C1 error detection current 23 (hereinafter referred to as C1 error value) are provided. Afterwards, in FIG. 4A representing a plurality of recording speeds (for example, V1, V2, V3; V1<V2<V3) the relationship between the β value and the count value of the C1 error indication of the recording characteristics can be obtained from the provided The β value and C1 error value are obtained. In order to obtain the characteristics of each of a plurality of recording speeds, test recording is performed with three recording speeds V1, V2, V3, and from the β value and C1 error value detected from the reproduced signal in the area recorded at each speed can be obtained for each Velocity recording characteristics. Furthermore, instead of performing test recording at each speed and obtaining the recording characteristics shown in FIG. 3, such as the method shown in FIG. 3, the method includes: performing test recording at only one recording speed; As a result of experiments performed beforehand, the velocity was obtained from the reproduced signal of the test recording area; on the basis of obtaining the characteristics of the recording speed different from the test recording speed. Also, for a certain speed (one or more speeds), one or more test records can be carried out, but it is better to carry out multiple test records to make the obtained judgment results more accurate.

The recording speed-β characteristic generation section 204 obtains a recording speed characteristic based on the β-C1 error characteristic for each recording speed obtained by the β-C1 error characteristic generation section 203 as described above and stored in the C1 error preference. The relationship between the C1 error value information stored in the value memory 200 and the recording speed is as shown in FIG. 4 .

As shown in FIG. 5, in the C1 error preference value storage 200, information indicating a range of C1 error values for performing satisfactory recording is stored for each type of optical disc D (different manufacturer and dye). In the example described, information is stored indicating that satisfactory recording can be performed with an A-type disc within a C1 error value of 0-10 (98 C1 error value at a maximum). Here, the information stored in the C1 error preference memory 200 is a value obtained by previous experiments for each type of optical disc. The recording speed-β characteristic generating section 204 obtains the recording speed-β characteristic shown in FIG. 4B by the following method using the C1 error preference value information stored in the C1 error preference value memory 200 .

First, the recording speed-β characteristic generation section 204 obtains C1 error preference information corresponding to the information type of the optical disc D detected by the address detector circuit 14 from the preference information stored in the C1 error preference storage 200 . In addition, based on the obtained C1 error preference value information and the β-C1 error characteristic obtained by the β-C1 error characteristic generation section 203 shown in FIG. An upper and lower bound for the obtained beta value within the range indicated by the C1 error preference information. For example, when the type information of the optical disc detected by the address circuit 14 is A, preference information (0-10) corresponding to type A is obtained from the C1 error preference information stored in the C1 error preference storage 200 . In addition, as shown in FIG. 4B , it is possible to obtain the possible upper limit values PJ1, PJ2, PJ3 and lower limit values PK1, PK2, PK3.

When obtaining the possible upper limit values PJ1, PJ2, PJ3 and lower limit values PK1, PK2, PK3 of the β values of the respective recording speeds, the recording speed-β characteristic generation section 204 obtains the recording speed and the basis value as shown in FIG. 4B. The obtained upper limit values PJ1, PJ2, PJ3 and lower limit values PK1, PK2, PK3, and the possible upper and lower limit value ranges of the β value of the function information stored in the recording speed-β characteristic function memory 201 Relationship. In the recording speed-beta value characteristic function storage 201, function information indicating changes in upper and lower limit values of the beta value for setting the C1 error value within a preferred range corresponding to a change in the recording speed is stored. Here, function information is obtained based on the upper and lower limit values of the β value for a large number of recording speeds obtained in advance from test recording experiments performed at a large number of recording speeds, and the linear function is stored in this embodiment (i.e., as The function shown by the curve in Figure 4B changes linearly). As for the function information, optimal information is stored in advance for each type of optical disk D (different manufacturers and dyes), and appropriate function information can be selected according to the type information of the optical disk D. Whereas, the displacement of the upper and lower limits of the β-value with respect to the recording speed can be defined from the function information and the upper limit values PJ1, PJ2, PJ3 and the lower limit values PK1, PK2, PK3 using lines L1 and L2 shown in FIG. 4B. When limited by lines L1 and L2, the relationship between the value β _m and the recording speed indicated by the possible range of the β-value of the upper limit value of β and the lower limit value of β and the recording speed can be obtained, and can be obtained as shown in Fig. 6 Recording speed-beta range characteristics shown. In addition, three upper limit values PJ1, PJ2, PJ3 and lower limit values PK1, PK2, PK3 are obtained from the above-mentioned characteristics of the three recording speeds, and the possible range of _βm between the β value and the recording speed can be obtained by using these values Relationship. In two functions (ie, linear function Y=ax+b+c, where c represents the value that changes with the upper and lower limit values of the actual measurement, and a, b are fixed values), they are used to be stored in the record The upper and lower limit values in the speed-β characteristic function memory 201, when obtaining the upper limit value PJ1 and the lower limit value PK1 of a certain speed V1, the linear function can be used to define the lines L1 and L2. Thus, the relationship between the possible range β _m of the β value and the recording speed can be obtained. In this way the relationship between the possible range β _m and the recording speed can be obtained from the β-C1 error characteristic of a speed. In this case, of course, test recording can be done at a single speed. Also, instead of obtaining the upper and lower limit values as described above, a function indicating the relationship between the possible range β _m of the β value and the recording speed (that is, a linear function Y=AX+B=C, where C Indicates a value that varies with the difference between the actually measured upper limit value and the lower limit value of the speed specified therefor, and A, B are fixed values). The possible range of β values and the relationship between β _m and the recording speed can be obtained from actual measurements of the relationship between these functions and the relationship between the upper and lower limit values of the speed.

The recording speed generating section 205 obtains a maximum speed at which the optical disc recording/reproducing apparatus can be compared with respect to the recording speed-β range characteristic obtained by the above-mentioned recording speed-β characteristic generating section 204 and stored in the β value preferred value memory The recording of the β preference information in 202 is performed with the test-recorded optical disc D maintaining a satisfactory recording level. As shown in FIG. 7, in the β preferred value storage 202, a value indicating a fluctuation range that allows satisfactory recording for each type of optical disk D (different manufacturers and dyes) is stored. In the example described, information indicating that satisfactory recording can be performed with an A-type optical disk with β in the range of 10 or more is stored. That is, it is difficult for the optical disk recording/reproducing apparatus to control β within a small range of values when the target falls within the preferred β value range because of disc D distortion, dye unevenness, and the like. In the β preferred value storage 202, considering the difficulty of controlling with a very small target β value, it is sufficient to store the optical disc recording/reproducing device to control the β value within the target range even if the optical disc D has distortion, dye unevenness, etc. Appear. Here, the information stored in the beta preference storage 202 is a value previously obtained experimentally for each disc type. The recording speed generation section 205 uses the preferred value information stored in the β value range of the β preferred value memory 202 to obtain the maximum recording speed at which the speed β is located at the value indicated by the preferred value information from the characteristics shown in FIG. Within the range, the maximum recording speed is the maximum speed at which the optical disc recording/reproducing apparatus can perform recording on the optical disc D subjected to test recording with the recording level maintained. The example in FIG. 6 shows a case where the preferred value information of the range β _m of the β value is 10 or more. In this case, the maximum value of the recording speed at which the characteristic line L3 intersects the line L4 and β _m =10 was obtained as the maximum recording speed.

Returning to FIG. 1, the controller 16 in the optical disk recording/reproducing apparatus of the present invention controls hardware to perform switching between CAV and CLV based on the recording maximum speed obtained above. Specifically, the controller 16 controls the servo circuit 13 so as to utilize the CAV method when recording on the innermost peripheral side. After starting recording in this way, the controller 16 determines the radial position of the optical disk D based on the address information supplied from the address detection circuit, and drives the spindle motor 11 at a predetermined angular velocity. In this case, the controller outputs a control signal for switching the CAV method to the CLV method to the servo circuit 18 upon detecting the radial position corresponding to the maximum speed obtained as described above. As shown in FIG. 8, the spindle motor 11 is driven in the CAV method at the number of revolutions corresponding to the linear velocity of 12 times the velocity at the innermost peripheral position. The radial position is detected when the linear speed reaches the maximum speed (16 times the speed) of the number of revolutions. Then, the controller 16 outputs a control signal for switching CLV to the servo circuit 13 . After that, in the CLV method, the servo circuit 13 drives the spindle motor 11 at 16 times the speed.

Also, when recording in the CAV method, the controller 16 sequentially outputs information indicating the target value of the optimum laser power to the laser power control circuit 20 in accordance with the linear velocity. That is, when the CAV control is performed, as the recording linear velocity is successively changed, information indicating the optimum target value of the laser power for successively changing the linear velocity is output. Specifically, recording on the radial disc on the outer peripheral side. That is, as the linear speed increases, a large laser power as a target value is sequentially output to the laser power output circuit 20 . Here, the target value of the optimum laser power corresponding to the current linear velocity may be obtained with reference to a data sheet obtained by prior experiments, or may be obtained by a so-called OPC method. The OPC method includes: performing test recording of the optical disc D at the innermost peripheral portion before normal recording; and obtaining a target value of an optimum laser power at each linear velocity from a reproduced signal obtained by reading out the recorded portion.

A-2 Operation of the first embodiment

The structure of the optical disc recording/reproducing apparatus according to the first embodiment of the present invention has been described above. The recording operation by the optical disc recording/reproducing apparatus constructed as described above will be described below with reference to the flowchart performed by the controller 16 shown in FIG.

First, when the user sets the optical disc D in the optical disc recording/reproducing apparatus and instructs recording start, a recording test is performed on the test area 112a of the set optical disc D (step Sa1). Then, the controller 16 utilizes the β value detected from the reproduced signal of the test recording area and the C1 error value to drive the maximum recording speed at which the optical disk recording/reproducing apparatus performs satisfactory recording corresponding to the set optical disk D (step Sa2 ).

Thereafter, the controller 16 instructs the servo circuit 13 to drive the optical disc D by the CAV method (step Sa4), and performs recording by the CAV method. When the recording of the CAV method is started in this way, the controller 16 outputs to the laser power control circuit 20 information indicating the target value of the optimum laser power corresponding to the change in the linear velocity, so that the laser power is increased as the linear velocity increases. Increase. Thus, the laser power control circuit 20 feedback-controls the laser power so as to obtain the target value supplied from the controller 16 .

In addition, the controller 16 judges whether or not the linear velocity of the recording position of the optical disk D has reached the above-mentioned maximum recording velocity based on the address information detected from the address detection circuit (step Sa4). Here, when it is judged that the linear velocity at the recording position has not reached the maximum linear velocity, the controller 16 continuously performs recording in the CAV method. When all the data to be recorded are recorded, the recording process ends (step Sa5 judges "YES"). On the other hand, when the linear velocity of the recording position judged at the Sa4 step reaches the maximum recording speed, the controller outputs a control signal indicating that the recording method is switched from the CAV method to the CLV method to the servo circuit 13, and performs recording with the CLV method (Step Sa6 ).

Thereafter, when recording by the CLV method, the controller 16 judges whether or not the recording is finished (step Sa7). When all the data to be recorded are recorded, or when the user instructs the end of the recording, the judgment result is "YES", and the recording process ends.

In this embodiment, the test recording is performed before the normal data recording process, and the maximum recording speed for satisfactory recording on the optical disk D can be obtained from the reproduced signal of the test recording area. Also, when normal recording is performed, CAV recording is performed until the maximum recording speed is obtained. After the maximum recording speed is reached, CVA recording is performed at that speed. Therefore, data can be recorded in a short time without imparting a satisfactory recording quality level. Thus, when the user instructs recording without informing the corresponding recording speed of the optical disc D or that the optical disc D is compatible with the optical disc recording/reproducing apparatus, automatic data recording can be performed at a satisfactory recording level in a short time.

A-3 Improvement example

The present invention is not limited to the above-described embodiment, and various modifications can be made thereto as follows.

(improved example 1)

In the embodiments described above, CAV recording was not performed until the maximum recording speed consistent with the test recording results was reached. After the maximum speed recording is achieved, a CLV recording is performed. However, CLV recording can be performed at the maximum recording speed or a lower speed from the beginning.

In addition, the maximum recording speed obtained above is 12 times speed, but the user commands CLV recording at 16 times speed. In this case, the user is notified that satisfactory recording cannot be obtained at 16x speed CLV recording, and the user can be made to set the recording speed again. In addition, when the recording speed set by the user is higher than the maximum recording speed obtained above, the maximum recording speed or a lower recording speed can be automatically set without the user setting the speed again as described above. In this case, estimate the time required for recording at the changed/set recording speed and inform the user of the estimated time.

(Improved example 2)

In addition, in the above-mentioned embodiment, the maximum recording speed at which satisfactory recording can be obtained can be obtained, however, it is also necessary to consider the situation that the recording level is damaged when recording at a low speed (as shown in FIG. Values are subject to a range β _m reduction of β values within the preferred range). In this case, as shown in FIG. 11 , a certain speed value (10 or more in the illustrated example) indicated by the β preferred value information can be obtained as the minimum recording speed V _min .

As shown in Fig. 12, at the time of normal recording with the minimum recording speed obtained in this way, CLV recording is performed at a recording speed greater than the obtained minimum recording speed (4x speed in the example), and can be switched To CAV recording, the linear speed of CAV recording exceeds the minimum recording speed at this time.

(Improvement example 3)

In addition, in this embodiment, the recording speed is obtained based on the value of β, but it is not limited thereto, and the recording speed can also be obtained based on the writing laser power value. In this case, the controller 16 obtains the relationship between the lower writing laser power value and the C1 error value shown in FIG. 13A from each of a plurality of recording speeds of the C1 error value supplied from the C1 error detection circuit 23 . Here, as shown in FIG. 13A, when the writing laser power value is used as a reference instead of the β value, the recording power value also increases with a higher recording speed. Therefore, the recording speed as a reference is obtained according to the writing laser power value. Afterwards, each speed obtained by OPC and the characteristics of the optimum writing laser power values PL1, PL2, PL3 are used to obtain the upper limit values PJ1', PJ2', PJ3' and lower limit values PK1', PK2 of the power values ', the ratio of the difference between PK3' and the best writing laser power value, at this time, the C1 error value is not greater than the reference value for each speed from the best writing laser power value, that is, from the best writing The ratio (%) of the laser power value to the allowable power value. For example, the upper allowable range value PJ01(%) for the recording speed V1 can be obtained using the following equation.

PJ01=(PJ1'-PL1)/PL1*100

In this way, as shown in FIG. 13B, allowable upper limit range values PJ01, PJ02, PJ03 and allowable lower limit range values PK01, PK01, PK03 of the writing laser power at each recording speed can be obtained. In addition, as shown in FIG. 14, the relationship between the allowable range of the writing laser power value and the recording speed can be obtained, and the recording speed when the preferred range Pm of the writing laser power value indicates the predetermined value Pm1 can be obtained, and taken as the maximum recording speed.

(improved example 4)

Also, in this embodiment, the recording speed is obtained based on the range of β in which the C1 value is smaller than the predetermined value. However, the parameter related to the recording level is not limited to the C1 error, and other parameters may also be used. For example, as shown in FIG. 15, instead of the C1 error detection circuit 23, a frame synchronization signal detection and counter circuit 140 is provided. A frame synchronization signal detection circuit 140a and a counter circuit 140b for counting the detection frequency of the frame synchronization signal detected by the frame synchronization signal detection circuit 140a are provided instead of the C1 error value. The detection frequency of the frame synchronization signal counted by the counter circuit 140b can be used to obtain the recording speed. Here, similarly to the foregoing embodiment, the frame synchronization signal detection circuit 140a and the counter circuit 140b perform EFM-modulation on the reproduced signal of the test recording area, and simultaneously detect the EFM frame synchronization signal from the obtained signal, count the detection frequency, and control The device 16 outputs the counting result.

A method of using the detection frequency of the frame synchronization signal instead of the C1 error value includes obtaining the detection frequency of the frame synchronization signal and a plurality of recording speeds as shown in FIG. 16A for the detection frequency of the frame synchronization signal supplied from the detection circuit 140. The β value of each of them depends on the relationship between the β values supplied from the β detection circuit 24 . The method also includes: obtaining the upper limit SPJ1, SPJ2, SPJ3 and the lower limit SPK1, SPK2, SPK3 of the β value for each recording speed (V1, V2, V3), so as to obtain the frame synchronization signal ( For example, the detection frequency range of 90 or more), therefore, the satisfactory recording level as shown in FIG. This characteristic indicates the relationship between the recording speed and the value βm indicating the range of the β value. After the recording speed β value range is obtained by this method, the maximum recording speed can be obtained by using a recording speed generating part similar to that in this embodiment.

In addition, as shown in FIG. 17, a jitter detection circuit 160 is provided instead of the C1 error detection circuit 23, and the recording speed can be obtained using the jitter value detected by the jitter detection circuit 160 instead of the C1 error value. . Here, the jitter detection circuit 160 has an equalizer, a limiter, a phase locked loop (PLL) circuit, and a jitter measurement unit. The RF signal provided by the RF amplifier 12 passes through the equalizer, and the signal passed through the equalizer is binarized by the limiter, and then the binary RF signal is applied to the PLL circuit and the jitter measurement unit. In the PLL circuit, the clock signal is generated from the binary RF signal, and the generated clock signal is sent to the jitter measurement unit, which measures the jitter as the standard deviation and deviation of the recording bit and the reference length deviation of the binary RF signal.

A method of using a jitter value instead of a C1 error value includes: obtaining a jitter value and a β value for each of a plurality of recording speeds as shown in FIG. 18A from the jitter value provided by the jitter detection circuit 160 and detecting by β Circuit 24 provides the relationship between the values of β. Also include: for each recording speed (V1, V2, V3), obtain the upper limit value JPJ1, JPJ2, JPJ3 and the lower limit value JPK1, JPK2, JPK3 of the β value, in order to obtain the satisfactory recording level shown in previous FIG. 18B The range of the jitter value obtained by the experiment (in this embodiment, the jitter value is 35 or below); and using the function (in this example, a linear function) obtained by the previous experiment to obtain the indicated recording speed and the indicated β value range The relationship between the value of βm and the range characteristic of the recording speed β. After obtaining the recording speed β range characteristic by this method, the recording maximum speed can be obtained similarly to the recording speed generating section in the embodiment.

Furthermore, as shown in FIG. 19 , a deviation detection circuit 180 is provided instead of the C1 error value detection circuit 23 . And the recording speed can be obtained by using the deviation value detected by the deviation detection circuit 180 instead of the C1 error value. Here, the deviation detection circuit 180 has an equalizer, a limiter, and a PLL circuit similarly to the jitter detection circuit 160 . In addition, instead of the jitter measurement unit, a deviation measurement unit is provided for detecting deviation (record bit and reference length deviation) between the clock supplied from the PLL circuit and the binary RF signal supplied from the limiter.

A method of using an offset value instead of a C1 error value includes: obtaining an offset value and a β value for each of a plurality of recording speeds shown in FIG. 24 provides the relationship between the β values, the method also includes: upper limit values DPJ1, DPJ2, DPJ3 and lower limit values DPK1, DPK2, DPK3 for each recording speed (V1, V2, V3), so as to be maintained as The range (in this embodiment, -20≤deviation value≤20) of the deviation value obtained by the previous experiment of the satisfactory recording level shown in Figure 20B; The recording speed β range characteristic indicating the relationship between the value βm of the range of β values. After obtaining the recording speed β value range characteristic by this method, similar to the recording speed generation part of this embodiment, the recording maximum speed can be obtained.

In addition, instead of the C1 error value, when reproducing the test recording area, parameters supplied from the RF amplifier 12, such as the amplitude, modulation degree, and reflectance of the RF signal, can be used to obtain the recording speed. Here, the relationship between the amplitude value of the RF signal and the β value has a characteristic that the amplitude value increases as the β value rises, and the amplitude value increases to a certain extent until it reaches a value as shown in FIG. 21A. saturation. Similar to the above-described embodiment, the described characteristics were obtained for each of a plurality of recording speeds, i.e., the values of β obtained from previous experiments within the range of RF signal amplitudes could be obtained for each recording speed. Upper and lower limit values. Thereafter, the recording speed can be obtained similarly to the above-mentioned embodiment.

Also, the relationship between the degree of modulation and the value of β has characteristics similar to the amplitude of the RF signal shown in FIG. 21B. Similar to the foregoing embodiment, the above-mentioned characteristics can be obtained for each of a plurality of recording speeds, and the upper limit and lower limit. Then, similarly to the above-mentioned embodiment, the recording speed can be obtained. In addition, assuming that the maximum value of the RF signal is Imax and the minimum value is Imin, the modulation degree is obtained from the relational expression of modulation degree=(Imax−Imin)/Imax.

In addition, the relationship between the reflectance and the β value has the characteristics of a linear function in which the reflectance decreases as the β value increases as shown in FIG. 21C. Similar to the above-mentioned embodiment, the characteristics are obtained for each of a plurality of recording speeds, and the upper and lower limits of the β value in the reflectance range obtained by previous experiments can be obtained for each recording speed value. After that, similarly to the above-described embodiment, the recording speed can be obtained. Alternatively, the RF signal can be passed through a low-pass filter and averaged to obtain the reflectance.

Furthermore, in the above-described embodiment, the relationship between each parameter instead of the C1 error value and the β value can be obtained, and then the recording speed can be obtained. However, as described in the modified example, the relationship between each parameter and the writing laser power value can be obtained in order to obtain the recording speed.

In addition, various recording speeds can be obtained using various parameters (eg, C1 error value and jitter value). For example, when obtaining the maximum recording speed, the lower speed among the recording speeds obtained by the two parameters can be used as the maximum recording speed. When obtaining the minimum recording speed, the higher speed among the recording speeds obtained using the two parameters can be used as the minimum recording speed.

(improvement example 5)

Also, in the foregoing embodiments, an example using a CD-R as the optical disc D has been described. However, the present invention can also be used for recording on CD-RW, DVD-R, DVD-Random Access Memory (DVD-RAM) and the like.

(improved example 6)

Furthermore, the controller 16 for performing recording processing including the process of measuring the recording speed may be constituted by a specially used hardware circuit. In addition, when the controller 16 is constituted by a central processing unit (CPU) or the like, processing can be realized by software by executing a program stored in, for example, a read only memory (ROM). When processing is performed by software using the above method, various recording media that can realize recording processing with a computer, such as CD-ROM and floppy disk, are available to users, or programs can be provided to users through transmission media such as the Internet.

As described above, according to the first aspect of the present invention, it is possible to measure the recording speed range with some recording errors when recording to a certain optical disc.

B-1 Configuration of the second embodiment

The second embodiment of the present invention is basically the same in some constitutions as the first embodiment. Therefore, referring to Fig. 1, there is provided an explanation of the composition of the optical disc recording/reproducing device according to the second embodiment of the present invention. As shown in Fig. , servo circuit 13, address detector circuit 14, decoder 16, controller 16, encoder 17, countermeasure circuit 18, laser driver 19, laser power control circuit 20, frequency generator 21, envelope detection circuit 22, C1 detection Circuit 23 and β detection circuit 24.

The spindle motor 11 is a motor for rotating/driving an optical disc (eg, CD-R) D for recording data. The light receiver 10 has a laser diode, an optical system such as lenses and mirrors, and return light receiving elements. During recording and reproduction, the optical receiver irradiates the optical disc D with a laser beam, receives returning light from the optical disc D, and outputs an RF signal subjected to 8-14 modulation (EFM) as a light reception signal of the RF amplifier 12 . In addition, the optical receiver 10 has a monitor diode, and the light returned from the optical disk D generates a current in the monitor diode, and supplies the current to the laser power control circuit 20 .

Described RF amplifier 12 amplifies the RF signal from optical receiver 10, and is subjected to WFM modulation, and to servo circuit 13, address detection circuit 13, envelope detection circuit 22, β detection circuit 24 and decoder 15 output via amplified RF signal. The decoder 15 performs EFM demodulation on the modulated RF signal from the RF amplifier 12, and generates reproduced data upon reproduction.

On the other hand, when recording, the decoder 15 performs EFM demodulation on the RF signal provided by the RF amplifier 12 when reproducing the test recording data, and the C1 error detection circuit 23 detects a C1 error based on the demodulated signal, and outputs the error to the controller. Described C1 error detection circuit 23 utilizes the error correction code of so-called interleaved reading Solomon code (CIRC), makes EFM demodulated signal subject to error correction, and detects that the first error correction cannot be carried out in a subcode frame (98EFM frame) The number of frames, that is, the frequency of C1 errors.

According to the optical disc recording/reproducing apparatus of the second embodiment of the present invention, its constitution can be used to adopt the recording speed that is set by the user to carry out test recording in the predetermined area (see Fig. 2) of the inner circumference side of optical disc D before normal recording, and When performing recording as above, a recording speed for satisfactory recording on the optical disk D is obtained from the reproduction result of the test recording area. In the test recording with the optical disc recording/reproducing apparatus, the writing laser power value was changed in 15 stages, and the EFM signal was recorded for one subcode frame of one writing laser power value, and all the EFM signals were recorded for 15 frames .

Here, the area where the test recording of the optical disc D (CD-R) is performed will be described again with reference to FIG. 2 . The area of the optical disc D having a diameter of 46-50mm is taken as the lead-in area 114, and the program area 118 for recording data and the remaining area 120 are prepared on the outer peripheral side of the lead-in area. On the other hand, there is also an inner peripheral side power correction area (PCA) 112 . The PCA area 112 on the inner peripheral side includes a testing area 112a and a counting area 112b. The test area 112a is subjected to test recording prior to the normal recording process. Here, an area where a large amount of test recording is performed is taken as the test area 112a, and an EFM signal of a portion of the test area 112a indicating end of recording is recorded in the count area 112b at the end of the test recording. Therefore, when the optical disc D is subjected to test recording, the EFM signal of the count area 112b is read out. Thus, the location of the test area 112a where test recording is performed can be seen. In the optical disk recording/reproducing apparatus of the present invention, the test area 112 has been subjected to test recording before normal recording.

Returning again to FIG. 1, the address detection circuit 14 extracts a wobble signal component from the EFM signal provided by the EF amplifier 12, and decodes time information (address information) indicating each position included in the wobble signal component, identifying information (disc ID) is used to identify the disc and the disc type, such as the dye of the disc, and output the information to the controller 16.

The β detection circuit 24 calculates the β value as a parameter of the reproduction recording level with respect to the EFM modulated RF signal supplied from the RF amplifier 12 when reproducing the test recording area, and outputs the calculation result to the controller 16. The β value is determined using the equation (a+b)/(a-b), where the letter a represents the peak level (+ sign) and the letter b represents the bottom level (- sign) of the signal waveform subjected to EFM modulation.

The envelope detection circuit 22 detects the envelope of the EFM signal of the count area 112b of the optical disc D to detect a portion of the predetermined test area of the optical disc D where test recording is started before parameter recording.

The servo circuit 13 performs rotation control of the spindle motor 11, as well as focus control, tracking control and feedback control of the optical receiver 10. In the optical disc recording/reproducing apparatus of the present invention, recording is performed by a constant linear velocity (CLV) method, and the optical disc D is driven at a linear recording speed set by the user. The servo circuit 13 performs CLV control for driving the spindle motor at a set linear speed in accordance with a control signal supplied from the controller 16 indicating the set speed. Here, in the control of the CLV by the servo circuit 13 , the spindle motor 11 is controlled so that the linear velocity is amplified so that the dither signal of the EFM modulation signal is supplied from the RF amplifier 12 .

The encoder 17 performs EFM modulation on the supplied recording data, and outputs the data to a strategy circuit 18 (strategy circuit). Countermeasure circuit 18 performs processing such as time axis correction on the EFM signal supplied from encoder 17 , and outputs the signal to laser driver 19 . The laser driver 19 drives the laser diode of the optical receiver 10 in accordance with the signal modulated with the recording data supplied from the countermeasure circuit 18 and controls the laser power control circuit 20 .

The laser power control circuit 20 controls the laser power emitted from the laser diode of the optical receiver 10 . Specifically, the laser power control circuit 20 controls the laser driver 19 based on the current value supplied from the monitor diode of the optical receiver 10, and information indicating an optimum target value of the laser power supplied from the controller 16, so that 10 Launch a laser beam with optimum laser power.

First, the controller 16 controls the various device components so as to perform the above-mentioned test recording for a predetermined area of the optical disc D set in the optical disc recording/reproducing apparatus before the normal recording as described above. Furthermore, the controller 16 determines the value of the reproduction parameter by the user based on the β value detected by the β detection circuit 24, and the count value of the detection frequency of the C1 error detected by the C1 error detection circuit 23 and the like (hereinafter referred to as the C1 error value). The recording speed that the signal that obtains when recording area is set carries out the optimal writing laser power value of recording usefulness, and controls laser power control circuit 20, makes when carrying out normal recording, the laser beam that emits from optical receiver 10 has definite The best laser power value. Figure 22 illustrates the key structure of the process used by the controller 16 to obtain the optimum writing laser power value.

As shown in Figure 22, the controller 16 has a C1 error preferred value information storage 250, a β preferred value information storage 251, a laser power value regulation part 252, a laser power range regulation part 253, and an optimum laser power value determination part 254 .

Said laser power specification section 252 obtains the difference between the indicated writing laser power value and the β value obtained from the result obtained from OPC (a plurality of writing laser power values and β values corresponding to the respective laser power values) before normal recording. Relational power-beta characteristics of records. The laser power value specifying section 252 specifies the write laser power value information based on the recording power-β characteristic, the β preferred value information stored in the β preferred value information storage 251, and the disc type information provided from the address detection circuit 14. power value. As shown in FIG. 23, for each type (manufacturer, dye, etc.) of the optical disc D, in the β preferred value storage 251, β preferred value information indicating the β value for performing optimum recording is stored, and the β value is stored. ="0" is used as the preferred value information of the β value for the A-type optical disk in this example. Here, the information stored in the beta preference memory 251 is a value obtained for different types of optical discs by previous experiments. In addition, not only a preferred β value can be stored for each type of optical disc, but also can be stored in the β preferred value memory 251 for each recording speed (1x speed, 4x speed, 8x speed).

For example, when the OPC result (corresponding to the β value and the C1 error value of 15 types of writing laser power values) is obtained as shown in FIG. Enter the β power characteristic of the relationship between the β value expressed by the laser power value and the β value of the OPC result. In addition, the laser power value specifying section 252 obtains the β preference information of the disc type information supplied from the address detection circuit 14 corresponding to the β preference information of a large number of disc types stored in the β preference storage 251 . Also, when storing the preferred β value of each recording speed (1x speed, 4x speed, 8x speed, ...) in the β preferred value storage 251, the β preferred value corresponding to the set recording speed can be obtained. value information. In addition, the laser power value specifying section 252 refers to the β-power characteristic obtained according to the OPC structure (see, FIG. 25 ), and specifies a write laser corresponding to the β value indicated by the obtained β preferred value information. Power value Pt.

The laser power range specifying section 253 obtains the value indicating the writing laser power and the C1 error value obtained from the results (a plurality of writing laser power values and C1 error values corresponding to the respective laser power values) obtained by OPC before normal recording. The write power-C1 error characteristic laser power range regulation part 253 of the relationship between the possible upper and lower limit values of the write laser power, that is, one based on the write power-C1 error characteristic stored in the C1 error preferred value The C1 error preferred value information in the memory 250 and the range of possible values of the write laser power for the disc type information provided by the address detection circuit 14 . As shown in FIG. 26, in the C1 error preference value memory 250, C1 error preference value information indicating the possible range of the C1 error value for performing optimum recording is stored for each type (manufacturer, dye, etc.) of the optical disc D. , store the C1 error value = "0-10" as the C1 error preferred value information for the A-type optical disc of the embodiment. In addition, in the C1 error preferred value memory 250, not only for each type of optical disc but also for each recording speed (1x speed, 4x speed, 8x speed, . range of information.

For example, when the OPC result as shown in FIG. 24 is obtained, the laser power range specifying section 253 obtains the C1 error indicating the writing laser power value and the C1 error value from the writing laser power value as shown in FIG. 27 and the OPC result. Power-C1 error characteristics of the relationship between values. Also, laser power range specifying section 253 obtains C1 error value information from disc type information supplied from address detection circuit 14 corresponding to C1 error preferred value information of a large number of disc types stored in C1 error preferred value storage 250 . In addition, the preferred range of C1 error values for each recording speed (one-time speed, four-time speed, eight-time speed...) is stored in the C1 error preferred value storage 150, and the C1 error corresponding to the set recording speed can be obtained. Preferred value information. Also, the laser power range specification part 253 refers to the power-C1 error characteristic (see, FIG. 27 ) obtained according to the OPC result, and obtains the C1 error value set at the C1 error indicated by the obtained C1 error preferred value information. The upper limit value PJ (being 16mv in the present embodiment) and the lower limit value PK (being 13mv in the present embodiment) of the writing laser power in the value range, and stipulate possible range Pm (writing laser power 13-16mv).

The optimum laser power value determination section 254 determines the optimum writing according to the write laser power value Pt specified by the laser power specification section 252 and the effective range Pm of the write laser power specified by the laser power range specification section 253 as described above. Laser power value. Specifically, the optimum laser power value determining section 254 judges whether the writing laser power value specified by the laser power value specifying section 252 is within the valid range Pm of the writing laser power value specified by the laser power range specifying section 253 . When it is determined that the writing laser power value is within the range Pm, the writing laser power value Pt is determined as the optimum writing laser power value. On the other hand, when the writing laser power value Pt is within the range of Fm, OPC is performed again, and a process similar to the above method can be used to determine the optimum writing laser power value based on the OPC result. However, when the writing laser power value is not within the range of Pm, the determination method includes: determining the average value of the writing laser power value Pt and the upper limit value PJ or the lower limit value PK (close to the writing laser power value Pt) as Optimum writing laser power value. Thus, it is possible to determine an optimum writing laser power value in consideration of not only the β value but also the C1 error value.

The controller 16 provides the laser power control circuit 20 as shown in FIG. The power value of the recording laser beam emitted by the device 19 to the optical disk D is consistent with the optimum writing laser power value.

B-2. Operation

The structure of the optical disc recording/reproducing apparatus according to the second embodiment of the present invention has been described above. The operation of recording time by the optical disk recording/reproducing apparatus constructed as described above will be described with reference to a flowchart of a process executed by the controller 16 shown in FIG. 28 in accordance with a program stored in the ROM.

First, the user sets the optical disc D in the optical disc recording/reproducing apparatus, and instructs to start recording at a certain recording speed. Then, the controller 16 controls the respective device components to perform parameter recording in the test area 112a of the optical disk D using OPC (step Sb1). Specifically, a signal for test recording is sent to the encoder 17, and the laser power control circuit 20 is controlled so that the writing laser power value is changed in 15 steps. The components of each device are controlled in such a way that EFM signals for one subcode frame are recorded for each write laser power value, and test recording is performed for all 15 frames of EFM signals.

In controlling the respective components to perform the test recording, the controller 16 determines the optimum writing laser power value as described above based on the OPC result obtained from the reproduced signal of the test recording area (step Sb2). Thereafter, the controller 16 controls the laser power control circuit 20, the servo circuit 13, etc., so that recording is performed at the recording speed set by the user and the optimum laser power value determined as described above, and the recording process is performed corresponding to the optical disc D (step Sb3) .

In this embodiment, the test recording is performed before the normal recording, and the optimum writing laser power value is determined based on the β value and the C1 error value indicating the level of the recording state obtained from the reproduced signal of the test recording, and the measured writing laser power value can be used. Enter the laser power value for recording. That is, the optimum writing laser power value is determined considering only the β value in the commonly used OPC. However, according to the present invention, it is possible to determine an optimum writing laser power value in consideration of not only the β value but also the C1 error value. Therefore, it is possible to reduce recording level deterioration due to product differences (curl, warp, dye unevenness, etc.) among individual optical discs D, compared with the power measurement method that only considers the β value. For example, when recording at a writing laser power value corresponding to a β-effective point is performed using an optical disc having a β-value-effectively changing point characteristic for β-value effectively changing (see FIG. 48 ). However, sometimes a satisfactory level of recording status cannot be obtained. However, in this embodiment, not only the β value but also other parameters related to the recording level are taken into consideration to determine the optimum writing laser power value. Therefore, deterioration of the recording level caused by the β change point can be suppressed.

B-3 Improvement example

The second embodiment can be modified in various ways as follows.

B-3-1 Improvement example 1

The method of the second embodiment comprises:

Corresponding to a plurality of writing laser power values, a β value and a C1 error value are measured from a reproduced signal of a test recording area; and an optimum laser power value is determined using these parameters. However, the method may include: obtaining other parameters for the quality of the recorded state from the reproduced signal of the test recording area; and determining an optimum writing laser power value using the obtained parameters.

For example, as shown in FIG. 15, a frame synchronization signal detection circuit 140a and a counter circuit 140b are used instead of the C1 error detection circuit 23 in the second embodiment. In addition to the β value, an optimum write laser power value can be determined using the frame synchronization signal detection frequency detected by the frame synchronization signal detection circuit 140a and the counter circuit 140b. Here, similarly to the second embodiment, the frame synchronization signal detection circuit 140a and the counter circuit 140b EFM-modulate the reproduced RF signal of the test recording area, and detect the EFM frame synchronization signal from the obtained signal, and count the detection frequency, and The frequency is output to the controller 16 .

When using the detection frequency of the frame synchronization signal to replace the C1 error value, that is, when using the β value and the detection frequency of the frame synchronization signal to determine the optimum writing laser power value, similar to the second embodiment, first, from the frame synchronization signal detection The detection frequency of the frame synchronization signal supplied from the circuit 140a and the counter circuit 140b, and the β value supplied from the β detection circuit 24 obtain a writing power-β characteristic indicating a relationship between the writing laser power value and the β value. In addition, as shown in FIG. 29 , a write power-frame sync signal detection frequency characteristic indicating the relationship between the write laser power value and the frame sync signal detection frequency was obtained.

The method further includes: similar to the second embodiment, specifying the writing laser power value Pt corresponding to the β value indicated by the pre-stored β preferred value information; referencing the writing power-frame synchronization signal detection shown in FIG. 29 Frequency; obtain the possible range SPm of setting the frequency and specifying the writing laser power within the range indicated by the pre-stored frame synchronization signal detection frequency preference value information (in this embodiment, the frame synchronization signal detection frequency is 90 or more) The upper limit SPJ (16.5 mW in this embodiment) and the lower limit SPK (12.5 mW in this embodiment) of the writing laser power used were used.

When specifying the write laser power value Pt from the β value, the possible range of the write laser power is specified by the frame synchronization signal detection frequency, and as in the second embodiment, the write laser power value Pt is within the SPm range, and The writing laser power value Pt is determined as the optimum writing laser power value. On the other hand, when the writing laser power value Pt is not within the range SPm, the OPC is performed again, and the process of determining the optimum writing laser power value can be performed according to the OPC result similar to the above. However, when the writing laser power value Pt is not within the range of SPm, the measurement method includes: measuring the average value of the writing laser power value Pt and the upper limit value SPJ or the lower limit value SPK (close to the writing laser power value Pt) as Optimum writing laser power value. Therefore, not only the β value but also the detection frequency of the frame synchronization signal can determine the optimum writing laser power value.

In addition, as shown in FIG. 17, a jitter detection circuit 160 is provided instead of the C1 error detection circuit 23, so the optimum writing laser power value can be determined by the jitter value detected by the jitter detection circuit 160 instead of the C1 error value. Here, the jitter detection circuit 160 includes an equalizer, a limiter phase-locked loop (PLL) circuit, and a jitter measurement part. The RF signal supplied from the RF amplifier 12 passes through the equalizer, and the signal passed through the equalizer is binarized by the limiter. Additionally, a binary RF signal is applied to the PLL and jitter measurement components. In the PLL circuit, a clock signal is generated from a binary RF signal, and the generated clock signal is sent to a jitter measurement unit. The jitter measurement means measures jitter from the clock and the binary RF signal as a standard deviation of recorded bits and a reference length deviation.

When using the jitter value instead of the C1 error value, that is, when using the β value and the jitter value to measure the optimum writing laser power value, first, similar to the second embodiment, obtain the indicated writing laser power value and from the jitter detection The write power-β characteristic of the relationship between the jitter value supplied from the circuit 160 and the β value supplied from the β detection circuit 24 (see, FIG. 25 ) and the β value supplied from the β detection circuit 24. In addition, as shown in FIG. 30, it is also possible to obtain the write power-jitter characteristic indicating the relationship between the write laser power value and the jitter value.

The method further includes: similar to the second embodiment, specifying a writing laser power value Pt corresponding to the β value indicated by the pre-stored β preferred value information (see, FIG. 25 ); referring to FIG. 30 Write power-jitter characteristics; And obtain the upper limit value JPJ (being 16.9mW in this example) and the lower limit value JPK (being 12.1mW in this example) of writing laser power, be used for this value to be set in by preset It is stored within the range indicated by the preferred jitter value information (in this example, the jitter value is 35 or less), and the possible range JPm of the writing laser power is specified.

When the writing laser power value Pt is specified from the β value in this way, the possible range JPm of the writing laser power value is specified by the jitter value, and as in the second embodiment, the writing laser power value Pt is within the range JPm, and This writing laser power value Pt is taken as the optimum writing laser power value. On the other hand, when the write laser power value Pt is not within the range JPm, OPC is performed again, and the process of determining the optimum write laser power value can be performed based on the OPC results similar to those described above. In addition, when the write laser power value Pt is not within the range JPm, the measurement method includes taking the average value of the write laser power value Pt and the upper limit value JPJ or the lower limit value JPK (closer to the write laser power value) as the optimum value. Write the laser power value.

In addition, as shown in FIG. 19 , the C1 error detection circuit 23 is replaced by a deviation detection circuit 180 , and the optimum writing laser power value can be determined using the deviation value detected by the deviation detection circuit 180 . here. Deviation detection circuit 180 includes an equalizer, a limiter and a PLL circuit similar to jitter detection circuit 160 . Also, instead of the jitter measuring section, a clock signal supplied from the PLL circuit and a binary RF signal supplied from the limiter are used to perform offset measurement (deviation of recording bit and recording length) by the offset measuring section.

When using the offset value instead of the C1 error value, that is, when using the β value and the offset value to measure the optimum writing laser power value, first, similar to the second embodiment, the writing power-β characteristic (see, FIG. 25 ) indicates the relationship between the writing laser power value and the β value obtained from the deviation value supplied from the deviation detection circuit 180 and the β value supplied from the β detection circuit 24 . Whereas, the writing power-deviation characteristic indicates the relationship between the writing laser power value and the deviation value shown in FIG. 31 .

The method further includes: specifying the laser power value Pt (see, FIG. 25 ) written by corresponding to the β value indicated by the pre-stored β preferred value information similar to the second embodiment; referring to the writing shown in FIG. 31 Power-deviation characteristics; and obtaining an upper limit value DPJ (14.5mW in this example) and a lower limit DPK (12mW in this example) of the write laser power for use by pre-stored deviation preferred value information indication The value of is set within the range (in this example, the deviation value of -20-20), and specifies the possible range DPm of the writing laser power.

When the writing laser power value Pt is specified by the β value in this way, the possible range DPm of the writing laser power value is specified by the deviation value, and the writing laser power value Pt is located within the range DPm similar to the second embodiment, The writing laser power value can be regarded as an optimum writing laser power value. On the other hand, when the writing laser power value is not within the range DPm, OPC is performed again, and a process similar to the above-mentioned optimum writing laser power value determination is performed according to the OPC result. In addition, when the writing laser power value is not within the range DPm, the determination method includes measuring the average value of the writing laser power value Pt and the upper limit value DPJ or the lower limit value DPK (closer to the writing laser power value Pt) as the maximum value. Optimum writing laser power value.

In addition, instead of the C1 error value, the optimum write laser power value can be determined using, for example, the amplitude, modulation degree, and reflectance of the RF signal supplied from the RF amplifier 12 when reproducing the test recording area as parameters. Here, the relationship between the writing laser power value and the amplitude value of the RF signal is based on the characteristic that the amplitude value rises as the writing laser power value rises, and saturates when the amplitude value rises to a certain extent, As shown in Figure 32. In determining the optimum write laser power value using the RF amplitude value, write power-amplitude characteristics were obtained from the RF signal supplied from the RF amplifier 12 when reproducing the test recording area as described above. The method also includes: referencing the obtained characteristics; the upper limit value RPJ and the lower limit value RPK of the writing laser power obtained by obtaining are used to set the writing laser power at the pre-stored value of the amplitude of the RF signal It is within the range indicated by the preferred value information, and specifies the possible range RPm of the writing laser power value. In addition, similarly to the second embodiment, the optimum writing laser power value can be determined from the range RPm and the writing laser power value Pt specified by the β value.

In addition, the relationship between the degree of modulation and the writing laser power value has a relationship similar to that between the amplitude of the RF signal and the writing laser power value shown in FIG. 33 . When using the modulation degree to determine the optimum writing laser power value, the writing power-modulation degree characteristic can be obtained from the RF signal provided by the RF amplifier 2 when reproducing the test recording area as described above. The method further includes: referring to the obtained characteristics; obtaining an upper limit value HPJ and a lower limit value HPK of the writing laser power, and setting the writing laser power at the value indicated by the pre-stored preferred value information of the degree of modulation Within the range, and stipulate the possible range HPm of writing laser power value. In addition, similar to the second embodiment, the optimum writing laser power value can be determined from the range HPm and the writing laser power value Pt prescribed from the β value similar to the second embodiment. Also, assuming that the maximum value of the RF signal is Imax and the minimum value is Imin, then the modulation degree is obtained by using the modulation degree formula, modulation degree=(Imax−Imin).

Also, the relationship between the reflectance and the writing laser power value has the characteristic of a linear function, wherein the reflectance decreases as the writing laser power value increases, see FIG. 34 . When determining the optimum writing laser power value using reflectance, the writing power-reflectance characteristic can be obtained from the RF signal supplied from the RF amplifier 12 when reproducing the test recording area as described above. The method further includes: referencing the obtained characteristics; obtaining an upper limit value HSPJ and a lower limit value SHPK of the writing laser power, for setting the writing laser power at the value indicated by the pre-stored preferred value information of the reflectivity Within the range, and stipulate the possible range of writing laser power value HSPm. In addition, similarly to the second embodiment, the optimum writing laser power value can be determined from the range HSPm and the writing laser power value Pt specified from the value of β. Also, the reflectivity can be obtained from the RF signal supplied from the RF amplifier 12 and the average signal.

B-3-2 Improvement example 2.

In the second embodiment and the previous modified example, the writing laser power value of a certain point is specified from the β value obtained according to the result of the test recording, and from other parameters (C1 error value, detection frequency of the frame synchronization signal, jitter value, offset value, RF signal amplitude, modulation degree and reflectivity) to obtain the possible range of writing laser power values. However, the shown method may include: using other parameters to specify the writing laser power value of a point; and using the β value to specify the possible range of writing laser power.

In addition, the method may include: using two or more parameters, such as the level of the recording state, such as the C1 error value, the detection frequency of the frame synchronization signal, the jitter value, the amplitude of the RF signal, the degree of modulation and the reflectivity, to Determine the optimum writing laser power value. For example, the method may include: using the C1 error value to specify a writing laser power value; using the detection frequency of the frame synchronization signal to specify the possible range of the writing laser power value; and according to the specified writing laser power value and range To determine the best writing laser power value.

In addition, in the second embodiment, the writing laser power value at a point can be specified by a parameter (for example, the β value in the second embodiment), and the possible range of the writing laser power value is determined by other parameters (in the second embodiment The C1 error value in the embodiment) stipulates. When the predetermined writing laser power value specified by the parameter is within the range specified by other parameters, the writing laser power value at one point is taken as the optimum writing laser power value. However, the optimum writing laser power value can also be determined by other methods. For example, the average value of the writing laser power value specified from the β value and the writing laser power value at a point specified from the C1 error value is taken as the optimum writing laser power value.

Also, two parameters related to the recording state level, such as β value and C1 error value, can be used to obtain the optimum writing laser power value. However, three or more of the aforementioned parameters (C1 error value, detection frequency of frame synchronization signal, jitter value, offset value, amplitude of EF signal, degree of modulation and reflectivity) may also be used. For example, when using three parameters, such as the β value, the C1 error value, and the detection frequency value of the frame synchronization signal, similar to the second embodiment to obtain the optimum writing laser power value, the writing laser power value Pt is specified by the writing power-characteristic (see, FIG. 25), and the possible range of the writing laser power value is obtained from the writing power-C1 error characteristic and the writing power-frame synchronization signal detection frequency characteristic. For example, as shown in FIG. 35, when the possible range of the writing laser power value is specified by the writing power-C1 error value, the possible range SPm of the writing laser power value is specified by the writing power-frame synchronization signal detection frequency, and The optimum writing laser power value can be specified according to the range KPm of the partial range Pm superimposed on the range SPm (range KPm=range Pm in this example), and the writing laser power value Pt.

C. The third embodiment

An optical disc recording/reproducing apparatus according to a third embodiment of the present invention will be described below with reference to FIGS. 36 and 37. FIG. As shown in FIG. 36, the optical disc recording/reproducing apparatus according to the third embodiment of the present invention is different from the optical disc recording/reproducing apparatus according to the second embodiment of the present invention in that the beta detection circuit 24 is not provided in the second embodiment. The C1 error detection circuit measures a C1 error using an RF signal supplied from the 1RF amplifier 12 when reproducing a test recording area similar to that in the second embodiment, and outputs a C1 error value as a measurement result to the controller 16.

The controller 16 in the third embodiment differs from the controller 16 in the second embodiment in the method of determining the optimum writing laser power value. FIG. 37 shows the functional structure of the controller 16 in the process of determining the optimum writing laser power value by the controller 16 in the third embodiment. As shown in FIG. 37 , the controller 16 has a C1 error preferred value storage 220 and an optimum writing laser power value determination section 221 .

The optimal write laser power value determination part 221 obtains the indicated write laser power value and the result obtained by OPC carried out before normal recording (a plurality of write laser power values and C1 corresponding to the write laser power value) The writing power-error characteristic of the relationship between the C1 error value shown in FIG. 38 ). The optimum write laser power value determining section 221 specifies the write laser power value based on the C1 error preference value information stored in the C1 error preference value memory 220 and the disc type information supplied from the address detection circuit 14 . In the C1 error preferred value storage 220, jitter preferred value information indicating the C1 error value for performing optimum recording is stored for each type (different manufacture and dye) of the optical disc D. Here, the information stored in the C1 error preference value storage 220 is a value obtained for each disc by previous experiments.

When obtaining the power-C1 error characteristic indicating the relationship between the writing laser power value and the C1 error value shown in FIG. 38, the optimum writing laser power value determination section 221 can obtain The C1 error preference value information CJK (may be equal to 0) corresponding to the disc type is provided from the address detection circuit 14 of a large number of disc types in the device 220. In addition, the optimum write laser power value determination section 221 refers to the power-C1 error characteristic obtained from the OPC result, and measures the write laser power value Pt' corresponding to the C1 error value indicated by the obtained error value information. Also, the controller 16 controls the respective device components of the laser power control circuit 20 so that the laser beam having the measured writing laser power value Pt' is emitted from the optical receiver 10 to the optical disk D.

According to the third embodiment, the optimum writing laser power value can be determined by considering the C1 error value instead of the β value as a parameter. For example, recording is performed at a writing laser power value corresponding to the β effective point for an optical disc having a characteristic of an effective point of change at the β value. Thus, a satisfactory recording state level cannot be obtained in some cases. However, in the present embodiment, the part determines the optimum write laser power value in consideration of the β value, but also in consideration of other water related recording states. Therefore, deterioration of the recording state level caused by the β effective point can be suppressed.

Also, in the third embodiment, the C1 error detection circuit 23 is provided to detect the C1 error value from the reproduced signal of the test recording area, and takes the write laser power value at the C1 error value indicating the pre-stored preferred value as the final value. Optimum writing laser power value. However, the method may include: detecting parameters related to the recording state, such as the jitter value, the detection frequency of the frame synchronization signal, the deviation value and the level of the amplitude of the RF signal; and determining the optimum writing using any one of these parameters Laser power value.

Also, in the third embodiment, the writing laser power value Pt' corresponding to the preferred value CJK of the C1 error value stored in the C1 error preferred value storage 220 is used as the optimum writing laser power value. However, when the optimum writing laser power value is determined not from the β parameter but from other parameters, the following method can be used.

For example, when the detection frequency of the frame synchronization signal is detected from the RF signal of the test recording area, the write power-frame synchronization signal detection frequency characteristic as shown by the solid line in FIG. 39 can be obtained. When obtaining this characteristic, the method for determining the optimum writing laser power value at first includes: obtaining a quadratic function close to the writing power-frame synchronization signal detection frequency characteristic ) is the result of the test record represented by the solid line. For example, when the quadratic function is represented by frame synchronization signal detection frequency (SYEQ)= ^ap2 +bp+c (wherein P represents a variable value indicating a writing laser power value, and a, b, c represent fixed values), By differentiating this quadratic function, the variable of the frame synchronization signal detection frequency per unit writing laser power=ap+b (hereinafter referred to as ΔNSYEQ) can be obtained. The relationship between ΔNSYEQ obtained in this way and the writing laser power value can be expressed by a linear function as shown in FIG. 40, referring to the writing power-ΔNSYEQ characteristic shown in FIG. The writing laser power value Pt″ with value SK is taken as the optimum writing laser power value.

Also, in order to detect the C1 error value from the signal obtained by EFM-demodulating the RF signal of the test recording area, and determine the optimum write laser power value, it is similar to determining the optimum write laser power value using the frame synchronization signal detection frequency , a quadratic function close to the write power-C1 error value characteristic as shown in FIG. 41 can be obtained by the least mean square method (by the dotted line shown in FIG. 41). For example, similar to using the detection frequency of the frame synchronization signal, the quadratic function shown is differentiated, and the write power-ΔC1 error characteristic shown in FIG. 42 is obtained. Referring to the writing power-ΔC1 error characteristic shown in FIG. 42, the writing laser power value PCt corresponding to the pre-stored preferred ΔC1 error value is determined as the optimum writing laser power value.

In addition, in the above-mentioned modified examples, a quadratic function close to writing power-frame synchronization signal detection frequency, or writing power-error characteristics is obtained by using the least mean square method. The writing laser power value at which the ΔNSYEQ or ΔC1 error characteristic represented by the linear function obtained using the differential quadratic function indicates a preferable value is taken as the optimum value. However, usable methods include: obtaining a quadratic function close to the writing power-frame synchronization signal detection frequency similar to the above; When the partial region defined by the line =0 is set as S, the write laser power value having 40% of the region S is measured. In this case, the writing laser power value with the area ratio can be obtained from previous experiments, and the area ratio obtained from the experimental results can be stored.

In addition, as shown in FIG. 44, instead of determining the optimum writing laser power value with the ratio of the region S as described above, a curve similar to the quadratic function obtained as described above and representing a preset frame synchronization signal detection frequency value ( In this embodiment, the line F50 of the frame synchronization signal detection frequency = 50) intersects as the writing laser power values PSK, PSJ. And from these values the optimum writing laser power value can be determined. For example, as shown in FIG. 44, the optimum writing laser power value PS is obtained from the following equation.

PS＝(PSJ-PSK) ^* 0.4+PSK

Using this equation, a value between the writing laser power values PSK and PSJ (value of 60% of PSJ) is obtained as the intersection value, which is 40% of PSK and can be used as the optimum writing laser power value.

In addition, using the method of detecting the detection frequency of the frame synchronization signal and the C1 error value, the minimum mean method is used to express each characteristic using a quadratic function, and the quadratic function is differentiated or the area surrounded by the quadratic function curve is obtained, and the best Write the laser power value, this method can not only be used for the determination of parameters such as frame synchronization signal detection frequency and C1 error, but also can be used for the determination of parameters such as jitter value.

D fourth embodiment

An optical disc recording/reproducing apparatus according to a fourth embodiment of the present invention will be described below. The structure of the optical disc recording/reproducing apparatus according to the fourth embodiment is basically similar to the optical disc recording/reproducing apparatus of the second embodiment except for the method of determining the optimum writing laser power value by the controller 16. Therefore, the method for determining the optimum writing laser power value by the controller 6 of the optical disc recording/reproducing apparatus of the fourth embodiment will be described below with reference to FIG. 45, which shows the process for determining the optimum writing laser power value. Functional structure of the controller 16 .

As shown in FIG. 45 , the controller 45 in the fourth embodiment has a Δβ value memory 300 , a β effective point detector 301 , and an optimum writing laser power value determination section 302 .

The β effective point detector 301 obtains the result (a plurality of laser power values and β values corresponding to the respective laser power values) indicating the write laser power value and the result obtained from the OPC before normal recording shown on FIG. 46 Write power-beta characteristics of the relationship between beta values. In addition, as shown in FIG. 47 , the writing power-Δβ characteristic indicating the relationship between the amount of change in the β value per unit writing laser power value, that is, the differential value Δβ of the β value, and the writing laser power value is obtained.

The β effective point detector 301 detects the difference in each part of the relationship between the β value and the write laser power value, that is, the β value according to the write power-Δβ characteristic has an effectively changed β effective point and stored in Δβ Δβ value information in value storage 300 . The Δβ storage 300 stores a threshold value BTS for detecting Δβ values of β effective points obtained from previous experiments. As shown in FIG. 46, the β effective point BT is a portion having a smaller Δβ value than other portions. Therefore, the portion where the detected Δβ value is smaller than the Δβ value stored in the Δβ storage 300 can be taken as a valid β point. In the example of FIG. 46 , the portion close to the write laser power value of 15-16 mW is the β effective point BT. It can be seen from FIG. 47 that the Δβ value of the portion where the β value is effective (the portion close to the writing laser power value) is smaller than the value of any other portion. The β effective point detector 301 detects the portion whose Δβ value is smaller than the threshold BTS of the Δβ value stored in the Δβ value storage 300 as the β effective point BT, and obtains the writing laser power corresponding to the β value effective point BT Value (lower limit value PBK to upper limit value PBJ).

In addition, in addition to the threshold value BTS of the Δβ value for detecting the β value effective point BT, the threshold value BCS of the Δβ value for specifying the possible range of the writing laser power value is stored in the Δβ value memory 300 . For the determination of the optimum writing laser power value, refer to the writing power-Δβ characteristic shown in FIG. BCS. Also, the optimum writing laser power value measuring section 302 measures a writing laser power value which is smaller than the writing laser power value PBK corresponding to the β value effective point BT obtained by the β effective point detector 301 as described above. , and belong to the range PBm1 and PBm2 of the writing laser power value, and the writing laser power value measured therefrom is taken as the optimum writing laser power value.

The controller 16 in the fourth embodiment controls each device component of the optical disc recording/reproducing device so that the recording is performed at the optimum writing laser power value determined above. In order to record on an optical disc having a β effective point characteristic, the optical disc to be recorded has a writing laser power value (15.5 mW in this embodiment, see FIG. 47 ) corresponding to a β value effective point with an effective change in the β value. characteristics. Therefore, a satisfactory recording level cannot be obtained in some cases. However, in the present embodiment, the Δβ value is obtained and the β effective point is detected as described above, and recording is performed while making the writing laser power value smaller than the writing laser power value corresponding to the β effective point. Therefore, deterioration of the recording level can be prevented because of the β effective point.

In addition, when the Δβ value is obtained and used to determine the optimal writing laser power value, other parameters (C1 error value, frame synchronization signal detection frequency, jitter value, deviation value, reflectivity) can be used to determine the optimal writing laser power value. For example, when the C1 error value of the frame synchronization signal detection frequency is applied in addition to the Δβ value, the possible range of the write laser power value is obtained from the write power-Δβ characteristic similarly to the fourth embodiment. Also, the possible range of the write laser power value can be obtained from the write power-C1 error characteristic and the write power-frame synchronization signal detection frequency characteristic. For example, as shown in FIG. 48, the possible range Pm of the write laser power value is specified from the write power-C1 error characteristic, and the possible range SPm of the write laser power value is specified from the write power-frame synchronization signal detection frequency characteristic, The possible range PBm of the write laser power value can also be specified from the write power-Δβ characteristic. In this case, it is possible to determine the optimum writing laser power value for the writing laser power within the range KPm of the overlapping portion of the ranges Pm, SPm, and BPm.

E improvement example

In addition, the present invention is not limited to the various embodiments described above, and various modifications as follows can be made.

In various embodiments, recording is performed by a constant linear velocity CLV method in which the spindle motor 11 drives the optical disc D at a constant linear velocity. However, recording may be performed by a CAV method in which the optical disc D is driven at a constant angular velocity. When recording is performed by the constant angular velocity CAV method, the recording linear velocity increases as the recording position goes toward the outer peripheral side of the disc. Therefore, it is necessary to change the writing laser power value according to the change of the recording linear velocity. Therefore, when recording, the described CAV method includes: in different embodiments, it is necessary to carry out the process of determining the optimum writing laser power value as described above for a plurality of recording linear velocities; Recording speed-best writing laser power characteristic corresponding to the relationship between the best writing laser power values of a plurality of recording speeds; refer to said recording speed-best power characteristic; and change according to the change of recording linear speed Optimum writing laser power value.

In addition, in the above-mentioned second and third embodiments and modified examples, two or more parameters such as the β value and the C1 error value (third embodiment) are obtained from the reproduced signal of the test recording area, and the obtained The parameter references determine the optimum writing laser power value. However, when the ability of the circuit for detecting each parameter is insufficient, and when the recording area is reproduced at the same high speed as that at which the optimum writing laser power value is obtained by recording at a high speed, the same time is used to measure a plurality of parameters. The process cannot keep up with the reproduction speed. Therefore, sometimes it is not possible to accurately obtain the reproduction parameters such as the β value and the C1 error value. Therefore, it is proposed to reduce the sampling period for obtaining parameters (eg, double the period). However, when obtaining the C1 error value, the maximum number of C1 errors is 48 (usually 98), but there is a problem of accuracy.

Considering the difficulty of accurately obtaining multiple parameters using OPC for high-speed recording, that is, performing OPC at a high recording speed, performing reproduction at a speed lower than the recording speed, and measuring multiple parameters from the reproduced signal obtained at a low reproduction speed, Thereby, multiple parameters can be obtained more accurately.

In addition, other methods include: performing OPC recording at high speed; performing multiple reproductions of the recorded area; and averaging the measured parameters of the reproduced signals obtained through multiple reproductions, so as to improve the measurement accuracy of the parameters. Also, the first reproduced signal is used only to measure the β value, and the second reproduced signal is used to obtain the C1 error value. In this way each obtained reproduction signal can be used to measure any kind of parameter. Of course, multiple reproductions may be performed at a speed lower than the recording speed.

In addition, in a different embodiment, for example, a CD-R is used as is the optical disk D described above. However, the present invention can also be used for recording of CD-RW, DVD-R, DVD random access memory (DVD-RAM), phase change-rewrite (PC-RW) and the like.

Also, the controller 16 for performing the recording process including the determination process of the optimum writing laser power value may be constituted by a dedicated hardware circuit, a central processing unit (CPU), or the like. When a program stored in a memory such as a read only memory (ROM) is executed, the processing is realized by software. When the processing is performed by software in this way, various recording media such as CD-ROM and a floppy disk in which a program for realizing processing by a computer is recorded may be provided to the user, or the program may be provided to the user through a transmission medium such as the Internet .

As described above, according to the second aspect of the present invention, it is possible to reduce the generation of recording errors regardless of the differences among the products of optical discs to be recorded.

Claims (7)

1. method of determining the power that writes light beam that tracer signal is used on CD comprises:

Recording step, by before physical record in the presumptive test district of CD tracer signal carry out test record;

Reproduce step, from the presumptive test district reproducing signal of CD;

Produce first recording characteristic according to reproducing signal, wherein said first characteristic is represented the characteristic of β value as the function that writes light beam power, and the β value is according to the amplitude acquisition of reproducing signal;

Obtain second recording characteristic from first recording characteristic, wherein said second recording characteristic is represented the characteristic of Δ β as the function that writes light beam power, and Δ β representation unit writes the variation of the β value in first characteristic of quantity of power of light beam;

Determining step uses the preferable range of Δ β to determine the recording power scope according to second recording characteristic that obtains, and the preferable range of this Δ β is scheduled to for realizing preferred record, thereby determines to write the power of light beam in the recording power scope; And

Determine to write the preferred power of light beam according to first recording characteristic and in the recording power scope.

2. method according to claim 1 also comprises:

Produce the 3rd recording characteristic according to reproducing signal, the 3rd recording characteristic represents to write the relation between the power of light beam and in a plurality of qualitative parameter relevant with the characteristic of record at least one, and is that the percentage modulation laser beam of deviation, the reproducing signal of the frequency of the frame synchronizing signal in detection is included in the reproducing signal of CD, the shake that is included in C1 error in the reproducing signal, reproducing signal, reproducing signal is selected from the parameter group that the amplitude of the reflectivity of CD and reproducing signal is formed;

Wherein determining step comprises except second recording characteristic that is obtained and also determines the recording power scope according to the 3rd recording characteristic that is produced.

3. the method for claim 1, wherein said reproduction step comprise the read-out speed reproducing signal of the signal writing rate with less than test record the time.

4. the method for claim 1 is wherein reproduced step and is comprised by carry out repeatedly the recovery time on the test section and reproduce the step of a plurality of signals.

5. the method for claim 1, wherein said determining step comprises determines to be divided into upper side and than the recording power scope of downside, and described determining step also comprise with the preferred power that writes light beam determine determined recording power scope than downside within.

6. a utilization has the device that writes light beam tracer signal on CD of preferred power, and this device comprises:

The test record part, described test record part is carried out the test record of signal in the presumptive test district of CD before physical record;

Reproducing part is from the presumptive test district reproducing signal of CD;

Produce part, described generation part produces first recording characteristic according to reproducing signal, and described first recording characteristic is represented the characteristic as the β value of the function that writes light beam power, and the β value is according to the amplitude acquisition of reproducing signal; Described generation part further produces second recording characteristic from first recording characteristic, wherein said second recording characteristic is represented the characteristic of Δ β as the function that writes light beam power, and Δ β representation unit writes the variation of the β value in first characteristic of quantity of power of light beam; And

Determining section, described determining section use the preferable range of Δ β to determine the recording power scope according to second recording characteristic, and the preferable range of this Δ β is scheduled to for realizing preferred record, thereby determine to write the power of light beam in the recording power scope; And determine to write the preferred power of light beam according to first recording characteristic and in the recording power scope.

7. a utilization has the device that writes light beam tracer signal on CD of preferred power, and this device comprises:

The test record part, described test record part is carried out the test record of signal in the presumptive test district of CD before physical record;

Reproducing part is from the presumptive test district reproducing signal of CD;

Produce part, produce first recording characteristic according to reproducing signal, described first recording characteristic is represented the characteristic as the β value of the function that writes light beam power, and the β value is according to the amplitude acquisition of reproducing signal; Described generation part produces second recording characteristic from first recording characteristic, and described second recording characteristic is represented the characteristic as the Δ β of the function that writes light beam power, and Δ β representation unit writes the variation of the β value in first characteristic of quantity of power of light beam; Described generating unit branch produces the 3rd recording characteristic according to reproducing signal, described the 3rd recording characteristic represents to write the relation between the power of light beam and in a plurality of qualitative parameter relevant with the characteristic of record at least one, and is that the deviation of the frequency of the frame synchronizing signal in detection is included in the reproducing signal of CD, the shake that is included in C1 error in the reproducing signal, reproducing signal, reproducing signal, the percentage modulation laser beam that is added to laser beam are selected from the parameter group that the amplitude of the reflectivity of CD and reproducing signal is formed; And

Determining section, described determining section uses the preferable range of Δ β to determine the recording power scope according to second recording characteristic and the 3rd recording characteristic, the preferable range of this Δ β is scheduled to for realizing preferred record, thereby determines to write the power of light beam and according to first recording characteristic, second recording characteristic and the 3rd recording characteristic and determine to write the preferred power of light beam in the recording power scope in the recording power scope.

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