JP2004192798A - Recording method and recording device of optical information - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recording method of optical information for accurately forming a recording mark having a desired length. <P>SOLUTION: An optical driving waveform 4041 is formed so that driving start time is delayed by B18(2, 2) and driving end time is advanced by E18(2, 4) respectively to a standard signal 4100. B18(2, 2) is determined as a function of a length T4101 for a last non-record part and a length T4102 for the recording mark so that the thermal state of a mark starting end is made fixed without depending on the recording pattern. E18(2, 4) is determined as a function of the length T4102 for the recording mark and a length T4103 for a next non-record part so that the thermal state of a mark ending end is made fixed without depending on the recording pattern. Thereby, both the starting end and the ending end of the mark can be formed in desired positions. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a method and apparatus for recording optical information for optically recording and reproducing.

  Optical discs for recording information using laser beams have already been put to practical use, but higher densities are required. As means for increasing the density, PWM (pulse width modulation) recording in which information is provided at edges of recording marks has been proposed.

FIG. 57 shows a conventional recording method. The laser is driven with the same drive waveform (48b) in response to the recording signal (48a) (for example, see Patent Document 1).
JP-A-5-234079 (all pages, all drawings)

 However, the conventional method has the following problems.

  In the conventional method, the rise and fall of the optical drive waveform (48b) coincide with the rise and fall of the recording signal (48a). However, since the recording light spot 5701 is large, the recording light spot 5701 has a large size. The length W5701 of the irradiation range (48c) is longer than the desired time T5701.

  Therefore, in the formed recording mark (48d), the mark start end is longer than the desired position by d5701, and the mark end is longer than the desired position by d5702.

  Similarly, when recording a recording signal T5702 having a different length, the length of the mark becomes longer by d5703 at the beginning of the mark and by d5704 at the end of the mark. However, the heat history at the beginning of the mark depends on the length of the mark. In particular, d5703 ≠ d5701 because the cooling conditions after the temperature rise are different, and d5704 ≠ d5702 at the end of the mark because the heat accumulation differs depending on the mark length.

Furthermore, in the case of the recording signal T5703 having the same length as T5701, if the interval from the previous mark is different (B5703５７B5701), the influence of the heat exerted by the previous recording power on the current mark starting end is different. If the elongation is different (d5705 ≠ d5701), and if the distance from the next mark is different (A5703 ≠ A5701), the heat history at the end of the mark is different, so the elongation at the end of the mark is different. (D5706 @ d5702)
As described above, the conventional method has a problem that a recording mark having a length different from a desired length is formed, and the amount of the difference varies depending on the length of the mark and the distance between the preceding and following marks.

  The present invention has been made in view of the above problems, and provides an optical information recording method and a recording apparatus for accurately forming a recording mark of a desired length at a desired position.

  In order to solve the above problems, the present invention is configured as follows when recording optical information by forming a large number of recording marks on a recording medium by irradiating light from a light source such as a laser. I do.

  In the first invention, when forming one current recording mark, the driving start time at the recording power of the light source for forming the current recording mark is changed according to the length of the current recording mark. I do.

  As realization means of the first invention, a first measurement means for measuring a current recording signal output period, a delay means for delaying a current recording signal according to a measurement result of the first measurement means, And a driving unit for driving the light source with the recording power from the rising of the recording signal delayed by the delay unit to the falling of the recording signal before the delay.

  In the second invention, when forming one recording mark this time, the light source is driven with the recording power a plurality of times in a time-division manner. At this time, at least the first drive start time of the plurality of drives of the light source is changed according to the length of the current recording mark to be recorded.

  As a means for realizing the second invention, a pulse train signal converting means for converting each one recording signal for recording optical information into a pulse train signal composed of a plurality of pulses, and a second means for measuring a current recording signal output period. A first measuring means, a delay means for delaying at least the first pulse of each pulse included in the pulse train signal obtained by the pulse train signal converting means in accordance with a measurement result of the first measuring means; A driving unit is provided for driving the light source with a recording power based on a pulse train signal including a pulse delayed by the delay unit.

  According to the third aspect of the invention, when forming one recording mark this time, the current recording mark is formed according to the length of the non-recording area immediately before the current recording mark and the length of the current recording mark. The driving start time at the recording power of the light source for forming a mark is changed.

  As a means for realizing the third invention, a first measuring means for measuring a no-signal period sandwiched between a previous one recording signal output for recording optical information and a current recording signal output, A second measuring means for measuring the current recording signal output period; a delay means for delaying the current recording signal in accordance with both the measurement results of the first and second measuring means; And a driving unit for driving the light source with the recording power from the rising of the recording signal to the falling of the recording signal before the delay.

  In the fourth invention, when forming one recording mark this time, the light source is driven with recording power a plurality of times in a time-division manner. At this time, at least the first drive of the plurality of driving of the light source depends on the length of the area of the non-recording portion immediately before the current recording mark and the length of the current recording mark. Change the start time.

  As means for realizing the fourth invention, a pulse train signal converting means for converting each one recording signal for recording optical information into a pulse train signal composed of a plurality of pulses, A first measuring means for measuring a non-signal period sandwiched between output of the recording signal, a second measuring means for measuring a current recording signal output period, and both of the first and second measuring means. A delay unit that delays at least the first pulse of each pulse included in the pulse train signal obtained by the pulse train signal conversion unit according to the measurement result; and a pulse train signal including the pulse delayed by the delay unit. Driving means for driving the light source with recording power.

  In the fifth invention, when one recording mark is formed this time, the length of the area of the non-recording part immediately before the recording mark and the previously formed recording mark positioned so as to sandwich the non-recording part are present. The drive start time at the recording power of the light source for forming the current recording mark is changed in accordance with the power length and the current recording mark length.

  As a means for realizing the fifth invention, a first measuring means for measuring a non-signal period sandwiched between a previous one recording signal output for recording optical information and a current recording signal output, A second measuring means for measuring the output period of the previous recording signal immediately before the no-signal period, a third measuring means for measuring the output period of the current recording signal, and the first, second and third measuring means; A delay unit for delaying the current recording signal in accordance with the measurement result of the measurement unit; and a drive for driving the light source with the recording power from the rising of the recording signal after the delay to the falling of the recording signal before the delay by the delay unit. Means are provided.

  In the sixth invention, when forming one recording mark this time, the light source is driven with the recording power a plurality of times in a time-division manner. Also, at this time, the length of the area of the non-recording part immediately before the current recording mark, the length of the recording mark of the previous formation positioned sandwiching the non-recording part, and the length of the current recording mark At least the first drive start time of the plurality of drives of the light source is changed according to the desired length.

  As a means for realizing the sixth invention, a pulse train signal converting means for converting each one recording signal for recording optical information into a pulse train signal composed of a plurality of pulses, First measuring means for measuring a no-signal period sandwiched between recording signal outputs, second measuring means for measuring a previous recording signal output period immediately before the no-signal period, and A third measuring means for measuring the output period, and, of the pulses included in the pulse train signal obtained by the pulse train signal converting means, according to the measurement results of the first, second, and third measuring means. A delay unit for delaying at least the first pulse and a driving unit for driving the light source with the recording power based on a pulse train signal including the pulse delayed by the delay unit are provided.

  In the seventh invention, when one recording mark is formed this time, the drive end time of the light source for forming the current recording mark is changed according to the length of the recording mark.

  As means for realizing the seventh invention, a first measuring means for measuring the output period of the current recording signal, and a delay means for delaying the current recording signal according to the measurement result of the first measuring means. And a driving unit for driving the light source with the recording power from the rising of the recording signal before the delay to the falling of the recording signal after the delay by the delay unit.

  In the eighth invention, in forming one recording mark at this time, the light source is driven with recording power a plurality of times in a time-division manner. At this time, at least the last drive end time of the plurality of drives of the light source is changed according to the length of the current recording mark.

  As a means for realizing the eighth invention, a pulse train signal converting means for converting each recording signal for recording optical information into a pulse train signal composed of a plurality of pulses, and measuring an output period of the present recording signal. First measuring means, and delay means for delaying at least the last pulse of each pulse included in the pulse train signal obtained by the pulse train signal converting means in accordance with the measurement result of the first measuring means, And a driving unit for driving the light source with recording power based on a pulse train signal including a pulse delayed by the delay unit.

  In the ninth aspect, when forming one recording mark this time, the current recording mark is formed according to the desired length of the current recording mark and the desired length of the non-recording area immediately after the current recording mark. The drive end time at the recording power of the light source for forming a mark is changed.

  As a means for realizing the ninth invention, a first measuring means for measuring the output period of the current recording signal, a second measuring means for measuring a non-signal period immediately after the current recording signal, and the first measuring means A delay unit for delaying the current recording signal in accordance with both measurement results of the second measuring unit, and recording the light source from the rising of the recording signal before the delay to the falling of the recording signal after the delay by the delay unit. And driving means driven by power.

  In the tenth aspect, when forming one recording mark this time, the light source is driven with a recording power a plurality of times in a time-division manner. Also, at this time, at least the last drive of the plurality of drive of the light source depends on the length of the current recording mark and the length of the non-recording area immediately after the current recording mark. Change the end time.

  As a means for realizing the tenth invention, a pulse train signal converting means for converting each recording signal for recording optical information into a pulse train signal composed of a plurality of pulses, and measuring an output period of the present recording signal. A first measuring means, a second measuring means for measuring a no-signal period immediately after the current recording signal, and the pulse train signal converting means in accordance with both measurement results of the first and second measuring means. Delay means for delaying at least the last pulse of each pulse included in the obtained pulse train signal, and drive means for driving the light source with recording power based on the pulse train signal including the pulse delayed by the delay means Are provided.

  In the eleventh invention, when forming one current recording mark, the driving start time at the recording power of the light source for forming the current recording mark is changed according to the length of the current recording mark. In addition, the drive end time at the recording power of the light source for forming the current recording mark is changed according to the length of the current recording mark.

  As means for realizing the eleventh invention, a first measuring means for measuring the output period of the current recording signal, and a first measuring means for delaying the current recording signal in accordance with the measurement result of the first measuring means. A delay unit, a second delay unit that delays a current recording signal in accordance with a measurement result of the first measurement unit, and a second delay unit that delays a rising edge of the recording signal after the delay by the first delay unit. And a driving unit for driving the light source with the recording power until the fall of the recording signal after the delay by the delay unit.

  In the twelfth aspect, when forming one recording mark this time, the light source is driven with recording power a plurality of times in a time-division manner. At this time, at least the first drive start time of the multiple driving of the light source is changed according to the length of the current recording mark, and the length of the current recording mark is changed to the desired length. Accordingly, at least the last drive end time of the plurality of drives of the light source is changed.

  As a means for realizing the twelfth aspect, a pulse train signal converting means for converting each recording signal for recording optical information into a pulse train signal composed of a plurality of pulses, and measuring an output period of the present recording signal. First measuring means, and first delay means for delaying at least the first pulse of each pulse included in the pulse train signal obtained by the pulse train signal converting means in accordance with the measurement result of the first measuring means. And second delay means for delaying at least the last pulse of each pulse included in the pulse train signal obtained by the pulse train signal conversion means in accordance with the measurement result of the first measurement means; Driving means for driving the light source with recording power based on a pulse train signal including a pulse delayed by the second delay means.

  In the thirteenth invention, when forming one recording mark this time, the drive start time at the recording power of the light source for forming the current recording mark is changed according to the length of the current recording mark. And the recording power of the light source for forming the current recording mark in accordance with the length of the current recording mark and the length of the non-recording area immediately after the current recording mark. To change the drive end time.

  As means for realizing the thirteenth invention, a first measuring means for measuring the output period of the current recording signal, a second measuring means for measuring a non-signal period immediately after the current recording signal, A first delay means for delaying the current recording signal in accordance with the measurement result of the measuring means, and a second delay means for delaying the current recording signal in accordance with the measurement results of the first and second measuring means. And driving means for driving the light source with the recording power from the rise of the recording signal after the delay by the first delay means to the fall of the recording signal after the delay by the second delay means.

  In the fourteenth invention, when forming one recording mark this time, the light source is driven with a recording power a plurality of times in a time-division manner. Also, at this time, according to the length of the current recording mark, at least the first drive start time of the multiple driving of the light source is changed, and the length of the current recording mark and At least the last drive end time of the plurality of drive operations of the light source is changed according to the length of the non-recording area immediately after the current recording mark.

  As a means for realizing the fourteenth invention, a pulse train signal converting means for converting each recording signal for recording optical information into a pulse train signal composed of a plurality of pulses, and measuring an output period of the present recording signal. A first measuring means, a second measuring means for measuring a no-signal period immediately after the current recording signal, and a pulse train signal obtained by the pulse train signal converting means in accordance with a measurement result of the first measuring means. First delay means for delaying at least the first pulse of each pulse included in the pulse train signal, and a pulse train signal obtained by the pulse train signal converting means according to the measurement results of the first and second measuring means. A second delay unit for delaying at least the last pulse of each of the included pulses; and recording the light source based on a pulse train signal including the pulses delayed by the first and second delay units. Providing driving means for driving at word.

  In the fifteenth aspect, when forming one recording mark this time, the current recording mark is formed according to the desired length of the non-recording area immediately before the current recording mark and the desired length of the current recording mark. The drive start time at the recording power of the light source for forming a mark is changed, and the recording power of the light source for forming the current recording mark is changed according to the length of the current recording mark. To change the drive end time.

  As a means for realizing the fifteenth invention, a first measuring means for measuring a no-signal period between a previous recording signal output and a current recording signal output, and a current recording signal output period Second measuring means for measuring, first delay means for delaying the current recording signal in accordance with both measurement results of the first and second measuring means, and measurement result of the second measuring means. A second delay unit for delaying the current recording signal, and the light source from a rising edge of the recording signal after the delay by the first delay unit to a falling edge of the recording signal after the delay by the second delay unit. And driving means for driving the recording medium with recording power.

  In the sixteenth aspect, when forming one recording mark this time, the light source is driven with a recording power a plurality of times in a time-division manner. At this time, at least the first drive of the plurality of driving of the light source depends on the length of the area of the non-recording portion immediately before the current recording mark and the length of the current recording mark. The start time is changed, and at least the last drive end time of the plurality of drives of the light source is changed according to the length of the current recording mark.

  As a means for realizing the sixteenth invention, a pulse train signal converting means for converting each one recording signal for recording optical information into a pulse train signal composed of a plurality of pulses, and a current recording signal from a previous recording signal output A first measuring means for measuring a no-signal period sandwiched before output, a second measuring means for measuring an output period of the present recording signal, and both of the first and second measuring means. A first delay unit that delays at least the first pulse of each pulse included in the pulse train signal obtained by the pulse train signal conversion unit according to the measurement result; and a measurement result of the second measurement unit according to the measurement result. A second delay means for delaying at least the last pulse of each pulse included in the pulse train signal obtained by the pulse train signal conversion means, and a pulse delayed by the first and second delay means. Based on the no-pulse train signal, providing a driving means for driving the light source at the recording power.

  In the seventeenth invention, when forming one recording mark of the present time, the current recording mark is formed according to the length of the area of the non-recording portion immediately before the current recording mark and the length of the current recording mark. The drive start time at the recording power of the light source for forming a mark is changed, and the length of the current recording mark and the length of the non-recording area immediately after the current recording mark are changed to the desired length. Accordingly, the drive end time at the recording power of the light source for forming the current recording mark is changed.

  As a means for realizing the seventeenth invention, a first measuring means for measuring a no-signal period between a previous recording signal output and a current recording signal output, and a current recording signal output period Second measuring means for measuring, third measuring means for measuring a no-signal period between the current recording signal output and the next recording signal output, and the first and second measuring means The first delay means for delaying the current recording signal in accordance with the two measurement results, and the second delay means for delaying the current recording signal in accordance with both the measurement results of the second and third measurement means Means, and driving means for driving the light source with the recording power from the rise of the recording signal after the delay by the first delay means to the fall of the recording signal after the delay by the second delay means.

  In the eighteenth aspect, when forming one recording mark this time, the light source is driven with recording power a plurality of times in a time-division manner. At this time, at least the first drive of the plurality of driving of the light source depends on the length of the area of the non-recording portion immediately before the current recording mark and the length of the current recording mark. The start time is changed, and at least the last driving of the plurality of driving of the light source is performed according to the length of the current recording mark and the length of the non-recording area immediately after the current recording mark. Change the end time.

  As means for realizing the eighteenth aspect of the present invention, there is provided a pulse train signal converting means for converting each recording signal for recording optical information into a pulse train signal composed of a plurality of pulses; First measuring means for measuring a no-signal period sandwiched before output, second measuring means for measuring an output period of a current recording signal, and a next recording signal output from a current recording signal output A third measuring means for measuring a non-signal period between the first and second measuring means, and a pulse train signal obtained by the pulse train signal converting means in accordance with both measurement results of the first and second measuring means. The pulse train signal included in the pulse train signal obtained by the pulse train signal converting means according to both measurement results of the first delay means for delaying at least the first pulse of the included pulses and the second and third measuring means. Each pal Second delay means for delaying at least the last pulse of the above, and drive means for driving the light source with recording power based on a pulse train signal including the pulse delayed by the first and second delay means. Is provided.

  In the nineteenth aspect, the recording waveform for forming a recording mark corresponding to the inversion interval T of the modulated data is the first pulse and (T−Tmin) / Tw pulses (Tmin is the minimum inversion interval, Tw). Is a detection window width), the interval between the rise of the modulation data and the rise of the first pulse is x (0 <x), and the rise of the modulation data is When the interval from the falling edge of the first pulse is Tmin + y (y <0.5 Tw), x is set so that the mark of the maximum inversion interval is formed to a desired length. Is set so that the mark is formed to a desired length.

  As means for realizing the nineteenth invention, a clock generator for generating a clock having a period of a detection window width, a modulator for modulating input data, and a pulse generator for outputting a pulse at a minimum inversion interval from the output of the modulator A first delay circuit that outputs a pulse obtained by delaying a rising edge of an output pulse of the pulse generation circuit; and a second circuit that outputs a pulse obtained by delaying a falling edge of an output pulse of the first delay circuit. 2 delay circuit, a multi-pulse generation circuit that outputs a plurality of pulse trains using the output of the modulator, the output of the pulse generation circuit, and the clock, the output of the second delay circuit, and the multi-pulse generation circuit OR circuit for outputting a logical sum of the output of the OR circuit, a laser drive circuit for driving the laser of the optical head using the output of the OR circuit, and the laser drive circuit Accordingly, and an optical head for recording signals on an optical disc having a recordable area.

  According to the first invention, when forming the current recording mark, the start time of light irradiation when forming the current recording mark is changed according to the length of the current recording mark. As a result, it is possible to correct the difference in the thermal history at the mark start end portion due to the length of the recording mark, so that the start end portion of the record mark can be formed at a correct position.

  In the second aspect of the invention, since the light source such as a laser emits a pulse light, when forming the current recording mark, the thermal effect at the time of forming the previous recording mark is reduced, and the current recording mark should be present. The start time of at least the first pulse in the pulse emission for forming the current recording mark is changed according to the length. As a result, it is possible to correct the difference in the thermal history at the mark start end portion due to the length of the recording mark, so that the start end portion of the record mark can be formed at a correct position.

  In the third invention, when forming the current recording mark, the current recording mark is formed in accordance with the length of the non-recording portion immediately before the current recording mark and the length of the current recording mark. In this case, the start time of light irradiation is changed. As a result, it is possible to correct the influence of the heat at the time of forming the previous recording mark on the starting end of the current recording mark, and to correct the difference in the heat history at the mark starting end depending on the length of the current recording mark. It is possible to form the starting end of the current recording mark at the correct position.

  In the fourth aspect, since the light source such as a laser emits pulse light, when forming the current recording mark, the thermal effect of forming the previous recording mark is reduced, and the recording mark immediately before the current recording mark is formed. The start time of at least the first pulse in the pulse emission for forming the current recording mark is changed according to the desired length of the unrecorded portion area and the desired length of the current recording mark. As a result, it is possible to correct the influence of the heat at the time of forming the previous recording mark on the starting end of the current recording mark, and to correct the difference in the heat history at the mark starting end depending on the length of the current recording mark. It is possible to form the starting end of the current recording mark at the correct position.

  In the fifth invention, when forming the current recording mark, the length of the non-recording area immediately before the current recording mark, the length of the previous recording mark, and the present recording mark should be present. The start time of light irradiation for forming the current recording mark is changed according to the length. As a result, it is possible to correct the influence of the heat at the time of forming the previous recording mark on the starting end of the current recording mark, and to correct the difference in the heat history at the mark starting end depending on the length of the current recording mark. It is possible to form the starting end of the current recording mark at the correct position.

  According to the sixth aspect, since the light source such as a laser emits a pulse, when forming the current recording mark, the thermal effect when the previous recording mark is formed is reduced, and the recording mark immediately before the current recording mark is formed. At least the first pulse in the pulse emission for forming the current recording mark according to the desired length of the area of the non-recording portion, the desired length of the previous recording mark, and the desired length of the current recording mark Start time is changed. As a result, it is possible to correct the influence of the heat at the time of forming the previous recording mark on the starting end of the current recording mark, and to correct the difference in the heat history at the mark starting end depending on the length of the current recording mark. It is possible to form the starting end of the current recording mark at the correct position.

  According to the seventh aspect, when forming the current recording mark, the end time of light irradiation when forming the current recording mark is changed according to the length of the recording mark. As a result, it is possible to correct the difference in heat accumulation at the end of the mark due to the length of the recording mark, so that the end of the current recording mark can be formed at the correct position.

  In the eighth invention, since a light source such as a laser emits a pulse, when forming the current recording mark, the thermal effect when the previous recording mark was formed is reduced, and the present recording mark should be present. The end time of at least the last pulse in the pulse emission for forming the current recording mark is changed according to the length. As a result, it is possible to correct the difference in heat accumulation at the end of the mark due to the length of the recording mark, so that the end of the current recording mark can be formed at a correct position.

  According to the ninth aspect, when the current recording mark is formed, the current recording mark is determined according to the length of the current recording mark and the length of the non-recording area immediately after the current recording mark. The end time of the light irradiation when forming is changed. As a result, the difference in heat accumulation at the mark end due to the length of the recording mark and the difference in heat history at the mark end due to the distance to the next recording mark can be corrected. It becomes possible to form parts.

  In the tenth aspect, since the light source such as a laser emits a pulse light, when forming the current recording mark, the thermal effect when the previous recording mark was formed is reduced, and the present recording mark should be present. The end time of at least the last pulse in the pulse emission for forming the current recording mark is changed according to the length and the desired length of the non-recording area immediately after the current recording mark. As a result, the difference in heat accumulation at the mark end due to the length of the recording mark and the difference in heat history at the mark end due to the distance to the next recording mark can be corrected. It becomes possible to form parts.

  In the eleventh invention, when forming the current recording mark, the start time of light irradiation when forming the current recording mark is changed according to the length of the current recording mark, and The end time of light irradiation for forming the current recording mark is changed according to the length of the recording mark. As a result, it is possible to correct the difference in thermal history at the mark start end portion due to the length of the recording mark, and to correct the difference in heat accumulation at the mark end portion due to the length of the recording mark. The start and end portions can be formed.

  According to the twelfth aspect, since the light source such as a laser emits pulse light, when forming the current recording mark, the thermal effect when the previous recording mark was formed is reduced, and the present recording mark should be present. The start time of at least the first pulse in the pulse emission for forming the current recording mark is changed according to the length, and the current recording mark is formed according to the length of the current recording mark. In this case, the end time of at least the last pulse in the pulse emission is changed. As a result, it is possible to correct the difference in heat history at the mark start end portion due to the length of the recording mark, and to correct the difference in heat accumulation at the mark end portion due to the length of the recording mark. The start and end portions can be formed.

  In the thirteenth invention, when forming the current recording mark, the start time of light irradiation when forming the current recording mark is changed according to the length of the current recording mark, and The end time of light irradiation when forming the current recording mark is changed according to the length of the recording mark and the length of the non-recording area immediately after the current recording mark. As a result, it is possible to correct the difference in the thermal history at the mark start end portion due to the length of the recording mark, and to correct the difference in the heat accumulation at the mark end portion due to the length of the recording mark, and the distance from the next recording mark. Can correct the difference in the thermal history at the mark end portion, so that the start and end portions of the current recording mark can be formed at the correct positions.

  According to the fourteenth aspect, the light source such as a laser emits a pulse, so that when forming the current recording mark, the thermal effect when the previous recording mark was formed is reduced, and the present recording mark should be present. The start time of at least the first pulse in pulse emission for forming the current recording mark is changed according to the length, and the length of the current recording mark and the non-recording immediately after the current recording mark are changed. The end time of at least the last pulse in the pulse emission for forming the current recording mark is changed according to the desired length of the partial area. As a result, it is possible to correct the difference in the thermal history at the mark start end portion due to the length of the recording mark, and to correct the difference in the heat accumulation at the mark end portion due to the length of the recording mark, and the distance from the next recording mark. Can correct the difference in the thermal history at the mark end portion, so that the start and end portions of the current recording mark can be formed at the correct positions.

  In the fifteenth aspect, when forming the current recording mark, the current recording mark is determined according to the length of the non-recording area immediately before the current recording mark and the length of the current recording mark. Is changed, and the end time of the light irradiation for forming the current recording mark is changed according to the length of the current recording mark. As a result, it is possible to correct the thermal effect on the starting end of the current recording mark due to the formation of the previous recording mark, and to correct the difference in the thermal history of the mark starting end due to the length of the recording mark, and Since the difference in heat accumulation at the end of the mark due to the length of the mark can be corrected, the start and end of the current recording mark can be formed at the correct positions.

  In the sixteenth aspect, a light source such as a laser emits pulse light, so that when forming the current recording mark, the thermal effect when forming the recording mark immediately before the recording mark is reduced, and The start time of at least the first pulse in the pulse emission for forming the current recording mark depends on the length of the area of the non-recording portion immediately before the recording mark and the length of the current recording mark. The end time of at least the last pulse in the pulse emission for forming the current recording mark is changed according to the length of the current recording mark that has been changed. As a result, it is possible to correct the thermal effect on the starting end of the current recording mark due to the formation of the previous recording mark, and to correct the difference in the thermal history of the mark starting end due to the length of the recording mark, and Since the difference in heat accumulation at the end of the mark due to the length of the mark can be corrected, the start and end of the current recording mark can be formed at the correct positions.

  In the seventeenth invention, when the current recording mark is formed, the current recording mark is determined according to the length of the non-recording area immediately before the current recording mark and the length of the current recording mark. The start time of the light irradiation when forming is changed, and the current recording time is changed according to the desired length of the current recording mark and the desired length of the non-recording area immediately after the current recording mark. The end time of light irradiation for forming a mark is changed. As a result, it is possible to correct the thermal effect on the starting end of the current recording mark due to the formation of the previous recording mark, and to correct the difference in the thermal history of the mark starting end due to the length of the recording mark, and The difference in heat accumulation at the end of the mark due to the length of the mark can be corrected, and the difference in heat history at the end of the mark due to the distance to the next mark can be corrected. It becomes possible to form parts.

  In the eighteenth aspect, the light source such as a laser emits a pulse, so that when forming the current recording mark, the thermal effect of forming the recording mark immediately before the recording mark is reduced, and The start time of at least the first pulse in the pulse emission for forming the current recording mark depends on the length of the area of the non-recording portion immediately before the recording mark and the length of the current recording mark. At least the last in the pulse emission for forming the current recording mark is changed, and according to the desired length of the current recording mark and the desired length of the non-recording area immediately after the current recording mark. Is changed. As a result, it is possible to correct the thermal effect on the starting end of the current recording mark due to the formation of the previous recording mark, and to correct the difference in the thermal history of the mark starting end due to the length of the recording mark, and The difference in heat accumulation at the end of the mark due to the length of the mark can be corrected, and the difference in heat history at the end of the mark due to the distance to the next mark can be corrected. It becomes possible to form parts.

  According to the nineteenth aspect, the recording mark corresponding to the maximum inversion interval can be formed to a desired length by delaying the rising edge of the first pulse, and the recording mark can be minimized by delaying the falling edge of the first pulse. A recording mark corresponding to the reversal interval can be formed to a desired length.

  In the first invention, when forming the current recording mark, the start time of light irradiation when forming the current recording mark is changed according to the length of this recording mark. As a result, it is possible to correct the difference in the thermal history at the start end portion due to the length of the recording mark, and to form the start end portion of the current recording mark at a correct position.

  In the second aspect of the invention, since the light source such as a laser emits a pulse, when forming the current recording mark, the thermal effect when forming the recording mark immediately before the recording mark is reduced, and The start time of at least the first pulse in the pulse emission for forming the current recording mark is changed according to the desired length of the recording mark. As a result, it is possible to correct the difference in the thermal history at the start end portion due to the length of the current recording mark, so that the start end portion of the current recording mark can be formed at a correct position. Further, the pulsed light emission has an effect of reducing the heat load applied to the medium and reducing deterioration due to repeated recording.

  In the third invention, when the current recording mark is formed, the current recording mark is formed according to the length of the non-recording area immediately before the recording mark and the length of the current recording mark. The start time of light irradiation when forming is changed. As a result, it is possible to correct the influence of the heat at the time of forming the immediately preceding recording mark on the starting end of the current recording mark, and to correct the difference in the heat history at the mark starting end due to the length of the current recording mark. Therefore, it is possible to form the start end of the current recording mark at the correct position.

  According to the fourth aspect, since the light source such as a laser emits a pulse, when forming the current recording mark, the thermal effect at the time of forming the recording mark immediately before the recording mark is reduced, and The start time of at least the first pulse in the pulse emission for forming the current recording mark is changed according to the desired length of the non-recording area immediately before the recording mark and the desired length of the current recording mark. Is done. As a result, it is possible to correct the influence of the heat at the time of forming the immediately preceding recording mark on the starting end of the current recording mark, and to correct the difference in the heat history at the mark starting end due to the length of the current recording mark. Therefore, it is possible to form the start end of the current recording mark at the correct position. Further, the pulsed light emission has an effect of reducing the heat load applied to the medium and reducing deterioration due to repeated recording.

  In the fifth invention, when the current recording mark is formed, the length of the area of the non-recording part immediately before the recording mark and the immediately preceding recording mark positioned so as to sandwich the non-recording part are present. The start time of light irradiation when forming the current recording mark is changed according to the power length and the desired length of the current recording mark. As a result, it is possible to correct the influence of the heat at the time of forming the immediately preceding recording mark on the starting end of the current recording mark, and to correct the difference in the heat history at the mark starting end due to the length of the current recording mark. Therefore, it is possible to form the start end of the current recording mark at the correct position.

  In the sixth invention, since the light source such as a laser emits a pulse, when forming the current recording mark, the thermal effect when forming the recording mark immediately before the recording mark is reduced, and According to the length of the area of the non-recording part immediately before the recording mark and the length of the immediately preceding recording mark and the length of the current recording mark sandwiching the non-recording part. The start time of at least the first pulse in the pulse emission for forming the current recording mark is changed. As a result, it is possible to correct the influence of the heat at the time of forming the immediately preceding recording mark on the starting end of the current recording mark, and to correct the difference in the heat history at the mark starting end due to the length of the current recording mark. Therefore, it is possible to form the start end of the current recording mark at the correct position. Further, the pulsed light emission has an effect of reducing the heat load applied to the medium and reducing deterioration due to repeated recording.

  According to the seventh aspect, when forming the current recording mark, the end time of light irradiation when forming the current recording mark is changed according to the length of the recording mark. As a result, it is possible to correct the difference in heat accumulation at the end of the mark due to the length of the recording mark, so that the end of the current recording mark can be formed at the correct position.

  In the eighth invention, since a light source such as a laser emits pulse light, when forming the current recording mark, the thermal effect at the time of forming the recording mark immediately before the recording mark is reduced, and The end time of at least the last pulse in the pulse emission for forming the current recording mark is changed according to the desired length of the recording mark. As a result, it is possible to correct the difference in heat accumulation at the end of the mark due to the length of the recording mark, so that the end of the current recording mark can be formed at a correct position. Further, the pulsed light emission has an effect of reducing the heat load applied to the medium and reducing deterioration due to repeated recording.

  According to the ninth aspect, when the current recording mark is formed, the current recording mark is determined according to the length of the current recording mark and the length of the non-recording area immediately after the current recording mark. The end time of the light irradiation when forming is changed. As a result, the difference in heat accumulation at the mark end due to the length of the recording mark and the difference in heat history at the mark end due to the distance to the next recording mark can be corrected. It becomes possible to form parts.

  According to the tenth aspect, since the light source such as a laser emits a pulse, when forming the current recording mark, the thermal effect at the time of forming the recording mark immediately before the recording mark is reduced, and The end time of at least the last pulse in the pulse emission for forming the current recording mark is determined according to the desired length of the recording mark and the desired length of the non-recording area immediately after the current recording mark. Be changed. As a result, the difference in heat accumulation at the mark end due to the length of the recording mark and the difference in heat history at the mark end due to the distance to the next recording mark can be corrected. It becomes possible to form parts.

  Further, the pulsed light emission has an effect of reducing the heat load applied to the medium and reducing deterioration due to repeated recording.

  In the eleventh invention, when forming the current recording mark, the start time of light irradiation when forming the current recording mark is changed according to the length of the current recording mark, and The end time of light irradiation for forming the current recording mark is changed according to the length of the recording mark. As a result, it is possible to correct the difference in thermal history at the mark start end portion due to the length of the recording mark, and to correct the difference in heat accumulation at the mark end portion due to the length of the recording mark. The start and end portions can be formed.

  In the twelfth aspect, since the light source such as a laser emits pulse light, the thermal effect of forming the recording mark immediately before the current recording mark is reduced when the current recording mark is formed. The start time of at least the first pulse in the pulse emission for forming the current recording mark is changed according to the length of the recording mark, and according to the length of the current recording mark, The end time of at least the last pulse in the pulse emission for forming the current recording mark is changed. As a result, it is possible to correct the difference in heat history at the mark start end portion due to the length of the recording mark, and to correct the difference in heat accumulation at the mark end portion due to the length of the recording mark. The start and end portions can be formed.

  Further, the pulsed light emission has an effect of reducing the heat load applied to the medium and reducing deterioration due to repeated recording.

  In the thirteenth invention, when forming the current recording mark, the start time of light irradiation when forming the current recording mark is changed according to the length of the current recording mark, and The end time of light irradiation when forming the current recording mark is changed according to the length of the recording mark and the length of the non-recording area immediately after the current recording mark. As a result, it is possible to correct the difference in the thermal history at the mark start end portion due to the length of the recording mark, and to correct the difference in the heat accumulation at the mark end portion due to the length of the recording mark, and the distance from the next recording mark. Can correct the difference in the thermal history at the mark end portion, so that the start and end portions of the current recording mark can be formed at the correct positions.

  According to the fourteenth aspect, the light source such as a laser emits a pulse, so that when forming the current recording mark, the thermal effect of forming the recording mark immediately before the recording mark is reduced, and The start time of at least the first pulse in the pulse emission for forming the current recording mark is changed according to the length of the current recording mark, and the length of the current recording mark and the current recording The end time of at least the last pulse in the pulse emission for forming the current recording mark is changed according to the length of the non-recording area immediately after the mark. As a result, it is possible to correct the difference in the thermal history at the mark start end portion due to the length of the recording mark, and to correct the difference in the heat accumulation at the mark end portion due to the length of the recording mark, and the distance from the next recording mark. Can correct the difference in the thermal history at the mark end portion, so that the start and end portions of the current recording mark can be formed at the correct positions.

  Further, the pulsed light emission has an effect of reducing the heat load applied to the medium and reducing deterioration due to repeated recording.

  In the fifteenth aspect, when forming the current recording mark, the current recording mark is determined according to the length of the non-recording area immediately before the current recording mark and the length of the current recording mark. Is changed, and the end time of the light irradiation for forming the current recording mark is changed according to the length of the current recording mark. As a result, it is possible to correct the thermal effect on the starting end of the current recording mark due to the formation of the previous recording mark, and to correct the difference in the thermal history of the mark starting end due to the length of the recording mark, and Since the difference in heat accumulation at the end of the mark due to the length of the mark can be corrected, the start and end of the current recording mark can be formed at the correct positions.

  In the sixteenth aspect, a light source such as a laser emits pulse light, so that when forming the current recording mark, the thermal effect when forming the recording mark immediately before the recording mark is reduced, and The start time of at least the first pulse in the pulse emission for forming the current recording mark depends on the length of the area of the non-recording portion immediately before the recording mark and the length of the current recording mark. The end time of at least the last pulse in the pulse emission for forming the current recording mark is changed according to the length of the current recording mark that has been changed. As a result, it is possible to correct the thermal effect on the starting end of the current recording mark due to the formation of the previous recording mark, and to correct the difference in the thermal history of the mark starting end due to the length of the recording mark, and Since the difference in heat accumulation at the end of the mark due to the length of the mark can be corrected, the start and end of the current recording mark can be formed at the correct positions.

  Further, the pulsed light emission has an effect of reducing the heat load applied to the medium and reducing deterioration due to repeated recording.

  In the seventeenth invention, when the current recording mark is formed, the current recording mark is determined according to the length of the non-recording area immediately before the current recording mark and the length of the current recording mark. The start time of the light irradiation when forming is changed, and the current recording time is changed according to the desired length of the current recording mark and the desired length of the non-recording area immediately after the current recording mark. The end time of light irradiation for forming a mark is changed. As a result, it is possible to correct the thermal effect on the starting end of the current recording mark due to the formation of the previous recording mark, and to correct the difference in the thermal history of the mark starting end due to the length of the recording mark, and The difference in heat accumulation at the end of the mark due to the length of the mark can be corrected, and the difference in heat history at the end of the mark due to the distance to the next mark can be corrected. It becomes possible to form parts.

  In the eighteenth aspect, the light source such as a laser emits a pulse, so that when forming the current recording mark, the thermal effect of forming the recording mark immediately before the recording mark is reduced, and The start time of at least the first pulse in the pulse emission for forming the current recording mark depends on the length of the area of the non-recording portion immediately before the recording mark and the length of the current recording mark. At least the last in the pulse emission for forming the current recording mark is changed, and according to the desired length of the current recording mark and the desired length of the non-recording area immediately after the current recording mark. Is changed. As a result, it is possible to correct the thermal effect on the starting end of the current recording mark due to the formation of the previous recording mark, and to correct the difference in the thermal history of the mark starting end due to the length of the recording mark, and The difference in heat accumulation at the end of the mark due to the length of the mark can be corrected, and the difference in heat history at the end of the mark due to the distance to the next mark can be corrected. It becomes possible to form parts.

  Further, the pulsed light emission has an effect of reducing the heat load applied to the medium and reducing deterioration due to repeated recording.

  According to the nineteenth aspect, the length of the recording mark corresponding to the maximum inversion interval and the minimum inversion interval can be set to a desired value.

  Further, the pulsed light emission has an effect of reducing the heat load applied to the medium and reducing deterioration due to repeated recording.

(Example 1)
An optical drive waveform 116 in FIG. 2 is an optical drive waveform in the first embodiment of the present invention.

  The drive start time of the optical drive waveform 116 is delayed with respect to the recording signal 106.

  The delay amount is determined according to the length of the recording mark as shown in Table 1 in the case of (1, 7) modulation.

  For example, since the desired length of the recording mark 201 is T201 = 2Tw (Tw is the detection window width), it is delayed by d1 (2), and the desired length of the recording mark 202 is T202 = 8Tw. Delay by (8).

  The shorter the recording mark length, the easier it is to obtain the quenching condition at the beginning of the mark.Therefore, when using a phase change medium that forms an amorphous mark by quenching after heating, the shorter the mark, the longer the elongation at the beginning. large. Therefore, there is a relationship d1 (2)> d2 (3) >>...> D1 (8).

  As a result, it is possible to correct a difference in the thermal history of the mark start end portion due to the recording mark length, and the start end portions of the recording marks 201 and 202 are formed at correct positions.

  Although the optical driving waveform 116 is driven between the recording power and the erasing power here, if the driving is performed in accordance with the recording medium, for example, between the recording power and the reproducing power, or between the recording power and 0. Good.

  FIG. 1 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to a first embodiment of the present invention.

  In FIG. 1, 101 is a clock generation circuit, 102 is a channel clock signal, 103 is a recording signal generation circuit, 104 is a recording signal output from the recording signal generation circuit 103, 105 is an H level period length measuring circuit, and 106 is an H level period The recording signal after passing through the length measuring circuit 105, 107 is an H level period measurement result output, and 108 is a delay circuit, which comprises a memory 109 and a variable delay unit 111. 112 is a delay circuit output, 113 is an AND circuit, 114 is its output, 115 is a laser drive circuit, and 116 is an optical drive waveform.

  The operation of the above configuration will be described with reference to the timing chart of FIG.

  The clock generation circuit 101 outputs a channel clock 102 having a cycle of the detection window width Tw. The duty is variable.

  The recording signal 104 output from the recording signal generating circuit 103 is input to the H-level period length measuring circuit 105 in synchronization with the rise of the channel clock signal 102 from the clock generating circuit 101. The H level period length measuring circuit 105 measures the length of the H level period of the recording signal 104, and outputs the recording signal 106 and the measurement result 107 again. The measurement result 107 is output at the rising of the measured H level of the recording signal 106. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T201 is 2, and the measurement result 107 becomes 2 at the rise of T201. The length of the H level period T202 is 8, and the measurement result 107 becomes 8 at the rise of T202.

  Then, the measurement result 107 is input to the delay circuit 108.

  In the delay circuit 108, the measurement result 107 is input to a memory 109, and a memory output 110 is output from the memory 109. Here, as shown in Table 1, a value corresponding to the mark length to be recorded is stored in the memory 109, and a stored value corresponding to the measurement result 107 is output.

  The variable delay unit 111 outputs the signal 112 by delaying the recording signal 106 according to the memory output 110.

  The recording signal 106 and the signal 112 are input to an AND circuit 113 and output as a signal 114.

  The output signal 114 is input to the laser drive circuit 115, and the light source is driven to form an optical drive waveform 116, and the recording marks 201 and 202 are formed.

  As described above, in the first embodiment, when the recording mark 201 or 202 is formed, the driving start time at the recording power of the light source is delayed according to the recording length of the recording mark. The difference in the thermal history of the mark start end can be corrected, and the start end of the recording mark can be formed at a correct position.

Here, the optical drive waveform is driven between the recording power and the erasing power, but it may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 2)
An optical drive waveform 323 in FIG. 4 is an optical drive waveform according to the second embodiment of the present invention.

  The optical drive waveform 323 is composed of a plurality of pulses of a leading pulse and a multi-pulse. Further, the start time of the leading pulse of the optical drive waveform 323 is delayed with respect to the recording signal 306.

  The delay amount is determined according to the length of the recording mark as shown in Table 2 in the case of (1, 7) modulation.

  For example, the desired length of the recording mark 401 is T401 = 2Tw (Tw is the detection window width), so it is delayed by d2 (2), and the desired length of the recording mark 402 is T402 = 8Tw, so only d2 (8) Delay.

  The shorter the length of the mark to be recorded, the easier it is to obtain the quenching condition at the start of the mark. Large growth. Therefore, there is a relationship of d2 (2)> d2 (3) >>...> D2 (8).

  As a result, it is possible to correct the difference in the thermal history of the mark start end portion due to the recording mark length, and the start end portions of the recording marks 401 and 402 are formed at correct positions.

  Here, the optical driving waveform is driven between the recording power and the erasing power, but the driving may be performed in accordance with the recording medium, such as between the recording power and the reproducing power, between the recording power and 0, and the like.

  FIG. 3 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to a second embodiment of the present invention.

  3, reference numeral 301 denotes a clock generation circuit, 302 denotes a channel clock signal, 303 denotes a recording signal generation circuit, 304 denotes a recording signal output from the recording signal generation circuit 303, 305 denotes an H level period length measuring circuit, and 306 denotes an H level period. The recording signal after passing through the length measurement circuit 305, 307 is an H level period length measurement result output, 308 is a delay circuit, 309 is a memory, 310 is a memory output, 311 is a variable delay device, 312 is a pulse division circuit, and 313 is a head. The pulse signal 314 is a second-half pulse signal, and 315 is a multi-pulse generation circuit. 318 is a multi-pulse signal, 319 is an output of the delay circuit 308, 320 is an OR circuit, 321 is its output signal, 322 is a laser drive circuit, and 323 is an optical drive waveform.

  The operation of the above configuration will be described with reference to the timing chart of FIG.

  The clock generation circuit 301 outputs a clock 302 whose cycle is the detection window width Tw. The duty is variable.

  The recording signal 304 output from the recording signal generating circuit 303 is input to the H-level period length measuring circuit 305 in synchronization with the rise of the channel clock signal 302 from the clock generating circuit 301. The H level period length measurement circuit 305 measures the length of the H level period of the recording signal 304, and outputs the recording signal 306 and the measurement result 307 again. The measurement result 307 is output at the rising of the measured H level of the recording signal 306. That is, if the length of the H level period is represented by the number of channel clocks, the length of the H level period T401 is 2, and the measurement result 307 becomes 2 at the rise of T401. The length of the H level period T402 is 8, and the measurement result 307 becomes 8 at the rise of T402.

  Then, the measurement result 307 is input to the delay circuit 308.

  In the delay circuit 308, the measurement result 307 is input to the memory 309, and the memory output 309 is output from the memory 309. Here, as shown in Table 2, the memory 309 stores a value corresponding to the length of the recording mark, and outputs a stored value corresponding to the measurement result 307.

  The memory output 310 is input to the variable delay 311.

  On the other hand, the recording signal 306 output from the H-level period length measurement circuit 305 is input to the pulse division circuit 312, and is divided into a first pulse signal 313 and a second pulse signal 314.

  The first pulse 313 is a signal that rises at the rise of the recording signal 306 and falls after Tw.

  The latter half pulse 314 is a signal that rises Tw after the rise of the recording signal 306 and falls at the fall of the recording signal 306.

  The leading pulse signal 313 is input to the delay unit 311, delayed and output as a signal 319.

  The second half pulse signal 314 is input to the multi-pulse generation circuit 315 and output as a multi-pulse 318.

  The signal 319 and the multipulse 318 are added by the OR circuit 320 and output as a signal 321.

  The signal 321 is input to the laser drive circuit 322 and becomes an optical drive waveform 323, and the recording marks 401 and 402 are formed.

As described above, in the second embodiment, when forming the recording marks 401 and 402, the light source emits the pulse light a plurality of times, and according to the length of the recording mark, the first of the plurality of the pulse light emission is performed. Since the time of the pulse emission is delayed, the difference in the thermal history at the mark start end due to the length of the recording mark can be corrected, and the start end of the recording mark can be formed at the correct position. In addition, since light is emitted in a pulsed manner, the heat load applied to the medium is reduced, and there is an effect that deterioration due to repeated recording is reduced.
(Example 3)
An optical drive waveform 518 in FIG. 6 is an optical drive waveform according to the third embodiment of the present invention.

  The drive start time of the optical drive waveform 518 is delayed with respect to the recording signal 508.

  As shown in Table 3, taking the (1,7) modulation as an example, the delay amount corresponds to the combination of the length of the current recording mark and the length of the non-recording portion immediately before it. I can decide.

  For example, the desired length of the mark 601 is T602 = 5Tw (Tw is the detection window width), and the immediately preceding non-recording period is T601 = 2Tw. Therefore, the optical drive waveform is delayed by d3 (2,5), The desired length of the mark 602 is T604 = 8Tw, and the immediately preceding non-recording period is T603 = 6Tw, so that the optical drive waveform is delayed by d3 (6,8).

  If the length of the mark to be recorded is the same, the shorter the desired length of the immediately preceding non-recorded portion, the greater the thermal effect of the previous recording power, and the more likely the temperature to rise at the start of the mark, thus increasing the extension of the start end. . Therefore, there is a relationship of d3 (2, N)> d3 (3, N) >>...> D3 (8, N) (N is an integer of 2 to 8).

  If the length of the previous unrecorded portion is the same, the shorter the mark length to be recorded this time, the easier the quenching condition at the mark start end is. When a phase-change medium for forming a mark is used, the shorter the mark, the greater the extension of the starting end. Therefore, there is a relationship of d3 (N, 2)> d3 (N, 3) >>...> D3 (N, 8) (N is an integer of 2 to 8).

  As a result, it is possible to correct the difference in the thermal effect of the recording power having formed the immediately preceding recording mark on the starting end of the current recording mark due to the length of the immediately preceding non-recording part, and to correct the difference between the length of the mark starting end due to the recording mark length. The difference between the thermal histories can also be corrected, and the start ends of the recording marks 601 and 602 are formed at correct positions.

  Here, the optical drive waveform is driven between the recording power and the erasing power, but may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.

  FIG. 5 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to a third embodiment of the present invention.

  5, reference numeral 501 denotes a clock generation circuit, 502 denotes a channel clock signal, 503 denotes a recording signal generation circuit, 504 denotes a recording signal output from the recording signal generation circuit 503, 505 denotes an L-level period length measurement circuit, and 506 denotes a measurement result thereof. Output, 507 is an H level period length measurement circuit, 508 is a recording signal after passing through the H level period length measurement circuit 507, 509 is an H level period length measurement result output, 510 is a delay circuit, 511 is a memory, and 512 is a memory output 513, a variable delay unit; 514, a delay unit output; 515, an AND circuit; 516, an output thereof; 517, a laser drive circuit;

  The operation of the above configuration will be described with reference to the timing chart of FIG.

  The clock generation circuit 501 outputs a channel clock 502 whose cycle is the detection window width Tw. The duty is variable.

  The recording signal 504 output from the recording signal generating circuit 503 is input to the L level period length measuring circuit 505 and the H level period length measuring circuit 507 in synchronization with the rise of the channel clock signal 502 from the clock generating circuit 501. .

  The L-level period length measuring circuit 505 measures the L-level period length of the recording signal 504, and outputs a measurement result 506 at the rise of the H level next to the measured L level. That is, if the length of the L-level period is represented by the number of channel clocks, the length of the L-level period T601 is 2, the measurement result 506 becomes 2 at the rise of T602, and the length of the L-level period T603 The measurement result 506 becomes 6 at the rise of T604.

  The H-level period length measuring circuit 507 measures the H-level period length of the recording signal 504, and outputs a measurement result 509 at the rise of the measured H level. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T602 is 5, the measurement result 509 becomes 5 at the rise of T602, and the length of the H-level period T604 Is 8, and the measurement result 509 becomes 8 at the rise of T604.

  Then, the measurement results 506 and 509 are input to the delay circuit 510.

  In the delay circuit 510, the measurement results 506 and 509 are input to the memory 511, and the memory 511 outputs a memory output 512. Here, as shown in Table 3, the memory 511 corresponds to the combination of the length of the immediately preceding non-recorded portion (corresponding to the measurement result 506) and the length of the current recording mark (corresponding to the measurement result 509). And the corresponding stored value is output.

  The variable delay unit 513 delays the recording signal 508 according to the memory output 512 and outputs a signal 514.

  The recording signal 508 and the signal 514 are input to an AND circuit 515 and output as a signal 516.

  The output signal 516 is input to the laser drive circuit 517, and the light source is driven to form an optical drive waveform 518, and the recording marks 601 and 602 are formed.

  As described above, in the third embodiment, when the recording mark 601 or 602 is formed, the recording power of the light source depends on the length of the non-recording portion that should be immediately before and the recording length of the current recording mark. Delay the drive start time. As a result, it is possible to correct the difference in the thermal effect of the recording power having formed the immediately preceding recording mark on the starting end of the current recording mark due to the length of the immediately preceding non-recording part, and to correct the difference between the length of the mark starting end due to the recording mark length. The difference between the thermal histories can also be corrected, and the start ends of the recording marks 601 and 602 are formed at correct positions.

Here, the optical drive waveform is driven between the recording power and the erasing power, but may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 4)
An optical drive waveform 725 in FIG. 8 is an optical drive waveform according to the fourth embodiment of the present invention.

  The optical drive waveform 725 includes a leading pulse and a multi-pulse. Further, the driving start time is delayed from the recording signal 708. In the case of (1, 7) modulation as an example, the delay amount corresponds to the combination of the desired length of the current recording mark and the desired length of the non-recording portion immediately before, as shown in Table 4. I can decide.

  For example, the desired length of the mark 801 is T802 = 5Tw (Tw is the detection window width), and the last non-recording period is T801 = 2Tw, so that the optical drive waveform is delayed by d4 (2,5). Since the desired length of the mark 802 is T804 = 8Tw and the immediately preceding non-recording period is T803 = 6Tw, the optical drive waveform is delayed by d4 (6,8).

  If the length of the mark to be recorded is the same, the shorter the desired length of the immediately preceding non-recorded portion, the greater the thermal effect of the previous recording power, and the more likely the temperature to rise at the start of the mark, thus increasing the extension of the start end. . Therefore, there is a tendency that d4 (2, N)> d4 (3, N) >>...> D4 (8, N) (N is an integer of 2 to 8).

  If the length of the previous unrecorded portion is the same, the shorter the mark length to be recorded this time, the easier the quenching condition at the mark start end is. When a phase-change medium for forming a mark is used, the shorter the mark, the greater the extension of the starting end. Therefore, there is a tendency that d4 (N, 2)> d4 (N, 3) >>...> D4 (N, 8).

  As a result, it is possible to correct the difference in the thermal effect of the recording power having formed the immediately preceding recording mark on the start end of the current recording mark due to the length of the immediately preceding non-recording portion, and to correct the difference in the mark start end due to the recording mark length. The difference between the thermal histories can also be corrected, and the start ends of the recording marks 801 and 802 are formed at correct positions.

  Here, the optical drive waveform is driven between the recording power and the erasing power, but may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.

  FIG. 7 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to a fourth embodiment of the present invention.

  7, reference numeral 701 denotes a clock generation circuit, 702 denotes a channel clock signal, 703 denotes a recording signal generation circuit, 704 denotes a recording signal output from the recording signal generation circuit 703, 705 denotes an L level period length measurement circuit, and 706 denotes the measurement result. Output, 707 is an H level period length measurement circuit, 708 is a recording signal after passing through the H level period length measurement circuit 707, 709 is an H level period length measurement result output, 710 is a delay circuit block, 711 is a memory, and 712 is a memory The output, 713 is a variable delay device, 714 is a pulse division circuit, 715 is a leading pulse signal, 716 is a second half pulse signal, 717 is a multi-pulse generation circuit, and includes an inversion circuit 718 and an AND circuit 719.

  720 is a multi-pulse, 721 is a delay output, 722 is an OR circuit, 723 is its output, 724 is a laser drive circuit, and 725 is an optical drive waveform.

  The operation of the above configuration will be described with reference to the timing chart of FIG.

  The clock generation circuit 701 outputs a channel clock 702 having a cycle of the detection window width Tw. The duty is variable.

  The recording signal 704 output from the recording signal generating circuit 703 is input to the L level period length measuring circuit 705 and the H level period length measuring circuit 707 in synchronization with the rise of the channel clock signal 702 from the clock generating circuit 701. .

  The H-level period length measurement circuit 707 outputs a recording signal 708 again.

  The L level period length measuring circuit 705 measures the L level period length of the recording signal 704, and outputs a measurement result 706 at the rising of the H level next to the measured L level. That is, if the length of the L-level period is represented by the number of channel clocks, the length of the L-level period T801 is 2, the measurement result 706 becomes 2 at the rise of T802, and the length of the L-level period T803 is The measurement result 706 becomes 6 at the rise of T804.

  The H-level period length measurement circuit 707 measures the H-level period length of the recording signal 704, and outputs a measurement result 709 at the rise of the measured H level. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T802 is 5, the measurement result 709 becomes 5 at the rise of T802, and the length of the H-level period T804 is The measurement result 709 becomes 8 at the rise of T804.

  Then, the measurement results 706 and 709 are input to the delay circuit 710.

  In the delay circuit 710, the measurement results 706 and 709 are input to the memory 711, and the memory 711 outputs a memory output 712. Here, as shown in Table 4, the memory 711 corresponds to the combination of the length of the immediately preceding non-recorded portion (corresponding to the measurement result 706) and the length of the current recording mark (corresponding to the measurement result 709). And the corresponding stored value is output.

  On the other hand, the recording signal 708 is input to the pulse division circuit 714, and is divided into a first pulse 715 having a pulse width Tw and a second half pulse 716.

  The leading pulse 715 is delayed according to the memory output 712 by the variable delay unit 713, and becomes a signal 721.

  The second half pulse signal 716 is input to the multi-pulse generation circuit 717 and becomes a multi-pulse 720.

  The signal 721 and the multipulse 720 are input to an OR circuit 722 and output as a signal 723.

  The output signal 723 is input to the laser drive circuit 724, which drives the light source to generate an optical drive waveform 725, and the recording marks 801 and 802 are formed.

  As described above, in the fourth embodiment, when the recording mark 801 or 802 is formed, the recording power is driven in a plurality of pulses consisting of the leading pulse and the multi-pulse, and the length of the non-recording portion that should be immediately before and the current recording time are determined. The drive start time of the first pulse is delayed according to the length of the recording mark to be recorded. As a result, it is possible to correct the difference in the thermal effect of the recording power having formed the immediately preceding recording mark on the starting end of the current recording mark due to the length of the immediately preceding non-recording part, and to correct the difference between the length of the mark starting end due to the recording mark length. The difference between the thermal histories can also be corrected, and the start ends of the recording marks 801 and 802 are formed at correct positions. Further, by driving in a pulse shape, the heat load applied to the medium is reduced, and there is an effect that deterioration due to repeated recording is reduced.

Here, the optical drive waveform is driven between the recording power and the erasing power, but may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 5)
An optical drive waveform 920 in FIG. 10 is an optical drive waveform according to the fifth embodiment of the present invention.

  The drive start time of the optical drive waveform 920 is delayed with respect to the recording signal 910.

  Taking the (1, 7) modulation as an example, as shown in Table 5, the delay amount should be the length of the previous recorded mark, the length of the non-recorded portion immediately before the current mark, and Is determined according to the combination of the lengths of the recording marks.

  For example, the desired length of the mark 1001 is T1003 = 5Tw (Tw is a detection window width), the immediately preceding non-recording period is T1002 = 2Tw, and the previous recording mark is T1001 = 3Tw, so that the optical drive waveform Is delayed by d5 (3, 2, 5), the desired length of the mark 1002 is T1005 = 8Tw, the immediately preceding non-recording period is T1004 = 6Tw, and the previous recording mark is T1003 = 5Tw. The optical drive waveform is delayed by d5 (5, 6, 8).

  If the length of the mark to be recorded is the same and the length of the previous non-recorded portion is the same, the larger the previous recorded mark, the greater the thermal effect of the previous recording power, and the higher the temperature at the start of the mark. The elongation at the starting end increases. Therefore, d5 (8, N, M)> d5 (7, N, M) >>...> D5 (2, N, M) (N and M are integers from 2 to 8).

  Also, if the length of the mark to be recorded is the same and the length of the previous recording mark is the same, the smaller the length of the immediately preceding non-recording portion, the greater the thermal effect of the previous recording power, and the temperature at the beginning of the mark rises. Since the mark is easy to expand, the start of the mark this time increases. Therefore, d5 (N, 2, M)> d5 (N, 3, M) >> ... d5 (N, 8, M) (N and M are integers from 2 to 8).

  Also, if the previous recorded mark length is the same and the length of the previous unrecorded portion is the same, the shorter the mark length to be recorded this time, the easier it is to obtain the quenching condition at the mark start end. When a phase change medium that forms an amorphous mark by quenching afterwards is used, the shorter the mark, the greater the extension of the starting end. Therefore, d5 (N, M, 2)> d5 (N, M, 3) >>...> D5 (N, M, 8), where N and M are integers from 2 to 8.

  As a result, it is possible to correct the difference between the length due to the previous recording mark length and the difference due to the length of the immediately preceding non-recording portion of the thermal effect on the starting end of the current recording mark by the recording power at which the previous recording mark was formed, and The difference in the thermal history of the mark start part due to the recording mark length can also be corrected, and the start parts of the recording marks 1001 and 1002 are formed at correct positions.

  Here, the optical drive waveform is driven between the recording power and the erasing power, but may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.

  FIG. 9 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to Embodiment 5 of the present invention.

  9, reference numeral 901 denotes a clock generation circuit; 902, a channel clock signal; 903, a recording signal generation circuit; 904, a recording signal output from the recording signal generation circuit 903; 905, an H-level period length measurement circuit 1; Result output, 907 is an L level period length measurement circuit, 908 is the measurement result output, 909 is an H level period length measurement circuit 2, 910 is a recording signal after passing through the H level period length measurement circuit 2, 911 is an H level period The measurement result output of the length measurement circuit 2, 912 is a delay circuit, 913 is a memory, 914 is a memory output, 915 is a variable delay, 916 is its output, 917 is an AND circuit, 918 is its output, 919 is a laser drive circuit, 920 is an optical drive waveform.

  The operation of the above configuration will be described with reference to the timing chart of FIG.

  The clock generation circuit 901 outputs a channel clock 902 having a cycle of the detection window width Tw. The duty is variable.

  The recording signal 904 output from the recording signal generation circuit 903 in synchronization with the rise of the channel clock signal 902 from the clock generation circuit 901 includes an H level period length measurement circuit 1 (905) and an L level period length measurement circuit 907 Is input to the H-level period length measurement circuit 2 (909).

  The H level period length measurement circuit 1 (905) measures the H level period length of the recording signal 904, and outputs the result 906 at the next rising of the H level. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T1001 is 3, 3 is output at the next rising edge of the H-level period T1003, and the H-level period T1003 is output. Is 5, and 5 is output at the rise of the next H-level period T1005.

  The L level period length measuring circuit 907 measures the L level period length of the recording signal 904, and outputs the result 908 at the rising of the H level following the L level. That is, if the length of the L-level period is represented by the number of channel clocks, the length of the L-level period T1002 is 2, and 2 is output at the next rise of the H-level period T1003, and the L-level period T1004 Is 6, and 6 is output at the rise of the next H-level period T1005.

  The H level period length measurement circuit 2 (909) measures the H level period length of the recording signal 904, and outputs a result 911 at the rise of the H level. That is, if the length of the H-level period is expressed by the number of channel clocks, the length of the H-level period T1003 is 5, and 5 is output at the rise of the H-level period T1003. The length is 8, and 8 is output at the rise of the H-level period T1005.

  Then, the measurement results 906, 908, and 911 are input to the delay circuit 912.

  In the delay circuit 912, the measurement results 906, 908, and 911 are input to the memory 913, and the memory 913 outputs a memory output 914. Here, as shown in Table 5, the memory 913 should have the length of the previous recording mark (corresponding to the measurement result 906) and the length of the non-recording portion immediately before the current recording mark (the measurement result 908). The value is stored in correspondence with the combination of the corresponding recording mark and the length of the current recording mark (corresponding to the measurement result 911), and the corresponding stored value is output.

  The variable delay unit 915 delays the recording signal 910 according to the memory output 914, and outputs a signal 916.

  The recording signal 910 and the signal 916 are input to an AND circuit 917 and output as a signal 918.

  The output signal 918 is input to the laser drive circuit 919, and the light source is driven to form an optical drive waveform 920, and the recording marks 1001 and 1002 are formed.

  As described above, in the fifth embodiment, when forming the recording mark 1001 or 1002, the length of the previous recording mark, the length of the non-recording portion immediately before the current recording mark, and the recording of the current recording mark The drive start time at the recording power of the light source is delayed according to the combination of lengths to be performed. As a result, it is possible to correct the difference between the previous mark length and the difference between the length of the non-recording portion immediately before the current recording mark and the difference in the thermal effect of the recording power that formed the previous recording mark on the start end of the current recording mark. In addition, since the difference in the thermal history of the mark start end portion due to the recording mark length can be corrected, the start end portions of the recording marks 1001 and 1002 are formed at correct positions.

Here, the optical drive waveform is driven between the recording power and the erasing power, but may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 6)
An optical drive waveform 1127 in FIG. 12 is an optical drive waveform according to the sixth embodiment of the present invention.

  The optical drive waveform 1127 includes a leading pulse and a multi-pulse. Further, in the optical drive waveform 1127, the drive start time is delayed with respect to the recording signal 1110.

  Taking the (1, 7) modulation as an example, as shown in Table 6, the delay amount should be the length of the previous recorded mark, the length of the non-recorded portion immediately before the current mark, and Is determined according to the combination of the lengths of the recording marks.

  For example, the desired length of the mark 1201 is T1203 = 5Tw (Tw is the detection window width), the immediately preceding non-recording period is T1202 = 2Tw, and the previous recording mark is T1201 = 3Tw, so that the optical drive waveform Is delayed by d6 (3, 2, 5), the desired length of the mark 1202 is T1205 = 8Tw, the immediately preceding non-recording period is T1204 = 6Tw, and the previous recording mark is T1203 = 5Tw. The optical drive waveform is delayed by d6 (5, 6, 8).

  If the length of the mark to be recorded is the same and the length of the previous non-recorded portion is the same, the larger the previous recorded mark, the greater the thermal effect of the previous recording power, and the higher the temperature at the start of the mark. The elongation at the starting end increases. Therefore, there is a tendency that d6 (8, N, M)> d6 (7, N, M) >>...> D6 (2, N, M) (N and M are integers from 2 to 8).

  Also, if the length of the mark to be recorded is the same and the length of the previous recording mark is the same, the smaller the length of the immediately preceding non-recording portion, the greater the thermal effect of the previous recording power, and the temperature at the beginning of the mark rises. Since the mark is easy to expand, the start of the mark this time increases. Therefore, there is a tendency that d6 (N, 2, M)> d6 (N, 3, M) >>...> D6 (N, 8, M) (N and M are integers from 2 to 8).

  Also, if the previous recorded mark length is the same and the length of the previous unrecorded portion is the same, the shorter the mark length to be recorded this time, the easier it is to obtain the quenching condition at the mark start end. When a phase change medium that forms an amorphous mark by quenching afterwards is used, the shorter the mark, the greater the extension of the starting end. Therefore, there is a tendency that d6 (N, M, 2)> d6 (N, M, 3) >>...> D6 (N, M, 8).

  As a result, it is possible to correct the difference between the length due to the previous recording mark length and the difference due to the length of the immediately preceding non-recording portion of the thermal effect on the starting end of the current recording mark by the recording power at which the previous recording mark was formed, and The difference in the thermal history of the mark start part due to the recording mark length can also be corrected, and the start parts of the recording marks 1001 and 1002 are formed at correct positions.

  Here, the optical drive waveform is driven between the recording power and the erasing power, but may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.

  FIG. 11 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to a sixth embodiment of the present invention.

  In FIG. 11, reference numeral 1101 denotes a clock generation circuit; 1102, a channel clock signal; 1103, a recording signal generation circuit; 1104, a recording signal output from the recording signal generation circuit 1103; Result output, 1107 is an L level period length measurement circuit, 1108 is the measurement result output, 1109 is an H level period length measurement circuit 2, 1110 is a recording signal after passing through the H level period length measurement circuit 2, and 1111 is an H level period Output of the measurement result of the length measurement circuit 2, 1112 is a delay circuit, 1113 is a memory, 1114 is a memory output, 1115 is a variable delay device, 1116 is a pulse division circuit, 1117 is a leading pulse signal, 1118 is a latter pulse signal, and 1119 is a multi-pulse signal. It is a pulse generation circuit, and is composed of an inversion circuit 1120 and an AND circuit 1121. It is.

  Reference numeral 1122 denotes a multipulse, 1123 denotes a variable delay output, 1124 denotes an OR circuit, 1125 denotes its output, 1126 denotes a laser drive circuit, and 1127 denotes an optical drive waveform.

  The operation of the above configuration will be described with reference to the timing chart of FIG.

  The clock generation circuit 1101 outputs a channel clock 1102 whose cycle is a detection window width Tw. The duty is variable.

  The recording signal 1104 output from the recording signal generation circuit 1103 in synchronization with the rise of the channel clock signal 1102 from the clock generation circuit 1101 includes an H level period length measurement circuit 1 (1105) and an L level period length measurement circuit 1107. Is input to the H-level period length measurement circuit 2 (1109).

  The H level period length measuring circuit 1 (1105) measures the H level period length of the recording signal 1104, and outputs the result 1106 at the next rising of the H level. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T1201 is 3, and 3 is output at the next rise of the H-level period T1203, and the H-level period T1203 is output. Is 5, and 5 is output at the rising edge of the next H-level period T1205.

  The L-level period length measurement circuit 1107 measures the L-level period length of the recording signal 1104, and outputs the result 1108 at the rising of the H level following the L level. That is, if the length of the L-level period is represented by the number of channel clocks, the length of the L-level period T1202 is 2, and 2 is output at the next rise of the H-level period T1203, and the L-level period T1204 Is 6, and 6 is output at the rise of the next H-level period T1205.

  The H level period length measurement circuit 2 (1109) measures the H level period length of the recording signal 1104, and outputs the result 1111 in synchronization with the rise of the H level. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T1203 is 5, and 5 is output at the rise of the H-level period T1203. The length is 8, and 8 is output at the rise of the H-level period T1205.

  Then, the measurement results 1106, 1108, and 1111 are input to the delay circuit 1112.

  In the delay circuit 1112, the measurement results 1106, 1108, and 1111 are input to a memory 1113, and a memory output 1114 is output from the memory 1113. Here, as shown in Table 6, the memory 1113 stores the length of the previous recording mark (corresponding to the measurement result 1106) and the length of the non-recording portion immediately before the current recording mark (corresponding to the measurement result 1108). A value is stored in correspondence with a combination of the corresponding recording mark and the length of the current recording mark (corresponding to the measurement result 1111), and the corresponding stored value is output.

  On the other hand, the recording signal 1110 is divided by the pulse division circuit 1116 into a first pulse 1117 and a second half pulse 1118.

  The first pulse is a signal that rises at the rise of the recording signal 1110 and falls after Tw, and the second half pulse is a signal that rises Tw after the rise of the recording signal 1110 and falls at the fall of the recording signal 1110.

  The latter half pulse 1118 is input to the multi-pulse generation circuit 1119, and the multi-pulse 1122 is output.

  The leading pulse 1117 is delayed by the variable delay 1115 according to the memory output 1114 to become a signal 1123.

  The multipulse 1122 and the signal 1123 are input to an OR circuit 1124 and output as a signal 1125.

  The output signal 1125 is input to the laser drive circuit 1126 to drive the light source to form an optical drive waveform 1127, and the recording marks 1201 and 1202 are formed.

  As described above, in the sixth embodiment, when forming the recording mark 1201 or 1202, the light source emits light in a pulse shape, and the length of the previous recording mark and the length of the non-recording portion that should be immediately before the current recording mark are determined. The drive start time of the first pulse is delayed according to the combination of the length and the length of the current recording mark to be recorded. As a result, it is possible to correct the difference between the previous mark length and the difference between the length of the non-recording portion immediately before the current recording mark and the difference in the thermal effect of the recording power that formed the previous recording mark on the start end of the current recording mark. In addition, since the difference in the thermal history of the mark start part due to the recording mark length can be corrected, the start parts of the record marks 1201 and 1202 are formed at the correct positions. Further, by driving in a pulsed manner, the heat load applied to the medium can be reduced, and there is an effect that deterioration due to repeated recording is reduced.

Here, the optical drive waveform is driven between the recording power and the erasing power, but may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 7)
An optical drive waveform 1318 in FIG. 14 is an optical drive waveform according to the seventh embodiment of the present invention.

  In the optical drive waveform 1318, the drive end time is earlier than the reference signal 1314 in which the recording signal 1306 is delayed by a fixed amount K.

  The amount of the change is determined according to the length of the recording mark to be recorded as shown in Table 7 in the case of (1, 7) modulation as an example.

  For example, since the recording length of the recording mark 1401 is T1401 = 2 Tw (Tw is the detection window width), only d7 (2) ends quickly, and the recording length of the recording mark 1402 is T1402 = 8Tw. Therefore, the processing ends earlier by d7 (8).

  The longer the mark length to be recorded, the greater the effect of heat accumulation at the end of the mark, and the greater the extension of the end. Therefore, there is a tendency that d7 (8)> d7 (7) >>...> D7 (2).

  As a result, it is possible to correct the difference in the heat accumulation at the end portions of the marks due to the recording mark length, and the end portions of the recording marks 1401 and 1402 are formed at the correct positions.

  Note that here, the optical drive waveform 1318 is driven between the recording power and the erasing power. However, if the optical driving waveform 1318 is driven according to the recording medium, such as between the recording power and the reproducing power, or between the recording power and 0. Good.

  FIG. 13 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to the seventh embodiment of the present invention.

  13, reference numeral 1301 denotes a clock generation circuit, 1302 denotes a clock signal, 1303 denotes a recording signal generation circuit, 1304 denotes a recording signal output from the recording signal generation circuit 1303, 1305 denotes an H level period length measuring circuit, and 1306 denotes an H level period length. The recording signal after passing through the measurement circuit 1305, 1307 is an H level period measurement result output, 1308 is a delay circuit, 1309 is a memory, 1310 is a memory output, 1311 is a variable delay device, 1312 is a variable delay device output, and 1313 is a fixed delay 1314, its output, 1315, an AND circuit, 1316, its output, 1317, a laser drive circuit, and 1318, an optical drive waveform.

  The operation of the above configuration will be described with reference to the timing chart of FIG.

  The clock generation circuit 1301 outputs a channel clock 1302 whose cycle is the detection window width Tw. The duty is variable.

  The recording signal 1304 output from the recording signal generation circuit 1303 is input to the H-level period length measurement circuit 1305 in synchronization with the rise of the channel clock signal 1302 from the clock generation circuit 1301. The H level period length measuring circuit 1305 measures the length of the H level period of the recording signal 1304, and outputs the recording signal 1306 and the measurement result 1307 again. The measurement result 1307 is output in synchronization with the measured rise of the H level of the recording signal 1306. That is, if the length of the H level period is represented by the number of channel clocks, the length of the H level period T1401 is 2, and the measurement result 1307 becomes 2 at the rise of the H level period T1401, and the H level period The length of T1402 is 8, and the measurement result 1307 becomes 8 at the rise of the H-level period T1402.

  Then, the measurement result 1307 is input to the delay circuit 1308.

  In the delay circuit 1308, the measurement result 1307 is input to the memory 1309, and the memory 1309 outputs the memory output 1310. Here, as shown in Table 7, the memory 1309 stores a value corresponding to the length of the current recording mark (corresponding to the measurement result 1307), and outputs the stored value corresponding to the measurement result 1307. Is done.

  The variable delay unit 1311 delays the recording signal 1306 according to the memory output 1310 and outputs a signal 1312.

  On the other hand, the recording signal 1306 passes through a fixed delay unit 1313 having a delay amount K and becomes an output 1314 delayed by K.

  The output 1312 and the output 1314 are input to an AND circuit 1315 and output as a signal 1316.

  The output signal 1316 is input to the laser driving circuit 1317, and the light source is driven to generate an optical driving waveform 1318, and recording marks 1401 and 1402 are formed.

  As described above, in the seventh embodiment, when the recording mark 1401 or 1402 is formed, the driving with the recording power of the light source is terminated early according to the recording length of the recording mark. This makes it possible to correct the difference in heat accumulation at the end of the mark due to the above, and to form the end of the recording mark at the correct position.

Here, the optical drive waveform is driven between the recording power and the erasing power, but it may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 8)
An optical drive waveform 1538 in FIG. 16 is an optical drive waveform according to the eighth embodiment of the present invention.

  The optical drive waveform 1538 is composed of a plurality of pulses. Further, the optical drive waveform 1538 has the drive end time of the last pulse earlier with reference to the signal 1600 obtained by delaying the recording signal 1506 by a fixed amount K.

  The change amount is determined in correspondence with the length of a recording mark to be recorded, as shown in Table 8, taking (1, 7) modulation as an example.

  For example, since the recording length of the recording mark 1601 is T1601 = 2 Tw (Tw is the detection window width), only d8 (2) ends quickly, and the recording length of the recording mark 1602 is T1602 = 8 Tw. Therefore, the processing ends earlier by d8 (8).

  The longer the mark length to be recorded, the greater the effect of heat accumulation at the end of the mark, and the greater the extension of the end. Therefore, there is a tendency that d8 (8)> d8 (7) >>...> D8 (2).

  As a result, it is possible to correct the difference in heat accumulation at the end of the mark due to the length of the recording mark, and the end of the recording marks 1601 and 1602 is formed at the correct position.

  Note that here, the optical drive waveform 1538 is driven between the recording power and the erasing power, but if the driving is performed in accordance with the recording medium, such as between the recording power and the reproducing power, or between the recording power and 0. Good.

  FIG. 15 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to Embodiment 8 of the present invention.

  15, 1501 is a clock generation circuit, 1502 is a clock signal, 1503 is a recording signal generation circuit, 1504 is a recording signal output from the recording signal generation circuit 1503, 1505 is an H level period length measurement circuit, and 1506 is an H level period length. The recording signal after passing through the measuring circuit 1505, 1507 is an H level period measurement result output, 1508 is a pulse dividing circuit, 1509 is a leading pulse, 1510 is an intermediate pulse, 1511 is a last pulse, 1512 is a fixed delay device, and 1513 is its output. , 1514 is a multi-pulse generation circuit, 1515 is an inversion circuit, 1516 is an AND circuit, 1517 is an intermediate multi-pulse, 1518 is a fixed delay device, 1519 is its output, 1520 is a multi-pulse generation circuit, 1521 is an inversion circuit, and 1522 is AND. Circuit, 1523 is the last multi circuit, 1 24 is a selector, 1525 is its output, 1526 is a delay circuit, 1527 is a memory, 1528 is a memory output, 1529 is a variable delay, 1530 is its output, 1531 is its OR circuit, 1532 is its output, 1533 is its AND circuit, 1534 Is an output, 1535 is a selector, 1536 is its output, 1537 is a laser drive circuit, 1538 is an optical drive waveform, 1539 is a gate generation circuit, 1540 is its output, 1541 is a switch, and 1542 is a select signal. Here, the selectors 1524 and 1535 select and output the X input when the select signal 1542 is at the L level, and select and output the Y input when the select signal 1542 is at the H level.

  First, the operation when the switch 1541 is OFF, that is, when the select signal 1542 is at the L level will be described with reference to the timing chart of FIG.

  The clock generation circuit 1501 outputs a channel clock 1502 whose cycle is the detection window width Tw. The duty is variable.

  The recording signal 1504 output from the recording signal generation circuit 1503 is input to the H-level period length measurement circuit 1505 in synchronization with the rise of the channel clock signal 1502 from the clock generation circuit 1501. An H-level period length measuring circuit 1505 measures the length of the H-level period of the recording signal 1504, and outputs a recording signal 1506 and a measurement result 1507 again. The measurement result 1507 is output in synchronization with the rising of the measured H level of the recording signal 1506. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T1601 is 2, and the measurement result 1507 becomes 2 at the rise of the H-level period T1601, and The length of T1602 is 8, and the measurement result 1507 becomes 8 at the rise of the H-level period T1602.

  Then, the measurement result 1507 is input to the delay circuit 1526. In the delay circuit 1526, the measurement result 1507 is input to the memory 1527, and the memory 1527 outputs the memory output 1528. Here, as shown in Table 8, the memory 1527 stores a value corresponding to the length of the current recording mark (corresponding to the measurement result 1507), and outputs the stored value corresponding to the measurement result 1507. Is done.

  On the other hand, the recording signal 1506 is divided into a leading pulse 1509, an intermediate pulse 1510, and a last pulse 1511 by a pulse dividing circuit 1508. In this example, the top pulse 1509 is a signal that rises at the rise of the recording signal 1506 and falls after Tw, and the intermediate pulse 1510 rises Tw after the rise of the recording signal 1506 and falls before Tw, the fall of the recording signal 1506. The last pulse 1511 is a signal which rises before Tw of the fall of the recording signal 1506 and falls at the fall of the recording signal 1506. When the H level period of the recording signal 1506 is 2 Tw, no intermediate pulse is generated.

  The first pulse 1509 is delayed by the fixed delay unit 1512 having the delay amount K to become a signal 1513.

  The intermediate pulse 1510 is input to the multi-pulse generation circuit 1514, becomes an intermediate multi-pulse 1517, is delayed by a fixed delay unit 1518 having a delay amount K, and becomes a signal 1519.

  The last pulse 1511 becomes a last multipulse 1523 in the multipulse generation circuit 1520, is selected by the selector 1524, becomes a signal 1525, is delayed by the variable delay unit 1529 according to the memory output 1528, and becomes a signal 1530.

  The output 1532 of the signal 1519, the signal 1513, and the signal 1530 by the OR circuit 1531 is selected by the selector 1535 and input to the laser driving circuit 1537, and the light source is driven to form the optical driving waveform 1538, and the recording marks 1601 and 1602 are formed. .

  Next, the case where the switch 1541 is ON will be described with reference to FIG.

  Gate generation circuit 1539 outputs an H level only when measurement result 1507 is 2. Therefore, the select signal 1542 becomes H level when the measurement result 1507 is 2, and the selectors 1524 and 1535 select and output the Y input. Therefore, the last pulse 1511 is input to the variable delay unit 1529 and is delayed to be a signal 1530. Further, an output 1534 of the signal 1513 and the signal 1530 by the AND circuit 1533 is guided to the laser driving circuit 1537. Therefore, when the mark to be recorded is 2 Tw, a pulse width equal to or smaller than Tw can be created, and smaller marks can be handled.

  When the measurement result 1507 is other than 2, it is the same as when the switch 1541 is OFF.

  As described above, in the eighth embodiment, when the recording mark 1601 or 1602 is formed, the driving is performed with a plurality of pulses, and the driving of the last pulse is terminated early according to the length of the recording mark to be recorded. The difference in heat accumulation at the end of the mark due to the length of the recording mark can be corrected, and the end of the recording mark can be formed at the correct position. Further, by driving in a plurality of pulses, the heat load applied to the medium can be reduced, and there is also an effect of reducing deterioration due to repeated recording.

  By changing the method of dividing the leading pulse, the intermediate pulse, and the last pulse by the pulse dividing circuit, various pulse patterns can be handled.

Here, the optical drive waveform is driven between the recording power and the erasing power, but it may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 9)
An optical drive waveform 1820 in FIG. 19 is an optical drive waveform according to the ninth embodiment of the present invention.

  In the optical drive waveform 1820, the drive end time is earlier than the reference signal 1816, which is the recording signal 1806 delayed by a fixed amount K.

  The amount of change is determined according to the combination of the length of a recording mark to be recorded and the length of a non-recording portion to be immediately after, as shown in Table 9, taking (1, 7) modulation as an example. .

  For example, the length of the recording mark 1901 to be recorded is T1901 = 5Tw (Tw is the detection window width), and the length of the non-recording portion immediately after is T1902 = 6Tw, so that the optical drive waveform 1820 is d9 (5,5). Only 6) ends quickly, the length of the recording mark 1902 to be recorded is T1903 = 8Tw, and the length of the non-recording portion immediately after is T1904 = 2Tw, so that the process ends earlier by d9 (8,2).

  If the length of the unrecorded portion immediately after is the same, the longer the length of the mark to be recorded, the greater the effect of heat accumulation at the end of the mark and the greater the extension of the end. Therefore, there is a tendency that d9 (8, N)> d9 (7, N) >>...> D9 (2, N).

  If the length of the recording mark is the same, the shorter the length of the non-recording portion immediately after, the lower the temperature of the mark end portion becomes, and the longer the end of the mark becomes. Therefore, there is a tendency that d9 (N, 2)> d9 (N, 3) >>...> D9 (N, 8).

  As a result, it is possible to correct the difference in heat accumulation at the end of the mark due to the length of the recording mark and the difference in the thermal history at the end of the mark due to the length of the non-recording portion immediately after. It is formed.

  Here, the optical drive waveform 1820 is driven between the recording power and the erasing power. However, if the optical driving waveform 1820 is driven according to the recording medium, such as between the recording power and the reproducing power, or between the recording power and 0. Good.

  FIG. 18 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to Embodiment 9 of the present invention.

  In FIG. 18, reference numeral 1801 denotes a clock generation circuit, 1802 denotes a clock signal, 1803 denotes a recording signal generation circuit, 1804 denotes a recording signal output from the recording signal generation circuit 1803, 1805 denotes an H level period length measuring circuit, and 1806 denotes an H level period length. A recording signal after passing through the measurement circuit 1805, 1807 is an H level period measurement result output, 1808 is an L level period length measurement circuit, 1809 is the measurement result output, 1810 is a delay circuit, 1811 is a memory, 1812 is a memory output, and 1813 is a memory output. Is a variable delay unit, 1814 is a variable delay unit output, 1815 is a fixed delay unit, 1816 is its output, 1817 is an AND circuit, 1818 is its output, 1819 is a laser drive circuit, and 1820 is an optical drive waveform.

  The operation of the above configuration will be described with reference to the timing chart of FIG.

  The clock generation circuit 1801 outputs a channel clock 1802 whose cycle is the detection window width Tw. The duty is variable.

  The recording signal 1804 output from the recording signal generation circuit 1803 is input to the H-level period length measurement circuit 1805 in synchronization with the rise of the channel clock signal 1802 from the clock generation circuit 1801. The H level period length measuring circuit 1805 measures the length of the H level period of the recording signal 1804, and outputs a recording signal 1806 and a measurement result 1807 again. The measurement result 1807 is output in synchronization with the rise of the measured H level of the recording signal 1806. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T1901 is 5, the measurement result 1807 is 5 at the rise of the H-level period T1901, and the H-level period is T1901. The length of T1903 is 8, and the measurement result 1807 becomes 8 at the rise of the H-level period T1903.

  The recording signal 1804 is input to the L-level period length measuring circuit 1808. The L level period length measuring circuit 1808 measures the length of the L level period of the recording signal 1804, and outputs a measurement result 1809. The measurement result 1809 is output in synchronization with the rise of the H level immediately before the measured L level. That is, if the length of the L-level period is represented by the number of channel clocks, the length of the L-level period T1902 is 6, and the measurement result 1809 becomes 6 at the rising edge of the immediately preceding H-level period T1901, The length of the L level period T1904 is 8, and the measurement result 1809 becomes 8 at the rise of the immediately preceding H level period T1903.

  Then, the measurement results 1807 and 1809 are input to the delay circuit 1810.

  In the delay circuit 1810, the measurement results 1807 and 1809 are input to a memory 1811, and a memory output 1812 is output from the memory 1811. Here, as shown in Table 9, the memory 1811 stores the combination of the length of the current recording mark (corresponding to the measurement result 1807) and the length of the immediately non-recorded portion (corresponding to the measurement result 1809). The corresponding value is stored, and the corresponding stored value is output.

  The variable delay unit 1813 delays the recording signal 1806 according to the memory output 1812 and outputs a signal 1814.

  On the other hand, the recording signal 1806 passes through a fixed delay unit 1815 having a delay amount K, and becomes a signal 1816 delayed by K.

  The signals 1814 and 1816 are input to an AND circuit 1817 and output as a signal 1818.

  The output signal 1818 is input to the laser driving circuit 1819, and the light source is driven to form an optical driving waveform 1820, and recording marks 1901 and 1902 are formed.

  As described above, in the ninth embodiment, when forming the recording marks 1901 and 1902, the recording power of the light source depends on the combination of the recording length of the recording mark and the length of the non-recording portion immediately after. Since the driving is completed early, it is possible to correct a difference in heat accumulation at the end of the mark due to the length of the recording mark, and to correct a difference in heat history at the end of the mark due to the length of the immediately following non-recorded portion. Therefore, the end portion of the recording mark can be formed at a correct position.

Here, the optical drive waveform is driven between the recording power and the erasing power, but it may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 10)
An optical drive waveform 2038 in FIG. 21 is an optical drive waveform according to the tenth embodiment of the present invention.

  The optical drive waveform 2038 is composed of a plurality of pulses. Further, with respect to the optical drive waveform 2038, the drive end time of the last pulse is earlier with respect to the signal 2100 obtained by delaying the recording signal 2006 by a fixed amount K.

  The change amount is determined according to a combination of the length of a recording mark to be recorded and the length of a non-recording portion immediately after recording, as shown in Table 10, taking (1, 7) modulation as an example. Can be

  For example, the length of the recording mark 2101 to be recorded is T2101 = 2Tw (Tw is the detection window width), and the length of the non-recording portion immediately after is T2102 = 4Tw, so only d10 (2,4) The recording mark 2102 is to be recorded quickly, and the length to be recorded is T2103 = 8Tw, and the length of the non-recording portion immediately after is T2104 = 3Tw, so that the recording is completed earlier by d10 (8,3).

  If the length of the unrecorded portion immediately after is the same, the longer the mark length to be recorded, the greater the effect of heat accumulation at the end portion of the mark and the greater the extension of the end portion. Therefore, there is a tendency that d10 (8, N)> d10 (7, N) >>...> D10 (2, N) (N is an integer of 2 to 8).

  Further, if the length of the mark to be recorded is the same, the shorter the length of the immediately unrecorded portion, the more difficult it is for the temperature at the end portion of the mark to decrease, and the greater the extension of the end portion. Therefore, there is a tendency that d10 (N, 2)> d10 (N, 3) >>...> D10 (N, 8) (N is an integer of 2 to 8).

  As a result, the difference in heat accumulation at the end of the mark due to the length of the recording mark can be corrected, and the difference in the thermal history at the end of the mark due to the length of the immediately unrecorded portion can be corrected. Is formed in the correct position.

  Here, the optical drive waveform 2038 is driven between the recording power and the erasing power. However, if the driving is performed in accordance with the recording medium, such as between the recording power and the reproducing power, or between the recording power and 0. Good.

  FIG. 20 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to Embodiment 10 of the present invention.

  20, reference numeral 2001 denotes a clock generation circuit, 2002 denotes a clock signal, 2003 denotes a recording signal generation circuit, 2004 denotes a recording signal output from the recording signal generation circuit 2003, 2005 denotes an H level period length measuring circuit, and 2006 denotes an H level period length. The recording signal after passing through the measurement circuit 2005, 2007 is an H level period measurement result output, 2008 is a pulse division circuit, 2009 is a leading pulse, 2010 is an intermediate pulse, 2011 is a last pulse, 2012 is a fixed delay device, and 2013 is its output. , 2014 is a multi-pulse generation circuit, 2015 is an inversion circuit, 2016 is an AND circuit, 2017 is an intermediate multi-pulse, 2018 is a fixed delay device, 2019 is its output, 2020 is a multi-pulse generation circuit, 2021 is an inversion circuit, and 2022 is AND. Circuit, 2023 is a last multi circuit, 2 24 is a selector, 2025 is its output, 2026 is a delay circuit, 2027 is a memory, 2028 is a memory output, 2029 is a variable delay device, 2030 is its output, 2031 is an OR circuit, 2032 is its output, 2033 is an AND circuit, and 2034 Is an output, 2035 is a selector, 2036 is its output, 2037 is a laser drive circuit, 2038 is an optical drive waveform, 2039 is a gate generation circuit, 2040 is its output, 2041 is a switch, and 2042 is a select signal. Here, the selectors 2024 and 2035 select and output the X input when the select signal 2042 is at the L level, and select and output the Y input when the select signal 2042 is at the H level. Reference numeral 2043 denotes an L-level period length measurement circuit, and reference numeral 2044 denotes a measurement result output.

  First, the operation when the switch 2041 is off, that is, when the select signal 2042 is at the L level, will be described with reference to the timing chart of FIG.

  The clock generation circuit 2001 outputs a channel clock 2002 whose cycle is the detection window width Tw. The duty is variable.

  The recording signal 2004 output from the recording signal generation circuit 2003 is input to the H-level period length measurement circuit 2005 and the L-level period length measurement circuit 2043 in synchronization with the rise of the channel clock signal 2002 from the clock generation circuit 2001. .

  The H-level period length measuring circuit 2005 measures the length of the H-level period of the recording signal 2004, and outputs the recording signal 2006 and the measurement result 2007 again. The measurement result 2007 is output in synchronization with the rise of the measured H level of the recording signal 2006. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T2101 is 2, and the measurement result 2007 becomes 2 at the rise of the H-level period T2101. The length of T2103 is 8, and the measurement result 2007 becomes 8 at the rise of the H-level period T2103.

  The L-level period length measuring circuit 2043 measures the length of the L-level period of the recording signal 2004, and outputs a measurement result 2044. The measurement result 2044 is output in synchronization with the rise of the H level immediately before the measured L level of the recording signal 2006. That is, if the length of the L level period is represented by the number of channel clocks, the length of the L level period T2102 is 4, the measurement result 2044 becomes 4 at the rise of the immediately preceding H level period T2101, and the L level period The length of T2104 is 3, and the measurement result 2044 becomes 3 at the rise of the immediately preceding H-level period T2103.

  Then, the measurement results 2007 and 2044 are input to the delay circuit 2026. In the delay circuit 2026, the measurement results 2007 and 2044 are input to the memory 2027, and a memory output 2028 is output from the memory 2027. Here, in the memory 2027, as shown in Table 10, the combination of the desired length of the current recording mark (corresponding to the measurement result 2007) and the desired length of the immediately non-recorded portion (corresponding to the measurement result 2044) is stored. The corresponding value is stored, and the corresponding stored value is output.

  On the other hand, the recording signal 2006 is divided by a pulse dividing circuit 2008 into a leading pulse 2009, an intermediate pulse 2010, and a last pulse 2011. In this example, the leading pulse 2009 is a signal that rises at the rise of the recording signal 2006 and falls after Tw, and the intermediate pulse 2010 rises Tw after the rise of the recording signal 2006 and falls before Tw, the fall of the recording signal 2006. The last pulse 2011 is a signal that rises before Tw of the fall of the recording signal 2006 and falls at the fall of the recording signal 2006. When the H level period of the recording signal 2006 is 2 Tw, no intermediate pulse is generated.

  The first pulse 2009 is delayed by the fixed delay unit 2012 with the delay amount K and becomes a signal 2013.

  The intermediate pulse 2010 is input to the multi-pulse generation circuit 2014, becomes an intermediate multi-pulse 2017, is delayed by a fixed delay unit 2018 having a delay amount K, and becomes a signal 2019.

  The last pulse 2011 becomes a last multipulse 2023 in the multipulse generation circuit 2020, is selected by the selector 2024, becomes a signal 2025, is delayed by the variable delay unit 2029 according to the memory output 2028, and becomes a signal 2030.

  An output 2032 of the signal 2019, the signal 2013, and the signal 2030 by the OR circuit 2031 is selected by the selector 2035, input to the laser driving circuit 2037, the light source is driven, and the light driving waveform 2038 is formed, and the recording marks 2101 and 2102 are formed. .

  Next, the case where the switch 2041 is ON will be described with reference to FIG.

  Gate generation circuit 2039 outputs an H level only when measurement result 2007 is 2. Therefore, the select signal 2042 becomes H level when the measurement result 2007 is 2, and the selectors 2024 and 2035 select and output the Y input. Therefore, the last pulse 2011 is input to the variable delay unit 2029 and is delayed to become a signal 2030. Further, an output 2034 of the signal 2013 and the signal 2030 by the AND circuit 2033 is guided to the laser driving circuit 2037. Therefore, when the mark to be recorded is 2 Tw, a pulse width equal to or smaller than Tw can be created, and smaller marks can be handled.

  When the measurement result 2007 is other than 2, it is the same as when the switch 2041 is OFF.

  As described above, in the tenth embodiment, when the recording mark 2101 or 2102 is formed, the recording mark 2101 or 2102 is driven by a plurality of pulses, and the recording mark is recorded in accordance with the combination of the recording length of the recording mark and the length of the immediately following non-recording portion. As a result, since the driving of the last pulse is terminated early, it is possible to correct the difference in heat accumulation at the end of the mark due to the length of the recording mark, and to reduce the heat at the end of the mark due to the length of the non-recording portion immediately after. Since the difference between the histories can be corrected, the end portion of the recording mark can be formed at a correct position. Further, by driving in a plurality of pulses, the heat load applied to the medium can be reduced, and there is also an effect of reducing deterioration due to repeated recording.

  By changing the method of dividing the leading pulse, the intermediate pulse, and the last pulse by the pulse dividing circuit, various pulse patterns can be handled.

Here, the optical drive waveform is driven between the recording power and the erasing power, but it may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 11)
An optical drive waveform 2321 in FIG. 24 is an optical drive waveform in the eleventh embodiment of the present invention. In the optical drive waveform 2321, the drive start time at the recording power is delayed and the drive end time is earlier than the reference signal 2400 obtained by delaying the recording signal 2306 by a fixed amount K.

  The delay amount of the drive start time and the change amount of the drive end time (how quickly the drive end time) are determined by the length of the recording mark to be recorded as shown in Table 11 in the case of (1, 7) modulation. Is determined according to

  For example, since the length of the recording mark 2401 to be recorded is T2401 = 2 Tw (Tw is the detection window width), the driving start time of the recording power of the optical driving waveform 2321 is delayed by B11 (2), and the ending time is E11. Only (2) ends quickly. Since the length of the recording mark 2402 to be recorded is T2402 = 8Tw, the drive start time of the recording power of the optical drive waveform 2321 is delayed by B11 (8), and the end time is ended only by E11 (8).

  The shorter the length of the mark to be recorded, the easier the quenching condition after the temperature rise at the mark start end is. Therefore, when the phase change medium is used, the extension of the mark start end increases. Therefore, there is a tendency that B11 (2)> B11 (3) >>...> B11 (8).

  The longer the mark length to be recorded, the greater the effect of heat accumulation at the end of the mark, and the greater the extension of the end. Therefore, there is a tendency that E11 (8)> E11 (7) >>...> E11 (2).

  As a result, it is possible to correct the difference in heat history at the mark start end portion due to the recording mark length and the difference in heat accumulation at the mark end portion due to the recording mark length, and the start and end portions of the recording marks 2401 and 2402 are formed at the correct positions. You.

  Note that here, the optical drive waveform 2321 is driven between the recording power and the erasing power, but if it is driven in accordance with the recording medium, such as between the recording power and the reproducing power, or between the recording power and 0. Good.

  FIG. 23 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to Embodiment 11 of the present invention.

  23, reference numeral 2301 denotes a clock generation circuit, 2302 denotes a clock signal, 2303 denotes a recording signal generation circuit, 2304 denotes a recording signal output from the recording signal generation circuit 2303, 2305 denotes an H level period length measuring circuit, and 2306 denotes an H level period length. The recording signal after passing through the measurement circuit 2305, 2307 is an H level period measurement result output, 2308 is a first delay circuit, 2309 is a first memory, 2310 is a first memory output, 2311 is a first variable delay unit, and 2312 is a first variable delay unit. Output, 2313 is a second delay circuit, 2314 is a second memory, 2315 is a second memory output, 2316 is a second variable delay, 2317 is its output, 2318 is an AND circuit, 2319 is its output, 2320 is a laser drive circuit , 2321 are optical drive waveforms.

  The operation of the above configuration will be described with reference to the timing chart of FIG.

  The clock generation circuit 2301 outputs a channel clock 2302 whose cycle is the detection window width Tw. The duty is variable.

  The recording signal 2304 output from the recording signal generation circuit 2303 is input to the H-level period length measurement circuit 2305 in synchronization with the rise of the channel clock signal 2302 from the clock generation circuit 2301. The H level period length measuring circuit 2305 measures the length of the H level period of the recording signal 2304, and outputs a recording signal 2306 and a measurement result 2307 again. The measurement result 2307 is output in synchronization with the rising of the measured H level of the recording signal 2306. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T2401 is 2, the measurement result 2307 becomes 2 at the rise of the H-level period T2401, and The length of T2402 is 8, and the measurement result 2307 becomes 8 at the rise of the H-level period T2402.

  Then, the measurement result 2307 is input to the first delay circuit 2308 and the second delay circuit 2313.

  In the first delay circuit 2308, the measurement result 2307 is input to the first memory 2309, and the first memory 2309 outputs the first memory output 2310. Here, as shown in Table 11, values are stored in the memory 2309 corresponding to the length of the current recording mark (corresponding to the measurement result 2307), and the corresponding stored value is output. The first variable delay unit 2311 delays the recording signal 2306 and outputs a signal 2312 according to the first memory output 2310.

  In the second delay circuit 2313, the measurement result 2307 is input to the second memory 2314, and the second memory 2314 outputs the second memory output 2315. Here, as shown in Table 11, a value corresponding to the length of the current recording mark (corresponding to the measurement result 2307) is stored in the second memory 2314, and the corresponding stored value is output. . The second variable delay unit 2316 delays the recording signal 2306 according to the second memory output 2315 and outputs a signal 2317.

  The signal 2312 and the signal 2317 are input to an AND circuit 2318 and output as a signal 2319.

  The output signal 2319 is input to the laser driving circuit 2320, and the light source is driven to form an optical driving waveform 2321, and recording marks 2401, 2402 are formed.

  As described above, in the eleventh embodiment, when forming the recording marks 2401 and 2402, the drive start time at the recording power is delayed according to the length of the recording mark to be recorded, and the recording start time is changed according to the length of the recording mark. The difference between the thermal histories at the start of the mark is corrected, and the drive end time at the recording power is ended earlier, so that the difference in heat accumulation at the end of the mark due to the length of the record mark is corrected. , The end portion can be formed in the correct position.

Here, the optical drive waveform is driven between the recording power and the erasing power, but it may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 12)
An optical drive waveform 2541 in FIG. 26 is an optical drive waveform in the twelfth embodiment of the present invention.

  The optical drive waveform 2541 is composed of a plurality of pulses. Furthermore, the optical drive waveform 2541 has a drive start time of the first pulse delayed and a drive end time of the last pulse advanced with respect to the signal 2600 obtained by delaying the recording signal 2506 by a fixed amount K. .

  The delay amount is determined according to the length of a recording mark to be recorded, as shown in Table 12, taking (1, 7) modulation as an example.

  For example, since the length of the recording mark 2601 to be recorded is T2601 = 2 Tw (Tw is the detection window width), the recording start time is delayed by B12 (2), and the end time is ended only by E12 (2). Since the length of the recording mark 2602 to be recorded is T2602 = 8Tw, the recording start time is delayed by B12 (8), and the end time is ended only by E12 (8).

  The shorter the length of the mark to be recorded, the easier it is to obtain the rapid cooling condition at the beginning of the mark. In the case of a phase change medium that forms a mark by rapid cooling after temperature rise, the extension of the beginning of the mark is large. Therefore, there is a tendency that B12 (2)> B12 (3) >>...> B12 (8).

  The longer the mark length to be recorded, the greater the effect of heat accumulation at the end of the mark, and the greater the extension of the end. Therefore, there is a tendency that E12 (8)> E12 (7) >> ...> E12 (2).

  As a result, it is possible to correct the difference in the thermal history at the mark start end portion due to the recording mark length, and also to correct the difference in the heat accumulation at the mark end portion due to the recording mark length, so that the start end portion and the end portion of the recording marks 2601 and 2602 can be corrected. Is formed in the correct position.

  Note that the optical driving waveform 2541 is driven between the recording power and the erasing power here. However, if the driving is performed in accordance with the recording medium, such as between the recording power and the reproducing power, or between the recording power and 0. Good.

  FIG. 25 is a block diagram of a recording system of an optical disk device capable of obtaining an optical drive waveform according to Embodiment 12 of the present invention.

  25, reference numeral 2501 denotes a clock generation circuit, 2502 denotes a clock signal, 2503 denotes a recording signal generation circuit, 2504 denotes a recording signal output from the recording signal generation circuit 2503, 2505 denotes an H level period length measuring circuit, and 2506 denotes an H level period length. The recording signal after passing through the measurement circuit 2505, 2507 is the H level period measurement result output, 2508 is a pulse division circuit, 2509 is a top pulse, 2510 is an intermediate pulse, 2511 is a last pulse, 2512 is a first delay circuit, and 2513 is a first delay circuit. 1 memory, 2514 is a first memory output, 2515 is a first variable delay, 2516 is its output, 2517 is a second delay circuit, 2518 is a second memory, 2519 is a second memory output, and 2520 is a second variable delay , 2521 are its outputs, 2522 is a multi-pulse generation circuit, 2523 is an inversion circuit, 24 is an AND circuit, 2525 is an intermediate multipulse, 2526 is a fixed delay device, 2527 is its output, 2528 is a multipulse generation circuit, 2529 is an inversion circuit, 2530 is an AND circuit, 2531 is a last multipulse, 2532 is a selector, and 2533 is a selector. Is an output, 2534 is an OR circuit, 2535 is its output, 2536 is an AND circuit, 2537 is its output, 2538 is its selector, 2539 is its output, 2540 is a laser drive circuit, 2541 is an optical drive waveform, and 2542 is a gate generation circuit. , 2543 is its output, 2544 is a switch, and 2545 is a select signal. Here, the selectors 2532 and 2538 select and output the X input when the select signal 2545 is at the L level, and select and output the Y input when the select signal 2545 is at the H level.

  First, the operation when the switch 2544 is turned off, that is, when the select signal 2545 is at the L level, will be described with reference to the timing chart in FIG.

  The clock generation circuit 2501 outputs a channel clock 2502 whose cycle is the detection window width Tw. The duty is variable.

  The recording signal 2504 output from the recording signal generation circuit 2503 is input to the H level period length measurement circuit 2505 in synchronization with the rise of the channel clock signal 2502 from the clock generation circuit 2501.

  The H level period length measurement circuit 2505 measures the length of the H level period of the recording signal 2504, and outputs a recording signal 2506 and a measurement result 2507 again. The measurement result 2507 is output in synchronization with the rising of the measured H level of the recording signal 2506. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T2601 is 2, the measurement result 2507 becomes 2 at the rise of the H-level period T2601, and The length of T2602 is 8, and the measurement result 2507 becomes 8 at the rise of the H-level period T2602.

  Then, the measurement result 2507 is input to the first delay circuit 2512 and the second delay circuit 2517.

  In the first delay circuit 2512, the measurement result 2507 is input to the first memory 2513, and the first memory 2513 outputs the first memory output 2514. Here, as shown in Table 12, the first memory 2513 stores a value corresponding to the length of the current recording mark (corresponding to the measurement result 2507), and the corresponding stored value is output. .

  In the second delay circuit 2517, the measurement result 2507 is input to the second memory 2518, and the second memory 2518 outputs the second memory output 2519. Here, as shown in Table 12, the second memory 2518 stores a value corresponding to the length of the current recording mark (corresponding to the measurement result 2507), and the corresponding stored value is output. .

  On the other hand, the recording signal 2506 is divided into a leading pulse 2509, an intermediate pulse 2510, and a last pulse 2511 by a pulse dividing circuit 2508. In this example, the leading pulse 2509 rises at the rise of the recording signal 2506 and falls after Tw, and the intermediate pulse 2510 rises Tw after the rise of the recording signal 2506 and falls before Tw before the fall of the recording signal 2506. The last pulse 2511 is a signal which rises before Tw of the fall of the recording signal 2506 and falls at the fall of the recording signal 2506. When the H level period of the recording signal 2506 is 2 Tw, no intermediate pulse is generated.

  The first pulse 2509 is delayed by the first variable delay 2515 by the first memory output 2514 to become a signal 2516.

  The intermediate pulse 2510 is input to the multi-pulse generation circuit 2522, becomes an intermediate multi-pulse 2525, is delayed by a fixed delay unit 2526 having a delay amount K, and becomes a signal 2527.

  The last pulse 2511 becomes the last multi-pulse 2531 in the multi-pulse generation circuit 2528, is selected by the selector 2532, becomes the signal 2533, is delayed by the second variable delay 2520 according to the second memory output 2519, and becomes the signal 2521.

  The output 2535 of the signal 2516, the signal 2527, and the signal 2521 by the OR circuit 2534 is selected by the selector 2538, and is input to the laser driving circuit 2540, and the light source is driven to form the optical driving waveform 2541, and the recording marks 2601 and 2602 are formed. .

  Next, the case where the switch 2544 is ON will be described with reference to FIG.

  Gate generation circuit 2542 outputs an H level only when measurement result 2507 is 2. Therefore, when the measurement result 2507 is 2, the select signal 2545 becomes H level, and the selectors 2532 and 2538 select and output the Y input. Therefore, the last pulse 2511 is input to the second variable delay device 2520 and is delayed to be a signal 2521. Further, an output 2537 of the signal 2521 and the signal 2516 by the AND circuit 2536 is guided to the laser driving circuit 2540. Therefore, when the mark to be recorded is 2 Tw, a pulse width equal to or smaller than Tw can be created, and smaller marks can be handled.

  When the measurement result 2507 is other than 2, it is the same as when the switch 2544 is OFF.

  As described above, in the twelfth embodiment, when the recording mark 2601 or 2602 is formed, the recording mark 2601 or 2602 is driven by a plurality of pulses, and the driving start time of the first pulse is delayed according to the recording length of the recording mark. Since the difference in the thermal history of the mark start part due to the length of the recording mark is corrected, the end of the mark can be formed at the correct position, and the drive of the last pulse can be terminated early according to the length of the recording mark to be recorded. Thus, the difference in heat accumulation at the end of the mark due to the length of the recording mark is corrected, so that the end of the recording mark can also be formed at the correct position. Further, by driving in a plurality of pulses, the heat load applied to the medium can be reduced, and there is also an effect of reducing deterioration due to repeated recording.

  By changing the method of dividing the leading pulse, the intermediate pulse, and the last pulse by the pulse dividing circuit, various pulse patterns can be handled.

Here, the optical drive waveform is driven between the recording power and the erasing power, but it may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 13)
An optical drive waveform 2821 in FIG. 29 is an optical drive waveform according to the thirteenth embodiment of the present invention. In the optical drive waveform 2821, the drive start time at the recording power is delayed and the drive end time is earlier than the reference signal 2900 obtained by delaying the recording signal 2806 by a fixed amount K.

  The delay amount of the drive start time is determined according to the length of a recording mark to be recorded, as shown in Table 13 (a), in the case of (1, 7) modulation as an example.

  For example, since the length of the recording mark 2901 to be recorded is T2901 = 2 Tw (Tw is the detection window width), the driving start time of the recording power of the optical driving waveform 2821 is delayed by B13 (2), and the recording mark 2902 Since the length to be recorded is T2903 = 8Tw, the drive start time of the recording power of the optical drive waveform 2821 is delayed by B13 (8).

  In the case of the (1, 7) modulation, the delay amount of the drive end time is, as shown in Table 13 (b), a combination of the length of the recording mark to be recorded and the length of the immediately following non-recording portion. Is determined according to

  For example, the length of the recording mark 2901 to be recorded is T2901 = 2Tw (Tw is the detection window width), and the length of the non-recording portion immediately after is T2902 = 4Tw. Is completed earlier by E13 (2,4), the length of the recording mark 2902 to be recorded is T2903 = 8Tw, and the length of the non-recording portion immediately after is T2904 = 3Tw. The drive end time of the recording power of the optical drive waveform 2821 ends earlier by E13 (8, 3).

  The shorter the length of the mark to be recorded, the easier the quenching condition after the temperature rise at the mark start end is. Therefore, when the phase change medium is used, the extension of the mark start end increases. Therefore, there is a tendency that B13 (2)> B13 (3) >>...> B13 (8).

If the length of the unrecorded portion immediately after is the same, the longer the length of the mark to be recorded, the greater the effect of heat accumulation at the end of the mark and the greater the extension of the end. Therefore, there is a tendency that E13 (8, N)> E13 (7, N) >>...> E13 (2, N). (N is an integer from 2 to 8)
If the length of the mark to be recorded is the same, as the length of the non-recorded portion immediately after is shorter, the temperature of the mark end portion is less likely to decrease, and the end extension is larger. Therefore, there is a tendency that E13 (N, 2)> E13 (N, 3) >>...> E13 (N, 8). (N is an integer from 2 to 8)
As a result, the difference in the thermal history at the mark start end portion due to the recording mark length can be corrected, and the mark start end portion is formed at a correct position. Also, the difference in heat accumulation at the end of the mark due to the length of the recorded mark can be corrected, and the difference in the thermal history at the end of the mark due to the length of the immediately following unrecorded portion can be corrected. Is done.

  Note that here, the optical drive waveform 2821 is driven between the recording power and the erasing power, but if the driving is performed in accordance with the recording medium, such as between the recording power and the reproducing power, or between the recording power and 0. Good.

  FIG. 28 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to Embodiment 13 of the present invention.

  28, reference numeral 2801 denotes a clock generation circuit, 2802 denotes a clock signal, 2803 denotes a recording signal generation circuit, 2804 denotes a recording signal output from the recording signal generation circuit 2803, 2805 denotes an H level period length measurement circuit, and 2806 denotes an H level period length. The recording signal after passing through the measuring circuit 2805, 2807 is an H level period measurement result output, 2808 is a first delay circuit, 2809 is a first memory, 2810 is a first memory output, 2811 is a first variable delay device, and 2812 is a first variable delay device. Output, 2813 is a second delay circuit, 2814 is a second memory, 2815 is a second memory output, 2816 is a second variable delay, 2817 is its output, 2818 is an AND circuit, 2819 is its output, 2820 is a laser drive circuit , 2821 are optical drive waveforms, 2822 is an L level period length measurement circuit, and 2823 is the measurement result output. It is.

  The operation of the above configuration will be described with reference to the timing chart of FIG.

  The clock generation circuit 2801 outputs a channel clock 2802 whose cycle is the detection window width Tw. The duty is variable.

  The recording signal 2804 output from the recording signal generating circuit 2803 is input to the H level period length measuring circuit 2805 and the L level period length measuring circuit 2822 in synchronization with the rising of the channel clock signal 2802 from the clock generating circuit 2801. .

  An H level period length measuring circuit 2805 measures the length of the H level period of the recording signal 2804, and outputs a recording signal 2806 and a measurement result 2807 again. The measurement result 2807 is output in synchronization with the rise of the measured H level of the recording signal 2806. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T2901 is 2, the measurement result 2807 becomes 2 at the rise of the H-level period T2901, and The length of T2903 is 8, and the measurement result 2807 becomes 8 at the rise of the H-level period T2903.

  Then, the measurement result 2807 is input to the first delay circuit 2808 and the second delay circuit 2813.

  The L-level period length measurement circuit 2822 measures the length of the L-level period of the recording signal 2804, and outputs a measurement result 2823. The measurement result 2823 is output in synchronization with the rise of the H level immediately before the measured L level of the recording signal 2806. That is, if the length of the L-level period is represented by the number of channel clocks, the length of the L-level period T2902 is 4, and the measurement result 2823 is obtained at the rise of the H-level period T2901 immediately before the L-level period. 4 and the length of the L level period T2904 is 3, and the measurement result 2823 becomes 3 at the rise of the immediately preceding H level period T2903.

  Then, the measurement result 2823 is input to the second delay circuit 2813.

  In the first delay circuit 2808, the measurement result 2807 is input to the first memory 2809, and the first memory 2809 outputs the first memory output 2810. Here, as shown in Table 13 (a), a value corresponding to the length of the current recording mark (corresponding to the measurement result 2807) is stored in the memory 2809, and the corresponding stored value is output. You. The first variable delay unit 2811 delays the recording signal 2806 and outputs a signal 2812 according to the first memory output 2810.

  In the second delay circuit 2813, the measurement results 2807 and 2823 are input to the second memory 2814, and the second memory 2814 outputs a second memory output 2815. Here, as shown in Table 13 (b), the second memory 2814 stores the length of the current recording mark (corresponding to the measurement result 2807) and the length of the immediately non-recorded portion (corresponding to the measurement result 2823). And the corresponding stored value is stored, and the corresponding stored value is output. The second variable delay 2816 delays the recording signal 2806 according to the second memory output 2815 and outputs a signal 2817.

  The signal 2812 and the signal 2817 are input to an AND circuit 2818 and output as a signal 2819.

  The output signal 2819 is input to the laser driving circuit 2820, and the light source is driven to form an optical driving waveform 2821, and recording marks 2901 and 2902 are formed.

  As described above, in the thirteenth embodiment, when forming the recording marks 2901 and 2902, the drive start time at the recording power is delayed according to the recording length of the recording marks, and the recording start time depends on the length of the recording marks. Since the difference in the thermal history at the mark start end is corrected, the start end of the recording mark can be formed at a correct position. In addition, according to the combination of the length of the recording mark to be recorded and the length of the non-recording portion immediately after, the drive end time at the recording power is ended earlier, and the heat at the end of the mark due to the length of the recording mark is shortened. Since the difference in the accumulation is corrected and the difference in the thermal history at the end of the mark due to the length of the non-recorded portion immediately after is corrected, the end of the recorded mark can be formed at the correct position.

Here, the optical drive waveform is driven between the recording power and the erasing power, but it may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 14)
An optical drive waveform 3041 in FIG. 31 is an optical drive waveform according to the fourteenth embodiment of the present invention.

  The optical drive waveform 3041 is composed of a plurality of pulses. Further, with respect to the optical drive waveform 3041, the drive start time of the first pulse is delayed and the drive end time of the last pulse is earlier with respect to the signal 3100 obtained by delaying the recording signal 3006 by a fixed amount K. .

  The drive start delay amount of the first pulse is determined according to the length of a recording mark to be recorded, as shown in Table 14 (a), using (1, 7) modulation as an example.

  For example, since the recording length of the recording mark 3101 is T3101 = 2 Tw (Tw is the detection window width), the recording start time is delayed by B14 (2), and the recording length of the recording mark 3102 is T3103 = 2. Since it is 8Tw, the recording start time is delayed by B14 (8).

  The drive end delay amount of the last pulse is, as shown in Table 14 (b), taking the length of the recording mark to be recorded and the length of the non-recording portion immediately after, as shown in Table 14 (b), in the case of (1, 7) modulation. Is determined according to the combination of

  For example, the length of the recording mark 3101 to be recorded is T3101 = 2 Tw (Tw is the detection window width), and the length of the immediately non-recorded portion is T3102 = 4 Tw, so the end time is E14 (2, 4), the length of the recording mark 3102 to be recorded is T3103 = 8Tw, and the length of the non-recording portion immediately after is T3104 = 3Tw, so the end time is only E14 (8,3). Be quick.

  The shorter the length of the mark to be recorded, the easier it is to obtain the rapid cooling condition at the beginning of the mark. In the case of a phase change medium that forms a mark by rapid cooling after temperature rise, the extension of the beginning of the mark is large. Therefore, there is a tendency that B14 (2)> B14 (3) >>...> B14 (8).

  If the length of the unrecorded portion immediately after is the same, the longer the length of the mark to be recorded, the greater the effect of heat accumulation at the end of the mark and the greater the extension of the end. Therefore, there is a tendency that E14 (8, N)> E14 (7, N) >>...> E14 (2, N) (N is an integer of 2 to 8).

  If the length of the mark to be recorded is the same, the shorter the length of the non-recorded portion immediately after, the more difficult it is for the temperature at the end portion of the mark to decrease, and the larger the extension of the end portion. Therefore, there is a tendency that E14 (N, 2)> E14 (N, 3) >>...> E14 (N, 8) (N is an integer of 2 to 8).

  As a result, it is possible to correct the difference in the thermal history at the mark start end portion due to the recording mark length, and also to correct the difference in the heat accumulation at the mark end portion due to the recording mark length. Can be corrected, the start and end portions of the recording marks 3101 and 3102 are formed at the correct positions.

  Note that here, the optical drive waveform 3041 is driven between the recording power and the erasing power, but if the driving is performed in accordance with the recording medium, such as between the recording power and the reproducing power or between the recording power and 0. Good.

  FIG. 30 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to Embodiment 14 of the present invention.

  30, 3001 is a clock generation circuit, 3002 is a clock signal, 3003 is a recording signal generation circuit, 3004 is a recording signal output from the recording signal generation circuit 3003, 3005 is an H level period length measurement circuit, and 3006 is an H level period length. The recording signal after passing through the measurement circuit 3005, 3007 is an H level period measurement result output, 3008 is a pulse division circuit, 3009 is a top pulse, 3010 is an intermediate pulse, 3011 is a last pulse, 3012 is a first delay circuit, and 3013 is a first delay circuit. 1 memory, 3014 is a first memory output, 3015 is a first variable delay, 3016 is its output, 3017 is a second delay circuit, 3018 is a second memory, 3019 is a second memory output, 3020 is a second variable delay , 3021 are its outputs, 3022 is a multi-pulse generation circuit, 3023 is an inversion circuit, 24 is an AND circuit, 3025 is an intermediate multipulse, 3026 is a fixed delay unit, 3027 is its output, 3028 is a multipulse generating circuit, 3029 is an inverting circuit, 3030 is an AND circuit, 3031 is a last multipulse, 3032 is a selector, 3033 Is an output, 3034 is an OR circuit, 3035 is its output, 3036 is an AND circuit, 3037 is its output, 3038 is its selector, 3039 is its output, 3040 is a laser drive circuit, 3041 is a light drive waveform, and 3042 is a gate generation circuit , 3043 are its output, 3044 is a switch, and 3045 is a select signal. Here, the selectors 3032 and 3038 select and output the X input when the select signal 3045 is at the L level, and select and output the Y input when the select signal 3045 is at the H level. Reference numeral 3046 denotes an L-level period length detection circuit, and reference numeral 3047 denotes an output of the measurement result.

  First, the operation when the switch 3044 is off, that is, when the select signal 3045 is at the L level, will be described with reference to the timing chart of FIG.

  The clock generation circuit 3001 outputs a channel clock 3002 whose cycle is the detection window width Tw. The duty is variable.

  The recording signal 3004 output from the recording signal generation circuit 3003 is input to the H level period length measurement circuit 3005 and the L level period length measurement circuit 3046 in synchronization with the rising of the channel clock signal 3002 from the clock generation circuit 3001. .

  The H level period length measurement circuit 3005 measures the length of the H level period of the recording signal 3004, and outputs a recording signal 3006 and a measurement result 3007 again. The measurement result 3007 is output in synchronization with the measured rise of the H level of the recording signal 3006. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T3101 is 2, and the measurement result 3007 becomes 2 at the rise of the H-level period T3101. The length of T3103 is 8, and the measurement result 3007 becomes 8 at the rise of the H-level period T3103.

  Then, the measurement result 3007 is input to the first delay circuit 3012 and the second delay circuit 3017.

  The L-level period length measuring circuit 3046 measures the length of the L-level period of the recording signal 3004, and outputs a measurement result 3047. The measurement result 3047 is output in synchronization with the rising of the H level immediately before the measured L level of the recording signal 3006. That is, if the length of the L level period is represented by the number of channel clocks, the length of the L level period T3102 is 4, and the measurement result 3047 becomes 4 at the rise of the H level period T3101 immediately before the L level. , L level period T3104 has a length of 3, and the measurement result 3047 becomes 3 at the rising edge of the immediately preceding H level period T3103.

  Then, the measurement result 3047 is input to the second delay circuit 3017.

  In the first delay circuit 3012, the measurement result 3007 is input to the first memory 3013, and the first memory 3013 outputs the first memory output 3014. Here, in the first memory 3013, as shown in Table 14 (a), a value corresponding to the length of the current recording mark (corresponding to the measurement result 3007) is stored. Is output.

  In the second delay circuit 3017, the measurement results 3007 and 3047 are input to a second memory 3018, and a second memory output 3019 is output from the second memory 3018. Here, as shown in Table 14 (b), in the second memory 3018, the length of the current recording mark (corresponding to the measurement result 3007) and the length of the immediately non-recorded portion (corresponding to the measurement result 3047) are stored. The value is stored corresponding to the combination of (correspondence), and the corresponding stored value is output.

  On the other hand, the recording signal 3006 is divided by a pulse dividing circuit 3008 into a leading pulse 3009, an intermediate pulse 3010, and a last pulse 3011. In this example, the first pulse 3009 rises at the rise of the recording signal 3006 and falls after Tw, and the intermediate pulse 3010 rises Tw after the rise of the recording signal 3006 and falls Tw before the fall of the recording signal 3006. The last pulse 3011 is a signal that rises before Tw of the fall of the recording signal 3006 and falls at the fall of the recording signal 3006. When the H level period of the recording signal 3006 is 2 Tw, no intermediate pulse is generated.

  The first pulse 3009 is delayed by the first variable delay 3015 by the first memory output 3014 to become a signal 3016.

  The intermediate pulse 3010 is input to a multi-pulse generation circuit 3022, becomes an intermediate multi-pulse 3025, is delayed by a fixed delay unit 3026 having a delay amount K, and becomes a signal 3027.

  The last pulse 3011 becomes the last multipulse 3031 in the multipulse generation circuit 3028, is selected by the selector 3032, becomes a signal 3033, is delayed by the second variable delay 3020 according to the second memory output 3019, and becomes the signal 3021.

  The output 3035 of the signal 3016, the signal 3027, and the signal 3021 by the OR circuit 3034 is selected by the selector 3038, and is input to the laser driving circuit 3040. The light source is driven, and the light driving waveform 3041 is formed, and the recording marks 3101 and 3102 are formed. .

  Next, the case where the switch 3044 is ON will be described with reference to FIG.

  Gate generation circuit 3042 outputs an H level only when measurement result 3007 is 2. Therefore, the select signal 3045 becomes H level when the measurement result 3007 is 2, and the selectors 3032 and 3038 select and output the Y input. Therefore, the last pulse 3011 is input to the second variable delay device 3020 and is delayed to become the signal 3021, and the output 3037 of the signal 3021 and the signal 3016 by the AND circuit 3036 is guided to the laser driving circuit 3040. Therefore, when the mark to be recorded is 2 Tw, a pulse width equal to or smaller than Tw can be created, and smaller marks can be handled.

  When the measurement result 3007 is other than 2, it is the same as when the switch 3044 is OFF.

  As described above, in the fourteenth embodiment, when forming the recording mark 3101 or 3102, the recording mark 3101 or 3102 is driven by a plurality of pulses, and the driving start time of the first pulse is delayed according to the length of the recording mark to be recorded. Corrects the difference in the thermal history of the mark start end due to the length of the recording mark, so that the end of the mark can be formed at the correct position, and the combination of the length of the recording mark to be recorded and the length of the non-recording portion immediately after Accordingly, the driving of the last pulse is terminated early to correct the difference in heat accumulation at the end of the mark due to the length of the recording mark and the difference in the thermal history at the end of the mark due to the length of the non-recording portion immediately after. Also, the end portion of the recording mark can be formed at a correct position. Further, by driving in a plurality of pulses, the heat load applied to the medium can be reduced, and there is also an effect of reducing deterioration due to repeated recording.

  By changing the method of dividing the leading pulse, the intermediate pulse, and the last pulse by the pulse dividing circuit, various pulse patterns can be handled.

Here, the optical drive waveform is driven between the recording power and the erasing power, but it may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 15)
An optical drive waveform 3321 in FIG. 34 is an optical drive waveform in the fifteenth embodiment of the present invention. In the optical drive waveform 3321, the drive start time at the recording power is delayed and the drive end time is earlier than the reference signal 3400 obtained by delaying the recording signal 3306 by a fixed amount K.

  In the case of the (1, 7) modulation as an example, the delay amount of the drive start time is, as shown in Table 15 (a), a combination of the length of the recording mark to be recorded and the length of the immediately preceding non-recording portion. Is determined according to

  For example, the length of the non-recording portion immediately before the recording mark 3401 should be T3401 = 3Tw, and the length to be recorded is T3402 = 2Tw (Tw is the detection window width). Is delayed by B15 (3,2), the length of the non-recording portion immediately before the recording mark 3402 should be T3403 = 4Tw, and the length to be recorded is T3404 = 8Tw. The drive start time of the recording power of the drive waveform 3321 is delayed by B15 (4, 8).

  The delay amount of the drive end time is determined according to the length of a recording mark to be recorded, as shown in Table 15 (b), in the case of (1, 7) modulation as an example.

  For example, the recording length of the recording mark 3401 is T3402 = 2Tw (Tw is the detection window width), so that the driving end time of the recording power of the optical driving waveform 3321 ends earlier by E15 (2), and the recording mark 3402 Is to be recorded, the driving end time of the recording power of the optical driving waveform 3321 ends earlier by E15 (8).

  If the length of the mark to be recorded is the same, the shorter the desired length of the immediately preceding non-recorded portion, the greater the thermal effect of the previous recording power on the current mark start end, and the longer the mark start end. Therefore, there is a tendency that B15 (2, N)> B15 (3, N) >> ... B15 (8, N) (N is an integer of 2 to 8).

  If the length of the immediately preceding unrecorded portion is the same, the shorter the length of the mark to be recorded, the easier it is to obtain the quenching condition after the temperature rise at the beginning of the mark. The elongation at the starting end increases. Therefore, there is a tendency that B15 (N, 2)> B15 (N, 3) >>...> B15 (N, 8) (N is an integer of 2 to 8).

  The longer the mark length to be recorded, the greater the effect of heat accumulation at the end of the mark, and the greater the extension of the end. Therefore, there is a tendency that E15 (8)> E15 (7) >>...> E15 (2).

  As a result, it is possible to correct the difference in the thermal effect of the previous recording power at the beginning of the mark due to the length of the previous non-recorded portion and the difference in the thermal history at the beginning of the mark due to the length of the recording mark. It is formed. Also, since the difference in heat accumulation at the mark end portion due to the recording mark length can be corrected, the mark end portion is formed at a correct position.

  Note that here, the optical drive waveform 3321 is driven between the recording power and the erasing power, but if it is driven in accordance with the recording medium, such as between the recording power and the reproducing power or between the recording power and 0. Good.

  FIG. 33 is a block diagram of a recording system of an optical disk device capable of obtaining an optical drive waveform according to Embodiment 15 of the present invention.

  33, reference numeral 3301 denotes a clock generation circuit, 3302 denotes a clock signal, 3303 denotes a recording signal generation circuit, 3304 denotes a recording signal output from the recording signal generation circuit 3303, 3305 denotes an H level period length measuring circuit, and 3306 denotes an H level period length. The recording signal after passing through the measurement circuit 3305, 3307 is an H level period measurement result output, 3308 is a first delay circuit, 3309 is a first memory, 3310 is a first memory output, 3311 is a first variable delay device, and 3312 is a Output, 3313 is a second delay circuit, 3314 is a second memory, 3315 is a second memory output, 3316 is a second variable delay, 3317 is its output, 3318 is an AND circuit, 3319 is its output, 3320 is a laser drive circuit , 3321 are optical drive waveforms, 3322 is an L level period length measurement circuit, and 3323 is the measurement result output. It is.

  The operation of the above configuration will be described with reference to the timing chart of FIG.

  The clock generation circuit 3301 outputs a channel clock 3302 whose cycle is the detection window width Tw. The duty is variable.

  The recording signal 3304 output from the recording signal generation circuit 3303 is input to the H level period length measurement circuit 3305 and the L level period length measurement circuit 3322 in synchronization with the rising of the channel clock signal 3302 from the clock generation circuit 3301. .

  The H level period length measuring circuit 3305 measures the length of the H level period of the recording signal 3304, and outputs a recording signal 3306 and a measurement result 3307 again. The measurement result 3307 is output in synchronization with the rising of the measured H level of the recording signal 3306. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T3402 is 2, and the measurement result 3307 becomes 2 at the rise of the H-level period T3402. The length of T3404 is 8, and the measurement result 3307 becomes 8 at the rise of the H-level period T3404.

  Then, the measurement result 3307 is input to the first delay circuit 3308 and the second delay circuit 3313.

  The L-level period length measuring circuit 3322 measures the length of the L-level period of the recording signal 3304, and outputs a measurement result 3323. The measurement result 3323 is output in synchronization with the rise of the H level immediately after the measured L level of the recording signal 3306. That is, if the length of the L-level period is represented by the number of channel clocks, the length of the L-level period T3401 is 3, and the measurement result 3323 is obtained at the rise of the H-level period T3402 immediately after the L-level period. 3, the length of the L-level period T3403 is 4, and the measurement result 3323 is 4 at the rise of the H-level period T3404 immediately after.

  Then, the measurement result 3323 is input to the first delay circuit 3308.

  In the first delay circuit 3308, the measurement results 3307 and 3323 are input to a first memory 3309, and the first memory 3309 outputs a first memory output 3310. Here, in the memory 3309, as shown in Table 15 (a), the length of the immediately preceding non-recording portion (corresponding to the measurement result 3323) and the length of the current recording mark (corresponding to the measurement result 3307) Are stored in correspondence with the combination of, and the corresponding stored value is output. The first variable delay unit 3311 delays the recording signal 3306 and outputs a signal 3312 according to the first memory output 3310.

  Further, in the second delay circuit 3313, the measurement result 3307 is input to the second memory 3314, and the second memory output 3315 is output from the second memory 3314. Here, as shown in Table 15 (b), the second memory 3314 stores a value corresponding to the length of the current recording mark (corresponding to the measurement result 3307). Is output. The second variable delay unit 3316 delays the recording signal 3306 according to the second memory output 3315 and outputs a signal 3317.

  The signal 3312 and the signal 3317 are input to an AND circuit 3318 and output as a signal 3319.

  The output signal 3319 is input to the laser driving circuit 3320, and the light source is driven to generate an optical driving waveform 3321, and recording marks 3401 and 3402 are formed.

  As described above, in the fifteenth embodiment, when the recording marks 3401 and 3402 are formed, the recording power is changed according to the combination of the length of the previous non-recording portion and the length of the current recording mark. The drive start time is delayed to compensate for the difference in thermal effect at the mark start end due to the length of the previous non-recorded portion and the difference in the thermal history at the mark start end due to the length of the current record mark. Can be formed at the correct position. In addition, the drive end time at the recording power is ended earlier according to the length of the recording mark to be recorded, and the difference in heat accumulation at the end of the mark due to the length of the recording mark is corrected. The part can be formed in the correct position.

Here, the optical drive waveform is driven between the recording power and the erasing power, but it may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 16)
An optical drive waveform 3541 in FIG. 36 is an optical drive waveform in the sixteenth embodiment of the present invention.

  The optical drive waveform 3541 is composed of a plurality of pulses. Furthermore, the optical drive waveform 3541 has a drive start time of the first pulse delayed and a drive end time of the last pulse advanced with respect to the signal 3600 obtained by delaying the recording signal 3506 by a fixed amount K. .

  The drive start delay amount of the first pulse is, as shown in Table 16 (a), when the (1, 7) modulation is taken as an example, as shown in Table 16 (a), the length of the immediately preceding non-recording portion and the length of the recording mark to be recorded. Is determined according to the combination of

  For example, the desired length of the non-recording portion immediately before the recording mark 3601 is T3601 = 2Tw, and the length to be recorded is T3602 = 2Tw (Tw is the detection window width), so that the recording start time is B16 (2 , 2), the desired length of the non-recording portion immediately before the recording mark 3602 is T3603 = 4Tw, and the length to be recorded is T3604 = 8Tw. Therefore, the recording start time is B16 (4,8). A) delay.

  The drive end delay amount of the last pulse is determined according to the length of a recording mark to be recorded, as shown in Table 16 (b), taking (1, 7) modulation as an example.

  For example, since the recording length of the recording mark 3601 is T3602 = 2 Tw (Tw is the detection window width), the end time is earlier by E16 (2), and the recording length of the recording mark 3602 is T3604 = 8 Tw. Therefore, the end time is advanced by E16 (8).

  If the length of the mark to be recorded is the same, the shorter the length of the immediately preceding non-recording portion, the greater the thermal effect of the previous recording power on the beginning of the current recording mark, and the greater the extension of the mark beginning. Therefore, there is a tendency that B16 (2, N)> B16 (3, N) >> ... B16 (8, N) (N is an integer of 2 to 8).

  If the length of the previous unrecorded portion is the same, the shorter the length of the mark to be recorded, the easier it is to obtain the quenching condition at the beginning of the mark, and in the case of a phase change medium that forms a mark by quenching after heating. Has a large extension at the mark start end. Therefore, there is a tendency that B16 (N, 2)> B14 (N, 3) >>...> B14 (N, 8).

  The longer the mark length to be recorded, the greater the effect of heat accumulation at the end of the mark, and the greater the extension of the end. Therefore, there is a tendency that E16 (8)> E16 (7) >>...> E16 (2) (N is an integer of 2 to 8).

  As a result, it is possible to correct the difference in the thermal effect at the mark start end due to the length of the immediately preceding non-recorded portion and the difference in the thermal history at the mark start end due to the record mark length, and the heat accumulation at the mark end due to the record mark length. Since the difference can be corrected, the start and end portions of the recording marks 3601 and 3602 are formed at correct positions.

  Note that the optical driving waveform 3541 is driven between the recording power and the erasing power here. However, if the driving is performed in accordance with the recording medium, such as between the recording power and the reproducing power, or between the recording power and 0. Good.

  FIG. 35 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to Embodiment 16 of the present invention.

  In FIG. 35, reference numeral 3501 denotes a clock generation circuit, 3502 denotes a clock signal, 3503 denotes a recording signal generation circuit, 3504 denotes a recording signal output from the recording signal generation circuit 3503, 3505 denotes an H level period length measuring circuit, and 3506 denotes an H level period length. The recording signal after passing through the measuring circuit 3505, 3507 is an H level period measurement result output, 3508 is a pulse dividing circuit, 3509 is a leading pulse, 3510 is an intermediate pulse, 3511 is a last pulse, 3512 is a first delay circuit, and 3513 is a 1 memory, 3514 is a first memory output, 3515 is a first variable delay, 3516 is its output, 3517 is a second delay circuit, 3518 is a second memory, 3519 is a second memory output, 3520 is a second variable delay , 3521 are its outputs, 3522 is a multi-pulse generation circuit, 3523 is an inversion circuit, 24 is an AND circuit, 3525 is an intermediate multipulse, 3526 is a fixed delay, 3527 is its output, 3528 is a multipulse generation circuit, 3529 is an inversion circuit, 3530 is an AND circuit, 3531 is last multipulse, 3532 is a selector, 3533 Is an output thereof, 3534 is an OR circuit, 3535 is an output thereof, 3536 is an AND circuit thereof, 3537 is an output thereof, 3538 is a selector thereof, 3538 is an output thereof, 3540 is a laser driving circuit, 3541 is a light driving waveform, and 3542 is a gate generating circuit. , 3543 are its output, 3544 is a switch, and 3545 is a select signal. Here, the selectors 3532 and 3538 select and output the X input when the select signal 3545 is at the L level, and select and output the Y input when the select signal 3545 is at the H level. Further, reference numeral 3546 denotes an L-level period length detection circuit, and reference numeral 3547 denotes an output of the measurement result.

  First, the operation when the switch 3544 is turned off, that is, when the select signal 3545 is at the L level is described with reference to a timing chart in FIG.

  The clock generation circuit 3501 outputs a channel clock 3502 whose cycle is the detection window width Tw. The duty is variable.

  The recording signal 3504 output from the recording signal generation circuit 3503 is input to the H-level period length measurement circuit 3505 and the L-level period length measurement circuit 3546 in synchronization with the rise of the channel clock signal 3502 from the clock generation circuit 3501. .

  An H level period length measuring circuit 3505 measures the length of the H level period of the recording signal 3504, and outputs a recording signal 3506 and a measurement result 3507 again. The measurement result 3507 is output in synchronization with the measured rise of the H level of the recording signal 3506. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T3602 is 2, and the measurement result 3507 becomes 2 at the rise of the H-level period T3602. The length of T3604 is 8, and the measurement result 3507 becomes 8 at the rise of the H-level period T3604.

  Then, the measurement result 3507 is input to the first delay circuit 3512 and the second delay circuit 3517.

  The L level period length measuring circuit 3546 measures the length of the L level period of the recording signal 3504, and outputs a measurement result 3547. The measurement result 3547 is output in synchronization with the rising of the H level immediately after the measured L level of the recording signal 3506. That is, if the length of the L-level period is represented by the number of channel clocks, the length of the L-level period T3601 is 2, and the measurement result 3547 becomes 2 at the rise of the H-level period T3602 immediately after the L level. , The length of the L-level period T3603 is 4, and the measurement result 3547 becomes 4 at the rise of the immediately subsequent H-level period T3604.

  Then, the measurement result 3547 is input to the first delay circuit 3512.

  In the first delay circuit 3512, the measurement results 3507 and 3547 are input to a first memory 3513, and the first memory 3513 outputs a first memory output 3514. Here, in the first memory 3513, as shown in Table 16 (a), the length of the immediately preceding unrecorded portion (corresponding to the measurement result 3547) and the length of the current recording mark (corresponding to the measurement result 3507) are stored. And the corresponding stored value is stored, and the corresponding stored value is output.

  In the second delay circuit 3517, the measurement result 3507 is input to the second memory 3518, and the second memory 3518 outputs the second memory output 3519. Here, as shown in Table 16 (b), in the second memory 3518, a value corresponding to the length of the current recording mark (corresponding to the measurement result 3007) is stored, and the corresponding stored value is stored. Is output.

  On the other hand, the recording signal 3506 is divided by a pulse dividing circuit 3508 into a leading pulse 3509, an intermediate pulse 3510, and a last pulse 3511. In this example, the leading pulse 3509 rises at the rise of the recording signal 3506 and falls after Tw, and the intermediate pulse 3510 rises Tw after the rise of the recording signal 3506 and falls Tw before the fall of the recording signal 3506. The last pulse 3511 is a signal that rises Tw before the fall of the recording signal 3506 and falls at the fall of the recording signal 3506. When the H level period of the recording signal 3506 is 2 Tw, no intermediate pulse is generated.

  The first pulse 3509 is delayed by the first variable delay 3515 by the first memory output 3514 to become a signal 3516.

  The intermediate pulse 3510 is input to the multi-pulse generation circuit 3522, becomes an intermediate multi-pulse 3525, is delayed by a fixed delay unit 3526 having a delay amount K, and becomes a signal 3527.

  The last pulse 3511 becomes the last multi-pulse 3531 in the multi-pulse generation circuit 3528, is selected by the selector 3532, becomes the signal 3533, is delayed by the second variable delay 3520 according to the second memory output 3519, and becomes the signal 3521.

  An output 3535 of an OR circuit 3534 of the signal 3516, the signal 3527, and the signal 3521 is selected by the selector 3538, and is input to the laser driving circuit 3540, and the light source is driven to be an optical driving waveform 3541, and recording marks 3601 and 3602 are formed. .

  Next, the case where the switch 3544 is ON will be described with reference to FIG.

  Gate generation circuit 3542 outputs an H level only when measurement result 3507 is 2. Therefore, the select signal 3545 becomes H level when the measurement result 3507 is 2, and the selectors 3532 and 3538 select and output the Y input. Therefore, the last pulse 3511 is input to the second variable delay unit 3520 and is delayed to become a signal 3521. Further, an output 3537 of the signal 3521 and the signal 3516 by the AND circuit 3536 is guided to the laser driving circuit 3540. Therefore, when the mark to be recorded is 2 Tw, a pulse width equal to or smaller than Tw can be created, and smaller marks can be handled.

  When the measurement result 3507 is other than 2, it is the same as when the switch 3544 is OFF.

  As described above, in the sixteenth embodiment, when the recording mark 3601 or 3602 is formed, the recording mark 3601 or 3602 is driven by a plurality of pulses, and the recording mark 3601 or 3602 is driven according to the combination of the length of the immediately preceding non-recording portion and the length of the recording mark. Since the drive start time of the first pulse is delayed to compensate for the difference in the thermal effect of the previous recording power due to the length of the immediately preceding non-recording portion and the difference in the thermal history at the start of the mark due to the length of the recording mark, the mark The end of the mark can be formed at the correct position, and the drive of the last pulse is terminated early according to the length of the recording mark to be recorded, thereby correcting the difference in heat accumulation at the mark end due to the length of the recording mark. Therefore, the end portion of the recording mark can also be formed at a correct position. Further, by driving in a plurality of pulses, the heat load applied to the medium can be reduced, and there is also an effect of reducing deterioration due to repeated recording.

  By changing the method of dividing the leading pulse, the intermediate pulse, and the last pulse by the pulse dividing circuit, various pulse patterns can be handled.

Here, the optical drive waveform is driven between the recording power and the erasing power, but it may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 17)
An optical drive waveform 3821 in FIG. 39 is an optical drive waveform in the seventeenth embodiment of the present invention. In the optical drive waveform 3821, the drive start time at the recording power is delayed and the drive end time is earlier than the reference signal 3900 obtained by delaying the recording signal 3806 by a fixed amount K.

  In the case of the (1, 7) modulation as an example, the delay amount of the drive start time is, as shown in Table 17 (a), a combination of the length of the recording mark to be recorded and the length of the immediately preceding non-recording portion. Is determined according to

  For example, the length of the non-recording portion immediately before the recording mark 3901 should be T3901 = 2Tw, and the length to be recorded is T3902 = 2Tw (Tw is the detection window width). Is delayed by B17 (2, 2), the length of the non-recording portion immediately before the recording mark 3902 should be T3903 = 4Tw, and the length to be recorded is T3904 = 8Tw. The drive start time of the recording power of the drive waveform 3821 is delayed by B17 (4, 8).

  In the case of the (1, 7) modulation as an example, the delay amount of the drive end time is, as shown in Table 17 (b), a combination of the length of the recording mark to be recorded and the length of the immediately following non-recording portion. Is determined according to

  For example, the length of the recording mark 3901 to be recorded is T3902 = 2 Tw (Tw is the detection window width), and the length of the non-recording portion immediately after is T3903 = 4 Tw. Is completed earlier by E17 (2, 4), the recording length of the recording mark 3902 is T3904 = 8Tw, and the length of the non-recording portion immediately after is T3905 = 3Tw. The drive end time of the recording power of the optical drive waveform 3821 ends earlier by E17 (8, 3).

  If the length of the mark to be recorded is the same, the shorter the desired length of the immediately preceding non-recorded portion, the greater the thermal effect of the previous recording power on the current mark start end, and the longer the mark start end. Therefore, there is a tendency that B17 (2, N)> B17 (3, N) >> ...> B17 (8, N) (N is an integer of 2 to 8).

  If the length of the immediately preceding unrecorded portion is the same, the shorter the length of the mark to be recorded, the easier it is to obtain the quenching condition after the temperature rise at the beginning of the mark. The elongation at the starting end increases. Therefore, there is a tendency that B17 (N, 2)> B17 (N, 3) >>...> B17 (N, 8) (N is an integer of 2 to 8).

  If the length of the immediately following unrecorded portion is the same, the longer the mark length to be recorded, the greater the effect of heat accumulation at the end portion of the mark and the greater the extension of the end portion. Therefore, there is a tendency that E17 (8, N)> E17 (7, N) >>...> E17 (2, N) (N is an integer of 2 to 8).

If the length of the mark to be recorded is the same, the shorter the length of the immediately unrecorded portion, the more difficult it is for the temperature at the end portion of the mark to decrease, and the greater the extension of the end portion. Therefore,
E17 (N, 2)> E17 (N, 3) >>...> E17 (N, 8) (N is an integer from 2 to 8).

  As a result, the difference in the thermal effect of the previous recording power at the start of the mark due to the length of the immediately preceding non-recorded portion and the difference in the thermal history at the start of the mark due to the recording mark length can be corrected. Formed. In addition, since the difference in heat accumulation at the end of the mark due to the length of the recording mark and the difference in the thermal history at the end of the mark due to the length of the non-recorded portion immediately after can be corrected, the end of the mark is formed at the correct position.

  Note that the optical driving waveform 3821 is driven between the recording power and the erasing power here. However, if the optical driving waveform 3821 is driven according to the recording medium, such as between the recording power and the reproducing power, or between the recording power and 0. Good.

  FIG. 38 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to Embodiment 17 of the present invention.

  38, reference numeral 3801 denotes a clock generation circuit, 3802 denotes a clock signal, 3803 denotes a recording signal generation circuit, 3804 denotes a recording signal output from the recording signal generation circuit 3803, 3805 denotes an H level period length measuring circuit, and 3806 denotes an H level period length. The recording signal after passing through the measurement circuit 3805, 3807 is an H level period measurement result output, 3808 is a first delay circuit, 3809 is a first memory, 3810 is a first memory output, 3811 is a first variable delay, and 3812 is Output, 3813 is a second delay circuit, 3814 is a second memory, 3815 is a second memory output, 3816 is a second variable delay, 3817 is its output, 3818 is an AND circuit, 3819 is its output, 3820 is a laser drive circuit , 3821 is the optical drive waveform, 3822 is the L level period length measurement circuit 1, 3823 is the measurement result Force, 3824 L-level period length measurement circuit 2,3825 is the measurement result output.

  The operation of the above configuration will be described with reference to the timing chart of FIG.

  The clock generation circuit 3801 outputs a channel clock 3802 having a cycle of the detection window width Tw. The duty is variable.

  In synchronization with the rise of the channel clock signal 3802 from the clock generation circuit 3801, the recording signal 3804 output from the recording signal generation circuit 3803 is supplied to the H level period length measurement circuit 3805 and the L level period length measurement circuit 1 (3822). It is input to the L-level period length measurement circuit 2 (3824).

  The L level period length measurement circuit 1 (3822) measures the length of the L level period of the recording signal 3804, and outputs a measurement result 3823. The measurement result 3823 is output in synchronization with the rising of the H level immediately after the measured L level of the recording signal 3806. That is, if the length of the L-level period is represented by the number of channel clocks, the length of the L-level period T3901 is 2, and the measurement result 3823 is obtained at the rise of the H-level period T3902 immediately after the L-level period. 2 and the length of the L-level period T3903 is 4, and the measurement result 3823 becomes 4 at the rise of the H-level period T3904 immediately after.

  Then, the measurement result 3823 is input to the first delay circuit 3808.

  An H level period length measuring circuit 3805 measures the length of the H level period of the recording signal 3804, and outputs a recording signal 3806 and a measurement result 3807 again. The measurement result 3807 is output in synchronization with the rise of the measured H level of the recording signal 3806. That is, if the length of the H-level period is represented by the number of channel clocks, the length of the H-level period T3902 is 2, and the measurement result 3807 becomes 2 at the rise of the H-level period T3902. The length of T3904 is 8, and the measurement result 3807 becomes 8 at the rise of the H-level period T3904.

  Then, the measurement result 3807 is input to the first delay circuit 3808 and the second delay circuit 3813.

  The L level period length measurement circuit 2 (3824) measures the length of the L level period of the recording signal 3804, and outputs a measurement result 3825. The measurement result 3825 is output in synchronization with the rising of the H level immediately before the measured L level of the recording signal 3806. That is, if the length of the L-level period is represented by the number of channel clocks, the length of the L-level period T3903 is 4, and the measurement result 3825 is obtained at the rise of the H-level period T3902 immediately before the L-level period. 4 and the length of the L level period T3905 is 3, and the measurement result 3825 becomes 3 at the rise of the H level period T3904 immediately after.

  Then, the measurement result 3825 is input to the second delay circuit 3813.

  In the first delay circuit 3808, the measurement results 3807 and 3823 are input to a first memory 3809, and the first memory 3809 outputs a first memory output 3810. Here, as shown in Table 17 (a), the first memory 3809 stores the length of the immediately preceding unrecorded portion (corresponding to the measurement result 3823) and the length of the current recording mark (corresponding to the measurement result 3807). The value is stored corresponding to the combination of (correspondence), and the corresponding stored value is output. The first variable delay unit 3811 delays the recording signal 3806 according to the first memory output 3810 and outputs a signal 3812.

  In the second delay circuit 3813, the measurement results 3807 and 3825 are input to the second memory 3814, and the second memory 3814 outputs the second memory output 3815. Here, as shown in Table 17 (b), in the second memory 3814, the length of the current recording mark (corresponding to the measurement result 3807) and the length of the immediately non-recorded portion (corresponding to the measurement result 3825) are stored. And the corresponding stored value is stored, and the corresponding stored value is output. The second variable delay unit 3816 delays the recording signal 3806 and outputs a signal 3817 according to the second memory output 3815.

  The signal 3812 and the signal 3817 are input to an AND circuit 3818 and output as a signal 3819.

  The output signal 3819 is input to the laser driving circuit 3820, and the light source is driven to form an optical driving waveform 3821, and recording marks 3901 and 3902 are formed.

  As described above, in the seventeenth embodiment, when forming the recording marks 3901 and 3902, the recording power is adjusted according to the combination of the length of the immediately preceding non-recording portion and the length of the current recording mark to be recorded. The drive start time is delayed to compensate for the difference in thermal effect at the mark start end due to the difference in the length of the immediately preceding unrecorded portion and the difference in the thermal history at the mark start end due to the difference in the length of the current recorded mark. Therefore, the starting end of the recording mark can be formed at a correct position. In addition, according to the combination of the length of the recording mark to be recorded and the length of the non-recording portion immediately after, the drive end time at the recording power is ended earlier, and the mark end portion due to the difference in the length of the recording mark And the difference in heat history at the end of the mark due to the difference in the length of the non-recorded portion immediately after, so that the end of the recorded mark can be formed at the correct position.

Here, the optical drive waveform is driven between the recording power and the erasing power, but it may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 18)
An optical drive waveform 4041 in FIG. 41 is an optical drive waveform in the eighteenth embodiment of the present invention.

  The optical drive waveform 4041 is composed of a plurality of pulses. Further, with respect to the optical drive waveform 4041, the drive start time of the first pulse is delayed and the drive end time of the last pulse is earlier with respect to the signal 4100 obtained by delaying the recording signal 4006 by a fixed amount K. .

  In the case of the (1, 7) modulation as an example, the drive start delay amount of the first pulse is, as shown in Table 18 (a), the length of the immediately preceding non-recording portion and the length of the recording mark to be recorded. Is determined according to the combination of

  For example, the length of the non-recording portion immediately before the recording mark 4101 should be T4101 = 2Tw, and the length to be recorded is T4102 = 2Tw (Tw is the detection window width), so the recording start time is B18 (2 , 2), the length of the non-recording portion immediately before the recording mark 4102 should be T4103 = 4Tw, and the length to be recorded is T4104 = 8Tw, so that the recording start time is B18 (4,8). A) delay.

  In the case of (1, 7) modulation, the drive end delay amount of the last pulse is, as shown in Table 18 (b), as shown in Table 18 (b), the length of a recording mark to be recorded and the length of a non-recording portion immediately after it. Is determined according to

  For example, the length of the recording mark 4101 to be recorded is T4102 = 2 Tw (Tw is the detection window width), and the length of the non-recording portion immediately after is T4103 = 4 Tw, so that the end time is E18 (2, 4), the length of the recording mark 4102 to be recorded is T4104 = 8Tw, and the length of the non-recording portion immediately after is T4105 = 3Tw, so the end time is only E18 (8,3). Be faster.

  If the length of the mark to be recorded is the same, the shorter the length of the immediately preceding non-recording portion, the greater the thermal effect of the previous recording power on the beginning of the current recording mark, and the greater the extension of the mark beginning. Therefore, there is a tendency that B18 (2, N)> B18 (3, N) >> ...> B18 (8, N) (N is an integer of 2 to 8).

  If the length of the previous unrecorded portion is the same, the shorter the length of the mark to be recorded, the easier it is to obtain the quenching condition at the beginning of the mark, and in the case of a phase change medium that forms a mark by quenching after heating. Has a large extension at the mark start end. Therefore, there is a tendency that B18 (N, 2)> B18 (N, 3) >> B18 (N, 8).

  If the length of the unrecorded portion immediately after is the same, the longer the mark length to be recorded, the greater the effect of heat accumulation at the mark end portion, and the greater the extension of the end. Therefore, there is a tendency that E18 (8, N)> E18 (7, N) >>...> E18 (2, N) (N is an integer of 2 to 8).

  If the length of the mark to be recorded is the same, as the length of the non-recorded portion immediately after is shorter, the temperature of the mark end portion is less likely to decrease, and the end extension is larger. Therefore, there is a tendency that E18 (N, 2)> E18 (N, 3) >>...> E18 (N, 8) (N is an integer of 2 to 8).

  As a result, it is possible to correct the difference in the thermal effect at the mark start end due to the difference in the length of the immediately preceding non-recorded portion and the difference in the thermal history at the mark start end due to the difference in the record mark length, and the difference in the record mark length. The difference in heat history at the end of the mark due to the difference in the heat accumulation at the end of the mark and the difference in the length of the non-recorded portion immediately after can also be corrected, so that the start and end of the recording marks 4101 and 4102 are at the correct positions. It is formed.

  Note that here, the optical drive waveform 4041 is driven between the recording power and the erasing power, but if it is driven in accordance with the recording medium, such as between the recording power and the reproducing power, or between the recording power and 0. Good.

  FIG. 40 is a block diagram of a recording system of an optical disc device capable of obtaining an optical drive waveform according to Embodiment 18 of the present invention.

  40, reference numeral 4001 denotes a clock generation circuit, 4002 denotes a clock signal, 4003 denotes a recording signal generation circuit, 4004 denotes a recording signal output from the recording signal generation circuit 4003, 4005 denotes an H level period length measuring circuit, and 4006 denotes an H level period length. The recording signal after passing through the measuring circuit 4005, 4007 is an H level period measurement result output, 4008 is a pulse dividing circuit, 4009 is a leading pulse, 4010 is an intermediate pulse, 4011 is a last pulse, 4012 is a first delay circuit, and 4013 is a first delay circuit. 1 memory, 4014 is the first memory output, 4015 is the first variable delay, 4016 is its output, 4017 is the second delay circuit, 4018 is the second memory, 4019 is the second memory output, 4020 is the second variable delay , 4021 is its output, 4022 is a multi-pulse generation circuit, 4023 is an inversion circuit, 24 is an AND circuit, 4025 is an intermediate multipulse, 4026 is a fixed delay device, 4027 is its output, 4028 is a multipulse generation circuit, 4029 is an inversion circuit, 4030 is an AND circuit, 4031 is a last multipulse, 4032 is a selector, 4033 Is its output, 4034 is its OR circuit, 4035 is its output, 4036 is its AND circuit, 4037 is its output, 4038 is its selector, 4039 is its output, 4040 is the laser drive circuit, 4040 is the light drive waveform, 4042 is the gate generation circuit , 4043 are its output, 4044 is a switch, and 4045 is a select signal. Here, the selectors 4032 and 4038 select and output the X input when the select signal 4045 is at the L level, and select and output the Y input when the select signal 4045 is at the H level. Further, reference numeral 4046 denotes an L-level period length measuring circuit 1, 4047 denotes a measurement result output thereof, and 4048 denotes an L-level period length measuring circuit 2, 4049 denotes a measurement result output thereof.

  First, the operation when the switch 4044 is off, that is, when the select signal 4045 is at the L level, will be described with reference to the timing chart in FIG.

  The clock generation circuit 4001 outputs a channel clock 4002 whose cycle is the detection window width Tw. The duty is variable.

  The recording signal 4004 output from the recording signal generation circuit 4003 in synchronization with the rise of the channel clock signal 4002 from the clock generation circuit 4001 is supplied to the H level period length measurement circuit 4005 and the L level period length measurement circuit 1 (4046). The signal is input to the L-level period length measurement circuit 2 (4048).

  The L level period length measurement circuit 1 (4046) measures the length of the L level period of the recording signal 4004, and outputs a measurement result 4047. The measurement result 4047 is output in synchronization with the rising of the H level immediately after the measured L level of the recording signal 4006. That is, if the length of the L-level period is represented by the number of channel clocks, the length of the L-level period T4101 is 2, and the measurement result 3407 is 2 at the rise of the H-level period T4102 immediately after the L-level. The length of the L-level period T4103 is 4, and the measurement result 4047 becomes 4 at the rise of the immediately subsequent H-level period T4104.

  Then, the measurement result 4047 is input to the first delay circuit 4012.

  The H level period length measuring circuit 4005 measures the length of the H level period of the recording signal 4004, and outputs a recording signal 4006 and a measurement result 4007 again. The measurement result 4007 is output in synchronization with the rise of the measured H level of the recording signal 4006. That is, if the length of the H-level period is expressed by the number of channel clocks, the length of the H-level period T4102 is 2, and the measurement result 4007 becomes 2 at the rise of the H-level period T4102. The length of T4104 is 8, and the measurement result 4007 becomes 8 at the rise of the H-level period T4104.

  Then, the measurement result 4007 is input to the first delay circuit 4012 and the second delay circuit 4017.

  The L-level period length measurement circuit 2 (4048) measures the length of the L-level period of the recording signal 4004, and outputs a measurement result 4049. The measurement result 4049 is output in synchronization with the rise of the H level immediately before the measured L level of the recording signal 4006. That is, if the length of the L-level period is represented by the number of channel clocks, the length of the L-level period T4103 is 4, and the measurement result 4049 is 4 at the rise of the H-level period T4102 immediately before the L-level. The length of the L level period T4105 is 3, and the measurement result 4049 becomes 3 at the rising edge of the immediately preceding H level period T4104.

  Then, the measurement result 4049 is input to the second delay circuit 4017.

  In the first delay circuit 4012, the measurement results 4007 and 4047 are input to a first memory 4013, and a first memory output 4014 is output from the first memory 4013. Here, as shown in Table 18 (a), the first memory 4013 stores the length of the immediately preceding unrecorded portion (corresponding to the measurement result 4047) and the length of the current recording mark (corresponding to the measurement result 4007). And the corresponding stored value is stored, and the corresponding stored value is output.

  In the second delay circuit 4017, the measurement results 4007 and 4049 are input to a second memory 4018, and a second memory output 4019 is output from the second memory 4018. Here, as shown in Table 18 (b), the second memory 4018 stores the length of the current recording mark (corresponding to the measurement result 4007) and the length of the immediately non-recorded portion (corresponding to the measurement result 4049). And the corresponding stored value is stored, and the corresponding stored value is output.

  On the other hand, the recording signal 4006 is divided by a pulse dividing circuit 4008 into a leading pulse 4009, an intermediate pulse 4010, and a last pulse 4011. In this example, the leading pulse 4009 rises at the rise of the recording signal 4006 and falls after Tw, and the intermediate pulse 4010 rises Tw after the rise of the recording signal 4006 and falls Tw before the fall of the recording signal 4006. The last pulse 4011 is a signal that rises Tw before the fall of the recording signal 4006 and falls at the fall of the recording signal 4006. When the H level period of the recording signal 4006 is 2 Tw, no intermediate pulse is generated.

  The first pulse 4009 is delayed by the first variable delay unit 4015 by the first memory output 4014 to become a signal 4016.

  The intermediate pulse 4010 is input to a multi-pulse generation circuit 4022, becomes an intermediate multi-pulse 4025, is delayed by a fixed delay unit 4026 having a delay amount K, and becomes a signal 4027.

  The last pulse 4011 becomes the last multipulse 4031 in the multipulse generation circuit 4028, is selected by the selector 4032, becomes a signal 4033, is delayed by the second variable delay unit 4020 according to the second memory output 4019, and becomes the signal 4021.

  The output 4035 of the OR circuit 4034 of the signal 4016, the signal 4027, and the signal 4021 is selected by the selector 4038, and is input to the laser driving circuit 4040, and the light source is driven to form the optical driving waveform 4041, and the recording marks 4101 and 4102 are formed. .

  Next, the case where the switch 4044 is ON will be described with reference to FIG.

  Gate generation circuit 4042 outputs an H level only when measurement result 4007 is 2. Therefore, the select signal 4045 becomes H level when the measurement result 4007 is 2, and the selectors 4032 and 4038 select and output the Y input. Therefore, the last pulse 4011 is input to the second variable delay device 4020 and is delayed to become the signal 4021. Further, the output 4037 of the signal 4021 and the signal 4016 by the AND circuit 4036 is guided to the laser driving circuit 4040. Therefore, when the mark to be recorded is 2 Tw, a pulse width equal to or smaller than Tw can be created, and smaller marks can be handled.

  When the measurement result 4007 is other than 2, it is the same as when the switch 4044 is OFF.

  As described above, in the eighteenth embodiment, when the recording mark 4101 or 4102 is formed, the recording mark 4101 or 4102 is driven by a plurality of pulses, and according to the combination of the length of the immediately preceding non-recording portion and the length of the recording mark to be recorded. By delaying the driving start time of the first pulse, the difference in the thermal effect of the previous recording power due to the difference in the length of the immediately preceding non-recording portion and the difference in the thermal history of the mark start portion due to the difference in the length of the recording mark , The start of the mark can be formed at the correct position, and the drive of the last pulse is terminated early according to the length of the recording mark to be recorded, and the end of the mark due to the difference in the length of the recording mark The difference in heat history at the end of the mark due to the difference in the heat accumulation at the end of the mark due to the difference in the length of the non-recorded portion immediately after is corrected so that the end of the recorded mark can also be formed at the correct position. . Further, by driving in a plurality of pulses, the heat load applied to the medium can be reduced, and there is also an effect of reducing deterioration due to repeated recording.

  By changing the method of dividing the leading pulse, the intermediate pulse, and the last pulse by the pulse dividing circuit, various pulse patterns can be handled.

Here, the optical drive waveform is driven between the recording power and the erasing power, but it may be driven between the recording power and the reproducing power, between the recording power and 0, etc. in accordance with the recording medium.
(Example 19)
FIG. 43 shows a recording waveform of the optical information recording method according to the nineteenth embodiment of the present invention. (43a) is the modulation data at the maximum inversion interval (hereinafter referred to as Tmax), (43b) is the recording waveform for forming a recording mark corresponding to the modulation data (43a), and (43c) is formed. This is a recording mark.

  (43d) is the modulation data of the minimum inversion interval (hereinafter referred to as Tmin), (43e) is a recording waveform for forming a recording mark corresponding to the modulation data (43d), and (43f) is formed. This is a recording mark.

  The recording waveform (43b) is composed of a first pulse followed by (Tmax-Tmin) / Tw (Tw is a detection window width; hereinafter, referred to as Tw) pulses, and is composed of modulated data (43a). The interval between the rising edge (E1) and the rising edge of the first pulse (E2) is x (0 <x), and the rising edge (E1) of the modulation data (43a) and the falling edge of the first pulse (E1). E3) is Tmin + y (y <0.5 Tw), and the interval between the rising edge (E1) of the modulated data (43a) and the rising edge (E4) of the first subsequent pulse is Tmin + 0.5 Tw-z (0). ≦ z <0.5 Tw), the interval between the rising edge (E1) of the modulation data (43a) and the falling edge (E5) of the first subsequent pulse is Tmin + Tw, and the modulation data (43a) The interval between the rising edge (E1) and the rising edge of the n-th subsequent pulse (n is an integer, 1 ≦ n ≦ (T−Tmin) / Tw) is Tmin + nTw−0.5Tw−z (0 ≦ z <0.5Tw). ), And the interval between the rising edge (E1) of the modulation data (43a) and the falling edge of the n-th (n is an integer, 1 ≦ n ≦ (T−Tmin) / Tw) subsequent pulse is Tmin + nTw.

  Therefore, the interval T1 between the falling edge (E3) of the first pulse and the rising edge (E4) of the first subsequent pulse is 0.5 Tw-zy, and the interval T2 between the subsequent pulses is 0.5 Tw. Since −z, when y ≠ 0, a state of T1 ≠ T2 can be obtained.

  Here, since the extension d1 of the recording mark (43c) can be corrected by setting x, a recording mark having a length corresponding to Tmax can be correctly recorded.

  In addition, when setting x, it is sufficient to set it in the state of y = 0.

  The recording waveform (43e) is composed of only the first pulse, and the interval between the rising edge (E6) of the modulated data (43d) and the rising edge (E7) of the first pulse is a mark of the maximum inversion interval. X (0 <x) set so as to correctly record the data, and the interval between the rising edge (E6) of the modulation data (43d) and the falling edge (E8) of the first pulse is Tmin + y (y <0.5 Tw). ).

  Here, y can be set so that the recording mark (43f) has a length corresponding to Tmin.

  As described above, x can be set so that the length of the recording mark formed by the recording waveform (43b) corresponds to the maximum inversion interval Tmax, and is formed by the recording waveform (43e). Since y can be set so that the length of the recording mark corresponds to the minimum inversion interval Tmin, a desired mark length can be obtained. .

  In the recording waveforms (43b) and (43e), the power is modulated between the peak power and the bias power. When recording on a write-once medium or a magneto-optical medium, the peak power is used as the recording power and the bias power is used. The recording power may be set to the reproducing power, and when recording on the phase change medium, the peak power may be set to the recording power and the bias power may be set to the erasing power.

  FIG. 44 shows a recording waveform when the method for recording optical information in the nineteenth embodiment is applied to (1, 7) modulation.

  Here, Tmax = 8 Tw, Tmin = 2 Tw, x = Tw, y = 0.25 Tw, and z = 0.

  (44a) is modulation data at the maximum inversion interval 8 Tw, and (44b) is a recording waveform for forming a recording mark corresponding to the modulation data (44a).

  (44c) is 7 Tw modulation data, and (44d) is a recording waveform for forming a recording mark corresponding to the modulation data (44c).

  (44e) is 6 Tw modulation data, and (44f) is a recording waveform for forming a recording mark corresponding to the modulation data (44e).

  (44g) is 5 Tw modulation data, and (44h) is a recording waveform for forming a recording mark corresponding to the modulation data (44g).

  (44i) is 4 Tw modulation data, and (44j) is a recording waveform for forming a recording mark corresponding to the modulation data (44i).

  (44k) is 3 Tw modulation data, and (441) is a recording waveform for forming a recording mark corresponding to the modulation data (44k).

  (44m) is modulation data with a minimum inversion interval of 2 Tw, and (44n) is a recording waveform for forming a recording mark corresponding to the modulation data (44m).

  The recording waveform (44b) is composed of a first pulse followed by (8Tw-2Tw) / Tw = 6 subsequent pulses, and the rising of the modulation data (44a) and the rising of the first pulse. Is x = Tw, the interval between the rising edge of the modulation data (44a) and the falling edge of the first pulse is Tmin + y = 2.25Tw, and the rising edge of the modulation data (44a) and the nth Is Tmin + nTw-0.5Tw-z = (1.5 + n) Tw, and the interval between the rise of the modulation data (44a) and the fall of the nth subsequent pulse is Tmin + nTw = ( 2 + n) Tw.

  The recording waveform (44d) is composed of a first pulse followed by (7Tw−2Tw) / Tw = 5 subsequent pulses, and the rising of the modulation data (44c) and the rising of the first pulse. Is x = Tw, the interval between the rising edge of the modulation data (44c) and the falling edge of the first pulse is Tmin + y = 2.25Tw, and the rising edge of the modulation data (44c) and the nth Is Tmin + nTw-0.5Tw-z = (1.5 + n) Tw, and the interval between the rising edge of the modulation data (44c) and the falling edge of the nth subsequent pulse is Tmin + nTw = ( 2 + n) Tw.

  The recording waveform (44f) is composed of a first pulse followed by (6Tw−2Tw) / Tw = 4 subsequent pulses, and the rising of the modulation data (44e) and the rising of the first pulse. Is x = Tw, the interval between the rise of the modulation data (44e) and the fall of the first pulse is Tmin + y = 2.25Tw, and the rise of the modulation data (44e) and the nth Is Tmin + nTw-0.5Tw-z = (1.5 + n) Tw, and the interval between the rise of the modulation data (44e) and the fall of the nth subsequent pulse is Tmin + nTw = ( 2 + n) Tw.

  The recording waveform (44h) is composed of a first pulse followed by (5Tw−2Tw) / Tw = 3 subsequent pulses, and the rising of the modulation data (44g) and the rising of the first pulse. Is x = Tw, the interval between the rising edge of the modulation data (44g) and the falling edge of the first pulse is Tmin + y = 2.25Tw, and the rising edge of the modulation data (44g) and the nth Is Tmin + nTw-0.5Tw-z = (1.5 + n) Tw, and the interval between the rise of the modulation data (44g) and the fall of the nth subsequent pulse is Tmin + nTw = ( 2 + n) Tw.

  The recording waveform (44j) is composed of a first pulse followed by (4Tw−2Tw) / Tw = 2 subsequent pulses, and the rising of the modulation data (44i) and the rising of the first pulse. Is x = Tw, the interval between the rising edge of the modulation data (44i) and the falling edge of the first pulse is Tmin + y = 2.25Tw, and the rising edge of the modulation data (44i) and the nth The interval between the rising edge of the following pulse is Tmin + nTw-0.5 Tw-z = (1.5 + n) Tw, and the interval between the rising edge of the modulation data (44i) and the falling edge of the nth subsequent pulse is Tmin + nTw = ( 2 + n) Tw.

  The recording waveform (441) is composed of a first pulse followed by (3Tw−2Tw) / Tw = 1 subsequent pulses, and the rising of the modulation data (44k) and the rising of the first pulse. Is x = Tw, the interval between the rising edge of the modulation data (44k) and the falling edge of the first pulse is Tmin + y = 2.25Tw, and the rising edge of the modulation data (44k) and the nth Is Tmin + nTw-0.5Tw-z = (1.5 + n) Tw, and the interval between the rising edge of the modulation data (44k) and the falling edge of the nth subsequent pulse is Tmin + nTw = ( 2 + n) Tw.

  The recording waveform (44n) is composed of only the first pulse, and the interval between the rise of the modulation data (44m) and the rise of the first pulse is x = Tw, and the modulation data (44m) The interval between the rise of the first pulse and the fall of the first pulse is Tmin + y = 2.25 Tw.

  In the above recording, the interval between the falling edge of the first pulse and the rising edge of the first subsequent pulse is 0.25 Tw, the interval between subsequent pulses is 0.5 Tw, and different.

  FIG. 45 shows a measurement result of the length of a recording mark formed with respect to a modulation data inversion interval when actually recorded on a rewritable phase-change optical disc by the recording method of FIG. Indicated.

  The recording film of the disk used was a GeTeSb-based material, and the film thickness was 250 Å. Further, a ZnS-SiO2 mixed layer is provided above and below the recording film. The substrate used was a 5-inch polycarbonate substrate on which tracks had been formed in advance. The disk was rotated, and recording was performed at a linear velocity of 6 m / s using a head with a laser wavelength of 830 nm and an objective lens of NA 0.5 with a minimum mark length of 0.8 μm (2 Tw, Tw = 67 ns). The recording power is 15.6 mW and the erasing power is 8 mW.

  In FIG. 45, white circles are the result of the conventional recording method, and a recording mark longer than the inversion interval in the modulation data is formed. On the other hand, solid circles are the results using the recording waveform of FIG. 44 which is an embodiment of the present invention, and a recording mark having a length substantially equal to the inversion interval in the modulation data was formed. That is, a recording mark of a desired length was obtained.

  As described above, according to this embodiment, the recording waveform for forming the recording mark corresponding to the reversal interval T is (T−Tmin) / Tw (Tmin is the minimum reversal interval) , Tw are a plurality of pulse trains composed of subsequent pulses of the detection window width). The interval between the rising edge of the modulation data and the rising edge of the first pulse is x (0 <x). The interval from the falling edge of the first pulse is Tmin + y (Tmin is the minimum inversion interval, y <0.5 Tw, Tw is the detection window width), and the rising edge of the modulation data and the nth (n is an integer, 1) ≦ n ≦ (T−Tmin) / Tw, where Tmin is the minimum inversion interval, and Tw is the detection window width, and the interval from the rising edge of the subsequent pulse is Tmin + nTw−0.5Tw−z (0 ≦ z <0.5Tw, Tmi). Is the minimum inversion interval, Tw is the detection window width, and the rising edge of the modulation data and the nth (n is an integer, 1 ≦ n ≦ (T−Tmin) / Tw, Tmin is the minimum inversion interval, and Tw is the detection window width ) Is Tmin + nTw (Tmin is the minimum inversion interval, Tw is the detection window width), and x is set so that the mark of the maximum inversion interval is formed to a desired length. By setting y so that the mark at the inversion interval is formed to have a desired length, a mark having a desired length can be obtained.

  FIG. 46 is a block diagram showing an optical information recording apparatus capable of obtaining a recording waveform according to the nineteenth embodiment of the present invention. In FIG. 46, reference numeral 4600 denotes a clock generator for generating a clock whose cycle is equal to the detection window width; 4601, a modulator for modulating input data; 4602, a pulse generator for outputting a pulse of the minimum inversion interval from the output of the modulator 4601; A circuit 4603 for outputting a pulse obtained by delaying the rising edge of the output pulse of the pulse generation circuit 4602; and 4604 for outputting a pulse obtained by delaying the falling edge of the output pulse of the first delay circuit 4603. A second delay circuit 4605 is a multi-pulse generation circuit that outputs a plurality of pulse trains using the clock, the output of the modulator 4601, and the output of the pulse generation circuit 4602, and 4606 is an output of the second delay circuit 4604. A logical sum circuit for outputting a logical sum with the output of the multi-pulse generating circuit 4605, The laser drive circuit 607 for driving the laser of the optical head using an output of the OR circuit 4606, 4608 is an optical head, 4609 is an optical disc.

  The operation of the optical information recording apparatus configured as described above will be described with reference to FIG.

  The clock generator 4600 outputs a clock (47b) whose period is the detection window width Tw. The duty is variable.

  The modulator 4601 receives the clock (47b) and outputs modulated data (47a) synchronized with the clock.

  The pulse generation circuit 4602 receives the modulation data (47a) and outputs a pulse (47c) having a pulse width of the minimum inversion interval Tmin from the rise of the modulation data (47a).

  The first delay circuit 4603 receives the pulse (47c) and outputs a first delay pulse (47d) obtained by delaying the rising edge of the pulse (47c) by x.

  The second delay circuit 4604 receives the first delay pulse (47d) and outputs a second delay pulse (47e) obtained by delaying the falling edge of the first delay pulse (47d) by y.

  The multi-pulse generation circuit 4605 receives the modulation data (47a), the pulse (47c), and the clock (47b), and receives a signal from the falling edge of the pulse (47c) to the falling edge of the modulation data (47a). During this period, a multi-pulse (47f) that outputs a signal having a phase opposite to that of the clock (47b) is output.

  The OR circuit 4606 receives the second delay pulse (47e) and the multi-pulse (47f), and outputs a drive signal (47g).

  The laser drive circuit 4608 drives the laser of the optical head 8 according to the drive signal (47g) like an optical drive waveform (47h), and forms a recording mark on the optical disc 4609.

  In the optical drive waveform (47h), the power is modulated between the peak power and the bias power. When recording on a write-once medium or a magneto-optical medium, the peak power is set to the recording power and the bias power is set to the reproduction power. When recording on a phase change medium, the peak power may be set to the recording power and the bias power may be set to the erasing power.

  With this configuration, the length of the recording mark corresponding to the maximum inversion interval can be set to a desired value by the delay amount x of the first delay pulse (47d), and the delay amount y of the second delay pulse (47e) can be set. The length of the recording mark corresponding to the minimum inversion interval can be set to a desired value.

FIG. 2 is a block diagram of a recording system of the optical disc device according to the first embodiment of the present invention. 2 is a timing chart for explaining the operation of the apparatus in FIG. 1. FIG. 7 is a block diagram of a recording system of an optical disc device according to a second embodiment of the present invention. 4 is a timing chart for explaining the operation of the apparatus in FIG. 3. FIG. 9 is a block diagram of a recording system of an optical disc device according to a third embodiment of the present invention. 6 is a timing chart for explaining the operation of the apparatus in FIG. 5. FIG. 14 is a block diagram of a recording system of an optical disc device according to a fourth embodiment of the present invention. 8 is a timing chart for explaining the operation of the apparatus in FIG. 7. FIG. 14 is a block diagram of a recording system of an optical disc device according to a fifth embodiment of the present invention. 10 is a timing chart for explaining the operation of the apparatus in FIG. 9. FIG. 14 is a block diagram of a recording system of an optical disc device according to a sixth embodiment of the present invention. 12 is a timing chart for explaining the operation of the apparatus in FIG. 11. FIG. 18 is a block diagram of a recording system of an optical disc device according to a seventh embodiment of the present invention. 14 is a timing chart for explaining the operation of the apparatus in FIG. 13. FIG. 18 is a block diagram of a recording system of an optical disc device according to an eighth embodiment of the present invention. 16 is a timing chart for explaining the operation of the apparatus in FIG. 15. 16 is a timing chart for explaining the operation of the apparatus in FIG. 15. FIG. 21 is a block diagram of a recording system of an optical disc device according to Embodiment 9 of the present invention. 19 is a timing chart for explaining the operation of the apparatus in FIG. 18. FIG. 21 is a block diagram of a recording system of an optical disc device according to Embodiment 10 of the present invention. 21 is a timing chart for explaining the operation of the apparatus in FIG. 20. 21 is a timing chart for explaining the operation of the apparatus in FIG. 20. FIG. 21 is a block diagram of a recording system of an optical disc device according to Embodiment 11 of the present invention. 24 is a timing chart for explaining the operation of the apparatus of FIG. 23. FIG. 21 is a block diagram of a recording system of an optical disc device according to Embodiment 12 of the present invention. 26 is a timing chart for explaining the operation of the apparatus in FIG. 25. 26 is a timing chart for explaining the operation of the apparatus in FIG. 25. FIG. 21 is a block diagram of a recording system of an optical disc device according to Embodiment 13 of the present invention. 29 is a timing chart for explaining the operation of the apparatus in FIG. 28. FIG. 21 is a block diagram of a recording system of an optical disc device according to Embodiment 14 of the present invention. 31 is a timing chart for explaining the operation of the apparatus in FIG. 30. 31 is a timing chart for explaining the operation of the apparatus in FIG. 30. FIG. 21 is a block diagram of a recording system of an optical disc device according to Embodiment 15 of the present invention. 34 is a timing chart for explaining the operation of the apparatus in FIG. 33. FIG. 26 is a block diagram of a recording system of an optical disc device according to Embodiment 16 of the present invention. 36 is a timing chart for explaining the operation of the apparatus in FIG. 35. 36 is a timing chart for explaining the operation of the apparatus in FIG. 35. FIG. 21 is a block diagram of a recording system of an optical disc device according to Embodiment 17 of the present invention. 39 is a timing chart for explaining the operation of the apparatus in FIG. 38. FIG. 21 is a block diagram of a recording system of an optical disc device according to Embodiment 18 of the present invention. 41 is a timing chart for explaining the operation of the apparatus in FIG. 40. 41 is a timing chart for explaining the operation of the apparatus in FIG. 40. FIG. 21 is a recording waveform chart according to the nineteenth embodiment of the present invention. FIG. 21 is a recording waveform diagram in (1, 7) modulation in Example 19 of the present invention. FIG. 21 is a diagram illustrating the length of a recording mark for modulated data in Embodiment 19 of the present invention. FIG. 21 is a block diagram of an optical disc device according to Embodiment 19 of the present invention. 47 is a timing chart for explaining the operation of the apparatus in FIG. 46. FIG. 7 is a recording waveform diagram in a conventional recording method.

Explanation of reference numerals

4001 clock generation circuit 4003 recording signal generation circuit 4005 H level period length measurement circuit 4008 pulse division circuit 4012 first delay circuit 4017 second delay circuit 4022 multi-pulse generation circuit 4028 multi-pulse generation circuit 4034 OR circuit 4036 AND circuit 4040 laser drive circuit 4041 Optical drive waveform

Claims (2)

A method for recording optical information by forming a large number of recording marks on a recording medium by light irradiation from a light source such as a laser,
In forming one recording mark of the present time, the start time of driving with the recording power of the light source for forming the current recording mark is changed according to the length of the current recording mark, and A method for changing the end time of the drive with the recording power of the light source for forming the current recording mark according to the length of the recording mark. Recording signal generating means for generating a recording signal;
First measuring means for measuring an output period of a recording signal for forming a current recording mark;
First delay means for delaying a recording signal for recording a current recording mark in accordance with a measurement result of the first measuring means;
A second delay unit that delays a recording signal for recording a current recording mark according to a measurement result of the first measurement unit;
Driving means for driving the light source with the recording power from the rising of the recording signal after the delay by the first delay means to the falling of the recording signal after the delay by the second delay means;
A recording device for optical information, comprising:

Images