Method and device for recording optical information

Claim 2

In an optical information recording method which switches and irradiates laser light having a plurality of powers onto an optical storage medium having a thin storage film which changes reversibly between optically recognizable states, and which overwrites a digital signal having modulated pulse widths by employing a light beam, the optical information recording method wherein, in the case where a record mark is formed by irradiating laser light by a recording waveform which has a recording pulse train, comprising a plurality of pulses where said laser light is modulated between a first power previously set to a power greater than a recording power for recording said thin storage film and a second power previously set to a power lower than said first power, and which also has, after said recording pulse train, a cooling pulse which irradiates laser light by a cooling power lower than a bias power where the laser light power is less than said recording power, laser light irradiation at said bias power is performed between said recording pulse train and said cooling pulse.

Claim 3

In an optical information recording method which switches and irradiates laser light having a plurality of powers onto an optical storage medium having a thin storage film which changes reversibly between optically recognizable states, and which overwrites a digital signal having modulated pulse widths by employing a light beam, the optical information recording method wherein, in the case where a record mark is formed by irradiating laser light by a recording waveform which has a recording pulse train, comprising a plurality of pulses where said laser light is modulated between a first power previously set to a power greater than a recording power for recording said thin storage film and a second power previously set to a power lower than said first power, and which also has, after said recording pulse train, a cooling pulse which irradiates laser light by a cooling power lower than a bias power where the laser light power is less than said recording power, either laser light irradiation start time at said cooling power with respect to an end point of said recording pulse train or laser light irradiation time at said cooling power is varied according to the length of said record mark.

Claim 4

The optical information recording method as set forth in claim 3, wherein said laser light irradiation time at said cooling power is made longer when a short record mark is recorded than when a long record mark is recorded.

Claim 5

The optical information recording method as set forth in claim 3, wherein said laser light irradiation start time at said cooling power is quickened when a short record mark is recorded than when a long record mark is recorded.

Claim 6

In an optical information recording method which switches and irradiates laser light having a plurality of powers onto an optical storage medium having a thin storage film which changes reversibly between optically recognizable states, and which overwrites a digital signal having modulated pulse widths by employing a light beam, the optical information recording method wherein, in the case where a record mark is formed by irradiating laser light by a recording waveform which has a recording pulse train, comprising a plurality of pulses where said laser light is modulated between a first power previously set to a power greater than a recording power for recording said thin storage film and a second power previously set to a power lower than said first power, and which also has, after said recording pulse train, a cooling pulse which irradiates laser light by a cooling power lower than a bias power where the laser light power is less than said recording power, either laser light irradiation start time at said cooling power with respect to an end point of said recording pulse train or laser light irradiation time at said cooling power is varied only when the length of said record mark is less than a predetermined length.

Claim 7

In an optical information recording method which switches and irradiates laser light having a plurality of powers onto an optical storage medium having a thin storage film which changes reversibly between optically recognizable states, and which overwrites a digital signal having modulated pulse widths by employing a light beam, the optical information recording method wherein, in the case where a record mark is formed by irradiating laser light by a recording waveform which has a recording pulse train, comprising a plurality of pulses where said laser light is modulated between a first power previously set to a power greater than a recording power for recording said thin storage film and a second power previously set to a power lower than said first power, and which also has, after said recording pulse train, a cooling pulse which irradiates laser light by a cooling power lower than a bias power where the laser light power is less than said recording power, a laser light irradiation period at said bias power is provided between said recording pulse train and the laser light irradiation which is performed at said cooling pulse; laser light irradiation start time at said cooling power with respect to an end point of said recording pulse train and laser light irradiation time at said cooling power are set to predetermined times, respectively; and only when the length of said record mark is less than a predetermined length, laser light irradiation is performed at said cooling power.

Claim 8

The optical information recording method as set forth in claim 7, wherein, only when the length of said record mark is shortest, laser light irradiation at said cooling power is performed.

Claim 9

In an optical information recording method which switches and irradiates laser light having a plurality of powers onto an optical storage medium having a thin storage film which changes reversibly between optically recognizable states, and which overwrites a digital signal having modulated pulse widths by employing a light beam, the optical information recording method wherein, in the case where a record mark is formed by irradiating laser light by a recording waveform which has a recording pulse train, comprising a plurality of pulses where said laser light is modulated between a first power previously set to a power greater than a recording power for recording said thin storage film and a second power previously set to a power lower than said first power, and which also has, after said recording pulse train, a cooling pulse which irradiates laser light by a cooling power lower than a bias power where the laser light power is less than said recording power, said optical storage medium is rotated and driven at a constant angular velocity; and in a region of said optical storage medium inside at least a predetermined radius, when the length of said record mark is shorter than a predetermined length, it is selected either whether laser light irradiation start time at said cooling power level with respect to an end point of said recording pulse train is quickened or whether laser light irradiation time at said cooling power level is lengthened.

Claim 10

In an optical information recording method which switches and irradiates laser light having a plurality of powers onto an optical storage medium having a thin storage film which changes reversibly between optically recognizable states, and which overwrites a digital signal having modulated pulse widths by employing a light beam, the optical information recording method wherein, in the case where a record mark is formed by irradiating laser light by a recording waveform which has a recording pulse train, comprising a plurality of pulses where said laser light is modulated between a first power previously set to a power greater than a recording power for recording said thin storage film and a second power previously set to a power lower than said first power, and which also has, after said recording pulse train, a cooling pulse which irradiates laser light by a cooling power lower than a bias power where the laser light power is less than said recording power, said optical storage medium is rotated and driven at a constant angular velocity; only when the length of said record mark is less than a predetermined length, laser light irradiation start time at said cooling power with respect to an end point of the laser light irradiation at said recording power and laser light irradiation time at said cooling power are set to predetermined times, respectively; and in a region of said optical storage medium inside at least a predetermined radius, only when the length of said record mark is shorter than a predetermined length, laser light irradiation is performed at said cooling power.

Claim 11

The optical information recording method as set forth in claim 10, wherein, only when the length of said record mark is shortest, laser light irradiation at said cooling power is performed.

Claim 12

In an optical information recording method which switches and irradiates laser light having a plurality of powers onto an optical storage medium having a thin storage film which changes reversibly between optically recognizable states, and which overwrites a digital signal having modulated pulse widths by employing a light beam, the optical information recording method wherein: a record mark is formed by irradiating laser light by a recording waveform which has a recording pulse train comprising a plurality of pulses where said laser light is modulated between a first power previously set to a power greater than a recording power for recording said thin storage film and a second power previously set to a power lower than said first power; immediately after said recording pulse train, there is added a cooling pulse comprising a pulse train constituted by laser light which has at least two different powers where the laser light power is less than said first power; and at least one of the pulse train of said cooling pulse is a power smaller than a bias power.

Claim 13

In an optical information recording method which switches and irradiates laser light having a plurality of powers onto an optical storage medium having a thin storage film which changes reversibly between optically recognizable states, and which overwrites a digital signal having modulated pulse widths by employing a light beam, the optical information recording method wherein: a record mark is formed by irradiating laser light by a recording waveform which has a recording pulse train comprising a plurality of pulses where said laser light is modulated between a first power previously set to a power greater than a recording power for recording said thin storage film and a second power previously set to a power lower than said first power; and there is added a cooling pulse having a structure which has a period where the laser light is varied immediately after said recording pulse train and where the laser light is continuously varied to a power less than either said second power or a bias power.

Claim 14

The optical information recording method as set forth in claim 12, wherein said cooling pulse is constituted by previously set third and fourth powers of the laser light; said third power is a power greater than said fourth power and smaller than either said second power or said bias power; immediately after said recording pulse train, laser light irradiation at said third power is performed; and immediately after said laser light irradiation at said third power, laser light irradiation at said fourth power is performed.

Claim 15

The optical information recording method as set forth in claim 12, wherein said cooling pulse is constituted by previously set fifth and sixth powers of the laser light; said fifth power is a power greater than said bias power and said sixth power is a power smaller than said bias power; immediately after said recording pulse train, laser light irradiation at said fifth power is performed; and immediately after said laser light irradiation at said fifth power, laser light irradiation at said sixth power is performed.

Claim 16

The optical information recording method as set forth in claim 12, wherein said cooling pulse is constituted by previously set seventh, eighth, and ninth powers of the laser light; said seventh power and said ninth power are both smaller than said eighth power and are powers smaller than either said second power or said bias power; immediately after said recording pulse train, laser light irradiation at said seventh power is performed; immediately after said laser light irradiation at said seventh power, laser light irradiation at said eighth power is performed; and immediately after said laser light irradiation at said eighth power, laser light irradiation at said ninth power is performed.

Claim 17

The optical information recording method as set forth in claim 13, wherein said cooling power has both a period where the laser light is varied immediately after said recording pulse train and continuously to a power smaller than either said second power or said bias power and a period where from said power smaller than either said second power or said bias power, the laser light power is varied continuously to either said second power or said bias power.

Claim 18

The optical information recording method as set forth in any of claims 12 through 17, wherein between said recording pulse train and said cooling pulse, laser light irradiation is performed by either said second power or said bias power.

Claim 19

The optical information recording method as set forth in any of claims 12 through 17, wherein either cooling-power start time or the pulse configuration of said cooling pulse is varied according to the length of the record mark.

Claim 20

The optical information recording method as set forth in any of claims 12 through 17, wherein, when said optical storage medium is rotated at a constant angular velocity, either cooling-power start time or the pulse configuration of said cooling pulse is varied according to a radial position of said optical storage medium.

Claim 21

The optical information recording method as set forth in any of claims 1 through 20, wherein said record mark is formed by irradiating laser light by the recording pulse train constituted by a plurality of pulses modulated between the previously set first and second powers; and said recording pulse train irradiates said first power, which is constant, at the start edge of said recording pulse train and alternately switches and irradiates the laser light having said first and second powers at a portion other than the start edge of said recording pulse train with a cycle less than one cycle of a data clock.

Claim 22

The optical information recording method as set forth in any of claims 1 through 20, wherein said record mark is formed by irradiating laser light by the recording pulse train constituted by a plurality of pulses where the laser light is modulated between the previously set first and second powers; and said recording pulse train alternately switches and irradiates the laser light having said first and second powers with a cycle less than one cycle of a data clock.

Claim 23

An optical information recording method wherein: a record mark is formed by irradiating laser light by a recording pulse train constituted by a plurality of pulses where laser light is modulated between previously set first and second powers; said recording pulse train irradiates said first power, which is constant, at the start edge and the end edge of said recording pulse train when said first power of said laser light is greater than said second power, and between the start edge and the end edge of said recording pulse train, said recording pulse train alternately switches and irradiates said first power and said second power with a cycle less than one cycle of a data clock; and immediately after said recording pulse, laser light irradiation is performed with a cooling power which is a power lower than a bias power where the laser light power is less than said recording power.

Claim 24

The optical information recording method as set forth in claims 23, wherein said recording pulse train is a recording pulse train which changes positions of the start edge and the end edge of said recording pulse train in accordance with the length of the record mark and the spacing between the record marks.

Claim 25

The optical information recording method as set forth in any of claims 1 through 20, wherein said record mark is formed by irradiating laser light by the recording pulse train constituted by a plurality of pulses modulated between the previously set first and second powers; and said recording pulse train irradiates said first power, which is constant, at the start edge and the end edge of said recording pulse train, and between the start edge and the end edge of said recording pulse train, said recording pulse train alternately switches and irradiates said first power and said second power with a cycle less than one cycle of a data clock.

Claim 26

The optical information recording method as set forth in any of claims 1 through 20, wherein said record mark is formed by irradiating laser light by the recording pulse train constituted by a plurality of pulses modulated between the previously set first and second powers; said recording pulse train irradiates said first power, which is constant, at the start edge and the end edge of said recording pulse train, and between the start edge and the end edge of said recording pulse train, said recording pulse train alternately switches and irradiates said first power and said second power with a cycle less than one cycle of a data clock; and said recording pulse train changes positions of the start edge and the end edge of said recording pulse train in accordance with the length of the record mark and the spacing between the record marks.

Claim 27

The optical information recording method as set forth in claim 26, wherein between said recording pulse train and the laser light irradiation which is performed at said cooling power, laser light irradiation at said bias power is performed; and the time between the start of the laser light irradiation at the end edge pulse of said recording pulse train and the start of the laser light irradiation at said cooling power is constant.

Claim 28

The optical information recording method as set forth in claim 26, wherein the timing of the start of the laser light irradiation at said cooling power is based on the clock.

Claim 29

An optical information storage unit which is a disk storage unit which records a high period of data onto a disk in correspondence with a mark and records a low period of the data in correspondence with a space between marks, the optical information storage unit comprising: a start edge pulse generation circuit which generates a start edge pulse having a constant width at a start edge position of the high period of the data; a burst gate generation circuit which generates a burst gate signal at a middle position of the mark when the high period of the data is long and which generates no burst gate signal when the high period of the data is short; an end edge pulse generation circuit which generates an end edge pulse having a constant width at an end edge position of the high period of the data; a mark/space length detection circuit which generates an nT mark signal including said start edge pulse and said end edge pulse when the high period of the data has n clocks and which generates an mT mark signal including said end edge pulse and said start edge pulse of both edges of the space when the low period of the data has m clocks (where n and m are natural numbers existing in a data string); an encoder which generates a select signal, which is for controlling a start edge selector to be described later and an end edge selector to be described later, from said nT mark signal and said mT mark signal; a cooling-pulse generation circuit which generates a cooling pulse having a constant width from a delayed end edge pulse which is from a programmable end edge delay line to be described later; the start edge selector which selects and outputs one from a plurality of start edge values by said selector signal; a start edge sample/hold circuit which updates a start edge set value output of said start edge selector only when said start edge pulse appears and which holds a previous value when no start edge pulse appears; a programmable start edge delay line which varies a quantity of delay by the start edge set value of the output of said start edge sample/hold circuit and which outputs a delayed start edge pulse where said start edge pulse is delayed; the end edge selector which selects and outputs one from a plurality of end edge values by said selector signal; an end edge sample/hold circuit which updates an end edge set value output of said end edge selector only when said end edge pulse appears and which holds a previous value when no end edge pulse appears; the programmable end edge delay line which varies a quantity of delay by the end edge set value of the output of said end edge sample/hold circuit and then delays said end edge pulse and which outputs a delayed end edge pulse where said end edge pulse is delayed; a cooling-pulse delay line which varies a quantity of delay of said cooling pulse and outputs a delayed cooling pulse; an AND gate which performs a logical product between said burst pulse and the clock and outputs a burst pulse; an OR gate which performs a logical sum between said delayed start edge pulse, said burst pulse, and said delayed end edge pulse and outputs a recording signal; an inverter which inverts the cooling pulse signal which is from said cooling-pulse delay line; a bias current source which supplies a bias current of a laser diode to be described later; a recording-current source which supplies a recoding current of the laser diode in parallel with said bias current source; a light-reproducing current source which supplies a light reproducing current of the laser diode in parallel with said bias current source; a switch which turns the current of said recording-current source on and off by said recording current; a switch which turns the current of said bias current source on and off by said cooling pulse signal; and the laser diode which records disk signals driven in parallel by said bias current source, said recording-current source, and said light-reproducing current source.

Claim 30

An optical information storage unit which is a disk storage unit which records a high period of data onto a disk in correspondence with a mark and records a low period of the data in correspondence with a space between marks, the optical information storage unit comprising: a start edge pulse generation circuit which generates a start edge pulse having a constant width at a start edge position of the high period of the data; a burst gate generation circuit which generates a burst gate signal at a middle position of the mark when the high period of the data is long and which generates no burst gate signal when the high period of the data is short; an end edge pulse generation circuit which generates an end edge pulse having a constant width at an end edge position of the high period of the data; a mark/space length detection circuit which generates an nT mark signal including said start edge pulse and said end edge pulse when the high period of the data has n clocks and which generates an mT mark signal including said end edge pulse and said start edge pulse of both edges of the space when the low period of the data has m clocks (where n and m are natural numbers existing in a data string); an encoder which generates a select signal, which is for controlling a start edge selector to be described later and an end edge selector to be described later, from said nT mark signal and said mT mark signal; a cooling-pulse generation circuit which generates a cooling pulse having a constant width from an end edge pulse which was output from said end edge pulse generation circuit; the start edge selector which selects and outputs one from a plurality of start edge values by said selector signal; a start edge sample/hold circuit which updates a start edge set value output of said start edge selector only when said start edge pulse appears and which holds a previous value when no start edge pulse appears; a programmable start edge delay line which varies a quantity of delay by the start edge set value of the output of said start edge sample/hold circuit and which outputs a delayed start edge pulse where said start edge pulse is delayed; the end edge selector which selects and outputs one from a plurality of end edge values by said selector signal; an end edge sample/hold circuit which updates an end edge set value output of said end edge selector only when said end edge pulse appears and which holds a previous value when no end edge pulse appears; the programmable end edge delay line which varies a quantity of delay by the end edge set value of the output of said end edge sample/hold circuit and then delays said end edge pulse and which outputs a delayed end edge pulse where said end edge pulse is delayed; a cooling-pulse delay line which varies a quantity of delay of the cooling pulse, which is output from said cooling-pulse circuit, and outputs a delayed cooling pulse; an AND gate which performs a logical product between the burst pulse from said burst gate generation circuit and the clock and outputs a burst pulse; an OR gate which performs a logical sum between said delayed start edge pulse, said burst pulse, and said delayed end edge pulse and outputs a recording signal; an inverter which inverts the delayed cooling-pulse signal which is from said cooling-pulse delay line; a bias current source which supplies a bias current of a laser diode to be described later; a recording-current source which supplies a recoding current of the laser diode in parallel with said bias current source; a light-reproducing current source which supplies a light reproducing current of the laser diode in parallel with said bias current source; a switch which turns the current of said recording-current source on and off by said recording current; a switch which turns the current of said bias current source on and off by said cooling pulse signal; and the laser diode which records disk signals driven in parallel by said bias current source, said recording-current source, and said light-reproducing current source.

Claim 31

In an optical information recording method which switches and irradiates laser light having a plurality of powers onto an optical storage medium having a thin storage film which changes reversibly between optically recognizable states, and which overwrites a digital signal having modulated pulse widths by employing a light beam, the optical information recording method wherein: a record mark is formed by irradiating laser light by a recording waveform which comprises pulses where said laser light is modulated between at least three powers: a recording power which records said thin storage film, a bias power lower than said recording power, and a cooling power lower than said bias power; the laser light is irradiated between said record marks by said bias power; and a laser light irradiation period at said bias power is provided between the laser light irradiation at said recording power and the laser light irradiation at said cooling power.

Claim 32

In an optical information recording method which switches and irradiates laser light having a plurality of powers onto an optical storage medium having a thin storage film which changes reversibly between optically recognizable states, and which overwrites a digital signal having modulated pulse widths by employing a light beam, the optical information recording method wherein: a record mark is formed by irradiating laser light by a recording waveform which comprises pulses where said laser light is modulated between at least three powers: a recording power which records said thin storage film, a bias power lower than said recording power, and a cooling power lower than said bias power; the laser light is irradiated between said record marks by said bias power; a laser light irradiation period at said bias power is provided between the laser light irradiation at said recording power and the laser light irradiation at said cooling power; and laser light irradiation start time at said cooling power with respect to an end point of said recording power is varied according to a radial position of said optical storage medium.

Claim 33

The optical information recording method as set forth in claim 32, wherein, the irradiation start time at said cooling power is quickened in a region of said optical storage medium inside at least a predetermined radius than in a region outside said predetermined radius.

Claim 34

In an optical information recording method which switches and irradiates laser light having a plurality of powers onto an optical storage medium having a thin storage film which changes reversibly between optically recognizable states, and which overwrites a digital signal having modulated pulse widths by employing a light beam, the optical information recording method wherein, in the case where a record mark is formed by irradiating laser light by a recording waveform which has a recording pulse train, comprising a plurality of pulses where said laser light is modulated between a first power previously set to a power greater than a recording power for recording said thin storage film and a second power previously set to a power lower than said first power, and which also has, after said recording pulse train, a cooling pulse which irradiates laser light by a cooling power lower than a bias power where the laser light power is less than said recording power, said recording waveform has a period where the power of the laser light varies by stages or continuously between said cooling power and said bias power.

Claim 35

In an optical information recording method which switches and irradiates laser light having a plurality of powers onto an optical storage medium having a thin storage film which changes reversibly between optically recognizable states, and which overwrites a digital signal having modulated pulse widths by employing a light beam, the optical information recording method wherein, in the case where a record mark is formed by irradiating laser light by a recording waveform which has a recording pulse train, comprising a plurality of pulses where said laser light is modulated between a first power previously set to a power greater than a recording power for recording said thin storage film and a second power previously set to a power lower than said first power, and which also has, after said recording pulse train, a cooling pulse which irradiates laser light by a cooling power lower than a bias power where the laser light power is less than said recording power, said cooling pulse comprises a pulse train having a plurality of pulses where said bias power and said cooling power are alternately repeated and formed.