US5642343A — Magnetooptic disc apparatus and recording medium

Claim 1

Independent Claim 295 words

An optical disc apparatus comprising: a light source for irradiating a light beam to an optical disc; an encoder for converting an information signal to be recorded into a code train; light source driving means for modulating the light beam in accordance with said code train, for irradiating the light beam as a light pulse train to the optical disc, and for recording the code train as recording marks by at least one of a heat function and heat interference; a detector for photoelectrically converting the light reflected from said optical disc, thereby obtaining an electric signal waveform; waveform processing means for processing said electric signal waveform; pulse forming means for obtaining a pulse signal from a signal from said waveform processing means; a discriminator for detecting the code train recorded on the optical disc from said pulse signal; a decoder for decoding the code train from said discriminator into the information signal; trial writing means for modulating the light beam by a special test signal and for forming a test pattern onto the optical disc; means for reproducing the test pattern and for evaluating output waveforms of the test pattern thus reproduced; and control means for controlling the modulation of the light beam on the basis of results obtained in the evaluation; wherein said light source driving means irradiates light beams of at least three power levels, including a first power level (P w ) for recording said recording marks, a second power level (P as ) just before the recording of said recording marks by said first power level, and a third power level (P r ) just after the recording of said recording marks by said first power level, and wherein said control means controls a value of said second power level.

Claim 2

Dependent Claim 295 words

An optical disc apparatus comprising: a light source for irradiating a light beam to an optical disc; an encoder for converting an information signal to be recorded into a code train; light source driving means for modulating the light beam in accordance with said code train, for irradiating the light beam as a light pulse train to the optical disc, and for recording the code train as recording marks by at least one of a heat function and heat interference; a detector for photoelectrically converting the light reflected from said optical disc, thereby obtaining an electric signal waveform; waveform processing means for processing said electric signal waveform; pulse forming means for obtaining a pulse signal from a signal from said waveform processing means; a discriminator for detecting the code train recorded on the optical disc from said pulse signal; a decoder for decoding the code train from said discriminator into the information signal; trial writing means for modulating the light beam by a special test signal and for forming a test pattern onto the optical disc; means for reproducing the test pattern and for evaluating output waveforms of the test pattern thus reproduced; and control means for controlling the modulation of the light beam on the basis of results obtained in the evaluation; wherein said light source driving means irradiates light beams of at least three power levels, including a first power level (P w ) for recording said recording marks, a second power level (P as ) just before the recording of said recording marks by said first power level, and a third power level (P r ) just after the recording of said recording marks by said first power level, and wherein said control means controls a value of said second power level.

Claim 3

Dependent Claim 29 words

An optical disc apparatus according to claim 1, wherein the test pattern formed by the trial writing means is encoded by the encoder and recorded on the optical disc.

Claim 4

Dependent Claim 31 words

An optical disc apparatus according to claim 1, further comprising a change-over switch for supplying the electric signal waveform into the pulse forming means without passing through the waveform processing means.

Claim 5

Dependent Claim 48 words

An optical disc apparatus according to claim 1, wherein the light pulse train comprises a plurality of units, one unit forming one of the recording marks comprising a head pulse and a subsequent pulse train whose time width differs from that of said head pulse. P.sub.w >P.sub.as >P.sub.r.

Claim 6

Dependent Claim 27 words

An optical disc apparatus according to claim 4, wherein at least one of the pulse widths and the pulse intervals of the subsequent pulse train are equal.

Claim 7

Dependent Claim 57 words

An optical disc apparatus according to claim 1, further comprising means for controlling edge positions of the pulses constituting the light pulse train on the basis of at least one of a temperature of the optical disc, a recording linear velocity to the optical disc, and the recording mark based on the information signal to be recorded.

Claim 8

Dependent Claim 22 words

An optical disc apparatus according to claim 6, further comprising table means for storing information in tables to control the edge positions.

Claim 9

Dependent Claim 33 words

An optical disc apparatus according to claim 1, wherein the result of the comparison reflects at least one element which is selected from the width, length, and mark interval of the recording mark.

Claim 10

Dependent Claim 67 words

An optical disc apparatus according to claim 1, wherein a recording clock is used to control at least one of the pulse width and the pulse interval of the pulses constructing said light pulse train, and is set to a value which is a fraction of an integer of or is integer times as large as a detection window width which is formed by said recording clock.

Claim 11

Dependent Claim 32 words

An optical disc apparatus according to claim 1, wherein said first power level is larger than said second power level, and said second power level is larger than said third power level.

Claim 12

Dependent Claim 298 words

An optical information recording and reproducing method comprising the steps of: converting an information signal to be recorded into a code train; modulating a light beam into a light pulse train in accordance with said code train; irradiating the light pulse train onto a recording medium; recording the code train as recording marks by at least one of a heat function and heat interference of the light pulse train; photoelectrically converting the light from the recording medium to thereby obtain an electric signal waveform; processing said electric signal waveform; converting a signal obtained by processing said electric signal waveform into a pulse signal; detecting the code train recorded on the recording medium from the pulse signal; decoding the detected code train to the information signal; modulating the light beam by a special test signal; forming a test pattern on the recording medium; reproducing the test pattern; and evaluating output waveforms of the reproduced test pattern; wherein a unit of the light pulse train for forming one of said recording marks has pulses of power levels equal to or larger than a first level P w , wherein a light pulse train which does not form said recording marks has pulses of power level equal to or smaller than a second value P as , wherein said light pulse train for forming said recording marks has a region of a power level which is equal to or smaller than a third value P r that is at least one of before and after said light pulse train for forming said recording marks, wherein P w >P as >P r , and wherein the power level P as is controlled on the basis of results obtained in the evaluation, independently of the power levels P w and P r .

Claim 13

Dependent Claim 298 words

An optical information recording and reproducing method comprising the steps of: converting an information signal to be recorded into a code train; modulating a light beam into a light pulse train in accordance with said code train; irradiating the light pulse train onto a recording medium; recording the code train as recording marks by at least one of a heat function and heat interference of the light pulse train; photoelectrically converting the light from the recording medium to thereby obtain an electric signal waveform; processing said electric signal waveform; converting a signal obtained by processing said electric signal waveform into a pulse signal; detecting the code train recorded on the recording medium from the pulse signal; decoding the detected code train to the information signal; modulating the light beam by a special test signal; forming a test pattern on the recording medium; reproducing the test pattern; and evaluating output waveforms of the reproduced test pattern; wherein a unit of the light pulse train for forming one of said recording marks has pulses of power levels equal to or larger than a first level P w , wherein a light pulse train which does not form said recording marks has pulses of power level equal to or smaller than a second value P as , wherein said light pulse train for forming said recording marks has a region of a power level which is equal to or smaller than a third value P r that is at least one of before and after said light pulse train for forming said recording marks, wherein P w >P as >P r , and wherein the power level P as is controlled on the basis of results obtained in the evaluation, independently of the power levels P w and P r .

Claim 14

Dependent Claim 82 words

An optical information recording and reproducing method according to claim 11, wherein each time the recording medium is exchanged, the light beam is modulated by the special test signal to thereby form the test pattern onto the recording medium, the test pattern is produced and compared with the test signal, and at least one of the power level, pulse width, and pulse interval of the pulses forming the light pulse train is controlled on the basis of the result of the comparison.

Claim 15

Dependent Claim 139 words

An optical information recording and reproducing method, comprising the steps of: converting an information signal to be recorded into a code train; modulating a light beam into a light pulse train in accordance with said code train; irradiating the light pulse train onto a recording medium; and recording the code train as recording marks by at least one of a heat function and heat interference of the light pulse train, wherein said light pulse train includes recording pulses corresponding to said recording marks and auxiliary pulses which do not correspond to said recording marks, wherein power levels of said recording pulses are set higher than power levels of said auxiliary pulses, and wherein shapes of said recording marks are controlled by controlling the power levels of said auxiliary pulses which are applied just before application of said recording pulses.

Claim 16

Dependent Claim 139 words

An optical information recording and reproducing method, comprising the steps of: converting an information signal to be recorded into a code train; modulating a light beam into a light pulse train in accordance with said code train; irradiating the light pulse train onto a recording medium; and recording the code train as recording marks by at least one of a heat function and heat interference of the light pulse train, wherein said light pulse train includes recording pulses corresponding to said recording marks and auxiliary pulses which do not correspond to said recording marks, wherein power levels of said recording pulses are set higher than power levels of said auxiliary pulses, and wherein shapes of said recording marks are controlled by controlling the power levels of said auxiliary pulses which are applied just before application of said recording pulses.

Claim 17

Dependent Claim 73 words

An optical information recording and reproducing method according to claim 13, further comprising, before said converting step, the steps of: recording a predetermined test pattern; reproducing said test pattern; and evaluating output waveforms of said test pattern thus reproduced, wherein said step of recording the code train as recording marks comprises a step of controlling the power levels of said auxiliary pulses on the basis of results obtained in the step of evaluating.

Claim 18

Dependent Claim 81 words

An optical information recording and reproducing method according to claim 13, wherein said recording pulses have at least a first power level P w1 and a second power level P w2 , and said auxiliary pulses have at least one pulse of a third power level P as just before said recording pulses and at least one pulse of a fourth power level P r just after said recording pulses, wherein P w1 , P w2 >P as >P r .

Claim 19

Dependent Claim 141 words

An optical information recording and reproducing method, comprising the steps of: converting an information signal to be recorded into a code train; modulating a light beam into a light pulse train in accordance with said code train; irradiating the light pulse train onto a recording medium; recording the code train as recording marks by at least one of a heat function and heat interference of the light pulse train, wherein said light pulse train includes recording pulses corresponding to said recording marks and auxiliary pulses which are irradiated before said recording pulses and used for preheating said recording medium, and wherein power levels of said auxiliary pulses are controlled; and wherein said step of recording the code train as recording marks comprises a step of providing a period having a power level lower than the power levels of said auxiliary pulses.

Claim 20

Dependent Claim 141 words

An optical information recording and reproducing method, comprising the steps of: converting an information signal to be recorded into a code train; modulating a light beam into a light pulse train in accordance with said code train; irradiating the light pulse train onto a recording medium; recording the code train as recording marks by at least one of a heat function and heat interference of the light pulse train, wherein said light pulse train includes recording pulses corresponding to said recording marks and auxiliary pulses which are irradiated before said recording pulses and used for preheating said recording medium, and wherein power levels of said auxiliary pulses are controlled; and wherein said step of recording the code train as recording marks comprises a step of providing a period having a power level lower than the power levels of said auxiliary pulses.

Claim 21

Dependent Claim 72 words

An optical information recording and reproducing method according to claim 16, further comprising, before said converting step, the steps of: recording a predetermined test pattern; reproducing said test pattern; and evaluating output waveforms of said test pattern reproduced, wherein said step of recording the code train as recording marks comprises a step of controlling the power levels of said auxiliary pulses on the basis of results obtained in the step of evaluating.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	2000-06-23	2000-12-23	2001-06-24	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2004-06-23	2004-12-23	2005-06-24	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2008-06-23	2008-12-23	2009-06-24	$7700.00	Window Closed / Lapsed

Magnetooptic disc apparatus and recording medium

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