Patent EP0552764A2 successfully refreshed from Google Patents.
EP0552764A2
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An optical data recording apparatus and an optical data recording/reproducing method performing servo control of a recording light beam
Assignee: Olympus Corp
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Filing: 1993-01-21
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Granted: —
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Expires: 2013-01-21
Abstract
Abstract An apparatus performs servo control of a recording light beam by using a reproducing light beam. The reproducing light beam, which doesn't destroy the recording material of an optical card (2), is emitted from a reproducing LD (96) to the optical card (2). The position of the reproducing light beam is controlled by a control unit (152). A light beam which doesn't destroy the recording material of the optical card (2) is emitted from a recording LD (50) to the optical card (2). The position of the light beam from the recording LD (50) is detected by a recording PD (78) and the detected error signal is stored in the control unit (152). The reproducing light beam is emitted again from the reproducing LD (96) to the optical card (2) together with emitting the recording light beam, which can destroy the recording material of the optical card (2), from the recording LD (50). The position of the recording light beam is controlled by the control unit (152) based on the reflected light beam of the reproducing light beam from the optical card (2) and on the stored signal in the control unit (152).
Inventors
- 👤 Yuichiro c/o Intellectual Property Akatsuka
- 👤 Toshio c/o Intellectual Property Horiguchi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 20:52
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/002; G11B7/0033; G11B7/004; G11B7/08; G11B7/09
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
317 words
An optical data recording apparatus, which irradiates light beams to a recording medium (64) having a plurality of tracks (76) and provides at least data recording to said recording medium (64), characterized by comprising: a first light source (50) for emitting light beams including a recording light beam; a second light source (96) for emitting a light beam having power weaker than said recording light beam; error signal detection means (78, 118, 178, 180) having a track error signal detection means (128, 130, 132, 182, 184) for detecting a track error signal showing a shift between an irradiation position of a light beam sent from said second light source (96) to said recording medium (64) and a position of one of said tracks (76), and/or a focus error signal detection means (136, 138, 180) for detecting a focus error signal showing a shift between a focal position of a light beam from said second light source (96) and a position of said recording medium (64); control means (152, 200) for controlling an irradiation position and/or a focal position of said recording light beam to said recording medium (64) based on the track error signal and/or the focus error signal detected by said error signal direction means (78, 118, 178, 180); and memory means (152, 196) for storing a correction value canceling a shift of the irradiation position of said recording light beam and/or a shift of the focal position of said recording light beam, at least one of said shifts being generated when the irradiation position and/or the focal position of said recording light beam to said recording medium (64) is controlled based on only the track error signal and/or focus error signal detected by said error signal detection means (78, 118, 178, 180), and said correction value being added to the track error signal and/or to the focus error signal by said control means (152, 200).
Claim 2
Dependent Claim
31 words
An apparatus to to claim 1, characterized in that said light beam emitted from said second light source (96) is a reproducing light beam reproducing data of said recording medium (64).
Claim 3
Dependent Claim
462 words
An optical data recording apparatus, which irradiates light beams to a recording medium (64) having a plurality of tracks (76) and provides at least data recording to said recording medium (64), characterized by comprising: a first light source (50) for emitting light beams including a recording light beam; a second light source (96) for emitting a light beam having power weaker than said recording light beam; a first error signal detection means (78) having a track error signal detection means (84, 88) for detecting a track error signal showing a shift between an irradiation position of a light beam sent from said first light source (50) to said recording medium (64) and a position of one of said tracks (76), and/or a focus error signal detection means (80, 82) for detecting a focus error signal showing a shift between a focal position of a light beam from said first light source (50) and a position of said recording medium (64); a second error signal detection means (118) having a track error signal detection means (128, 130, 132, 134) for detecting a track error signal showing a shift between an irradiation position of a light beam sent from said second light source (96) to said recording medium (64) and a position of one of said tracks (76), and/or a focus error signal detection means (136, 138) for detecting a focus error signal showing a shift between a focal position of a light beam from said second light source (96) and a position of said recording medium (64); light beam control means (152) for controlling the irradiation position and/or the focal position of said light beam, which is sent from said first and/or second light source (50, 96) to said recording medium (64), based on the track error signal and/or focus error signal detected by said first and/or second error signal detection means (78, 118); memory means (152) for storing an output value of said first error signal detection means (78); and control means (152) for controlling said light beam control means (152) to control the irradiation position and/or the focal position of said light beam of said second light source (96), giving instruction of emitting a light beam from said first light source (50) to bring said memory means (152) to store the output value of said first error signal detection means (78), and reading out the value stored in said memory means (152) when said first light source emits said recording light beam to allow said light beam control means (152) to control the irradiation position and/or the focal position of said recording light beam to said recording medium (64) based on the stored value in said memory means (152) and on an output value of said second error detection means (118).
Claim 4
Dependent Claim
472 words
An optical data recording apparatus, which irradiates light beams to a recording medium (64) having a plurality of tracks (76) and provides at least data recording to said recording medium (64), characterized by comprising: a first light source (50) for emitting light beams including a recording light beam; a second light source (96) for emitting a light beam having power weaker than said recording light beam; a first error signal detection means (180, 192, 194) having a track error signal detection means (192, 194) for detecting a track error signal showing a shift between an irradiation position of a light beam sent from said first light source to said recording medium (64) and a position of one of said tracks (76), and/or a focus error signal detection means (180) for detecting a focus error signal showing a shift between a focal position of a light beam from said first light source (50) and a position of said recording medium (64); a second error signal detection means (180, 182, 184) having a track error signal detection means (182, 184) for detecting a track error signal showing a shift between an irradiation position of a light beam sent from said second light source (96) to said recording medium (64) and a position of one of said tracks (76), and/or a focus error signal detection means (180) for detecting a focus error signal showing a shift between a focal position of a light beam from said second light source (96) and a position of said recording medium (64); light beam control means (200) for controlling the irradiation position and/or the focal position of said light beam, which is sent from said first and/or second light source (50, 96) to said recording medium (64), based on the track error signal and/or the focus error signal detected by said first and/or second error signal detection means (180, 182, 184, 192, 194); memory means (196) for storing an output value of said second error signal detection means (180, 182, 184); and control means (152) for controlling said light beam control means (200) to control the irradiation position and/or the focal position of said light beam of said first light source (50), giving instruction of emitting a light beam from said second light source (96) to bring said memory means (196) to store the output value of said second error signal detection means (180, 182, 184), and reading out the value stored in said memory means (196) when said first light source (50) emits said recording light beam to allow said light beam control means (200) to control the irradiation position and/or the focal position of said recording light beam to said recording medium (64) based on the value stored in said memory means (196) and on an output value of said second error detection means (180, 182, 184).
Claim 5
Dependent Claim
66 words
An apparatus according to claim 3 or 4, characterized in that the light beam, which is emitted from said first light source (50) after controlling said light beam control means (152, 200) to control the irradiation position and/or the focal position of a light beam from said second light source (96) to said recording medium (64), has power weaker than power destroying said recording medium (64).
Claim 6
Dependent Claim
82 words
An apparatus according to claim 3, characterized in that when said control means (152) instructs said second light source (96) to emit a light beam and bring said memory means (152) to store the output value of said first error signal detection means (78), said light control means (152) is controlled by said control means (152) to continuously control the irradiation position and/or the focal position of a light beam sent from said first light source (50) to said recording medium (64).
Claim 7
Dependent Claim
46 words
An apparatus according to claim 3, characterized by further comprising selector means (146) for selectively outputting the focus and/or tracking error signal detected by said first error signal detection means (78) and the focus and/or tracking signal detected by said second error signal detection means (118).
Claim 8
Dependent Claim
80 words
An apparatus according to claim 7, characterized in that said selector means (146) outputs the focus error signal detected by said first error signal detection means (78) or the focus error signal detected by said second error signal detection means (118) to a first output terminal, and outputs the tracking error signal detected by said first error signal detection means (78) or the tracking error signal detected by said second error signal detection means (118) to a second output terminal.
Claim 9
Dependent Claim
28 words
An apparatus according to claim 8, characterized in that said first and second output terminals are respectively connected to differential amplifiers (150, 151) each having an input terminal.
Claim 10
Dependent Claim
28 words
An apparatus according to claim 9, characterized in that the output of said memory means (152) is connected to each input terminal of said differential amplifiers (150, 151).
Claim 11
Dependent Claim
51 words
An apparatus according to claim 4, characterized by further comprising selector means (146) for selectively outputting the focus and/or tracking error signal detected by said first error signal detection means (180, 192, 194) and the focus and/or tracking error signal detected by said second error signal detection means (180, 182, 184).
Claim 12
Dependent Claim
41 words
An apparatus according to claim 11, characterized in that the output of said selector means (146) is connected to a sample and hold circuit (196) storing a value of the output of said second error signal detection means (180, 182, 184).
Claim 13
Dependent Claim
61 words
An apparatus according to claim 1, 3, or 4, characterized in that said error signal detection means (78, 118, 178, 180) or said first and second error signal detection means (78, 118, 178, 180) respectively include a plurality of photodetectors (80, 82, 84, 88, 128, 130, 132, 134, 136, 138, 182, 184, 192, 194) which are formed on a same plane.
Claim 14
Dependent Claim
32 words
An apparatus according to claim 1, 3, or 4, characterized in that a light beam sent from said second light source (96) irradiates the plurality of tracks (76) on said recording medium.
Claim 15
Dependent Claim
39 words
An apparatus according to claim 1, 3, or 4, characterized in that light beams sent from said first light source (50) and a light beam sent from said second light source (96) are focused by an objective lens (62).
Claim 16
Independent Claim
257 words
A method for optically recording and reproducing data characterized by including steps of: a first step of driving one (96) of two light sources (50, 96) to irradiate a first light beam having power, which is weaker than power destroying a data recording medium (64), to said data recording medium (64) and controlling a position of said first light beam based on a reflected light beam so said first light beam; a second step of driving the other light source (96) to irradiate a second light beam having power, which is weaker than power destroying the data recording medium (64), to said data recording medium (64) and detecting a positional error signal of said second light beam based on a reflected light beam of said first light beam; a third step of storing the positional error signal detected in said second step in memory means (152, 196); a fourth step of driving one (96) of said light sources (50, 96) driven in said first step to irradiate the first light beam, which has power weaker than power destroying the data recording medium (64), to said data recording medium (64) together with driving the other light source (50) to irradiate a third light beam, which has power capable of recording data on said data recording medium (64), to said data recording medium (64), and controlling a position of said third light beam based on the reflected light beam of said first light beam and a stored value of said memory means (152, 196) obtained in said third step.
References Cited (Backward Citations)
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