Optical high density FM recording device with corrective signal
AssigneeCanon Kabushiki Kaisha
InventorsTakao Tsuji, Takeshi Goshima, Hideaki Sato
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Abstract
An optical high density recording device which comprises, in combination, a beam generator, a beam modulator to modulate the beam in accordance with an applied modulating signal, a recording medium to record a locus of the beam irradiated thereonto. The recording medium and the beam irradiated onto the recording medium are moved relatively to one another, a recording signal is introduced onto the recording medium, a corrective voltage to be determined by a function of the recording signal is generated and is applied with the recording signal to the beam modulator as a modulating signal.
Claims7
An optical high density recording device comprising:
- (a) laser beam modulating means for forming a laser beam modulated in accordance with a modulating signal applied thereto;
- (b) a recording medium onto which the modulated laser beam obtained from said laser beam modulating means is irradiated, wherein the beam-irradiated portions of said medium are recorded in the form of undulations in accordance with the irradiated beam;
- (c) means for moving said recording medium and the beam irradiated onto said recording medium relative to one another;
- (d) a video signal generating means for generating a frequency-modulated video signal;
- (e) processing means connected to said video signal generating means for generating a corrective signal having a corrective voltage corresponding to the frequency of said frequency-modulated video signal to make the height of said undulations constant when the frequency of said frequency-modulated video signal exceeds a particular frequency;
- and
- (f) adding means for adding an output from said video signal generating means and an output from said processing means to form a modulating signal for application to said modulating means.
An optical high density recording device comprising:
- (a) laser beam modulating means for forming a laser beam modulated in accordance with a modulating signal applied thereto;
- (b) a recording medium onto which the modulated laser beam obtained from said laser beam modulating means is irradiated, wherein the beam-irradiated portions of said medium are recorded in the form of undulations in accordance with said irradiated beam;
- (c) means for shifting said recording medium and the beam irradiated onto said recording medium relative to one another;
- (d) a video signal source for generating a video signal;
- (e) frequency modulating means for modulating the frequency of the video signal output from said video signal source;
- (f) delay means for delaying the frequency modulated video signal output from said frequency-modulating means;
- (g) processing means connected to said frequency-modulating means for generating a corrective signal having a corrective voltage corresponding to the frequency of said frequency-modulated video signal to make the height of said undulations constant when the frequency of said frequency-modulated video signal exceeds a particular frequency;
- and
- (h) adding means for adding an output from said delay means and an output from said processing means to form a modulating signal for application to said modulating means.
Dependencies are inferred from the claim text.