Signal recording method for optical disk and apparatus therefor
AssigneeSanyo Electric Co., Ltd.
InventorsMasami Makino, Satoshi Sumi
Life of this patent
Estimating the term…
Abstract
A signal recording method for an optical disk and an apparatus therefor wherein a turn-off duration, during which a laser beam is turned-off, of a binary signal to be recorded on the optical disk is elongated and an irradiation duration, during which the laser beam is irradiated, of the binary signal is shortened, so that it is possible to avoid influence of thermal diffusion which is caused by irradiating the laser beam corresponding to the irradiation duration on the optical disk and to obtain a more precise reproduced signal in comparison with that obtained by prior arts.
Claims12
A signal recording method for an optical disk, comprising the steps of:
- irradiating a laser beam on a rotating optical disk for an irradiation duration corresponding to a length of one value of a binary signal to be recorded;
- non-irradiating of the laser beam on said optical disk for a turn-off duration corresponding to a length of the other value of the binary signal;
- and
- forming a mark with the length corresponding to the irradiation duration and the turn-off duration of the laser beam on said optical disk so as to record said binary signal,
- wherein the irradiation duration and turn-off duration are changes according to at least one of the length of corresponding said one value and the length of corresponding said other value of the binary signal which have been converted based on a conversion table, said conversion table including a converted value representative of a duration of an outputted turn-off signal, and
- wherein said step of forming a mark comprises the steps of:
- receiving and storing said binary signal into a storing means and outputting said binary signal from said storing means, compensating, based on said conversion table, said outputted binary signal dependent on the length of one of said value and said other value of said received binary signal, and storing a converted signal into another storing means, outputting said converted signal once stored therein into an optical modulation recording unit, and forming said mark on said optical disk based on said converted signal.
A signal recording apparatus for an optical disk, comprising:
- a laser beam for irradiating on a rotating optical disk for an irradiation duration corresponding to a length of one value of a binary input signal to be recorded by an optical modulation unit, and for non-irradiating on said optical disk for a turn-off duration corresponding to a length of the other value of the binary signal by said optical modulation unit, so that mark with the length corresponding to the irradiation duration and the turn-off duration is formed on said optical disk so as to record said binary signal, said signal recording apparatus further comprising:
- a signal converter having a first shift register means for once storing said binary signal and for outputting said binary signal once stored, a converter means operably coupled to said first shift register means for receiving said binary signal outputted from said first shift register means and for compensating the irradiation duration and the turn-off duration to another signal in accordance to at least one of the length of corresponding one value and the length of corresponding said other value of the received binary signal based on a conversion table stored in said converter means, and a second shift register means for storing and outputting the converted signal to said optical modulation unit in synchronous with an output timing of said first register means, said conversion table including a converted value representative of a duration of an outputted turn-off signal.
A signal recording apparatus for an optical disk, comprising:
- an EFM (Eight to Fourteen Modulation) encoder which is inputted a binary signal to be recorded on the optical disk, which encodes the inputted signal by applying the EFM, and which outputs a coded binary signal;
- a signal converter having a first register means for receiving and storing therein said binary signal, a converter operably coupled to said first register means for converting an irradiation signal having a duration based on a length of corresponding one value of the binary signal and a turn-off signal having a duration based on a length of corresponding the other value of the binary signal, and compensating the duration of said irradiation signal and the duration of said turn-off signal according to at least one of the length of said one value and the length of said other value of the received binary signal based on a conversion table stored in said converter, and a second register means for storing and outputting the converted signal in synchronous with an output timing of said first register means, said conversion table including a converted value representative of a duration of an outputted turn-off signal;
- and
- an optical modulation recording unit which is inputted said converted signal, and which irradiates a laser beam on the rotating optical disk corresponding to the duration of the converted irradiation signal and turn-off signal.
Dependencies are inferred from the claim text.