摘要:
It is an object to minimize the effect of the reproduction transmission path characteristics or optical characteristics of an optical head, and more suitably adjust recording conditions. The recording condition optimization method of the present invention involves optimizing recording conditions in the recording of information to an optical disk (100), comprising a recording step (1103) of recording a recording pattern including a plurality of recording marks to the optical disk using specific recording conditions, a reproduction step (1102) of reproducing the recording pattern recorded in the recording step (1103), an equalization characteristics setting step (1101) of setting waveform equalization characteristics according to the recording pattern, an equalization step (1105) of using the waveform equalization characteristics set in the equalization characteristics setting step (1101) to equalize the waveform of the reproduction signal reproduced in the reproduction step (1102), and an adjustment step (1104) of using the reproduction signal whose waveform has been equalized in the equalization step (1105) to adjust the recording conditions.
摘要:
An access unit, an access method, an access program and a control unit are provided. A record medium includes a user area for recording user data which can be recorded and regenerated based on an instruction given by a user. A recording-system circuit section included in the access unit records test data based on a predetermined test condition in the user area. A regeneration-system circuit section included in the access unit reads the test data recorded in the user area by the recording-system circuit section, and a system control circuit included in the access unit refers to the test data read by the regeneration-system circuit section and adjusts an access parameter for accessing the record medium.
摘要:
An access unit, an access method, an access program and a control unit are provided which are capable of shortening the seek time of an optical head for a test record and a test regeneration. A record medium 200 includes a user area for recording user data which can be recorded and regenerated based on an instruction given by a user; a recording-system circuit section 120 records test data based on a predetermined test condition in the user area; a regeneration-system circuit section 130 reads the test data recorded in the user area by the recording-system circuit section 120; and a system control circuit 102 refers to the test data read by the regeneration-system circuit section 130 and adjusts an access parameter for accessing the record medium 200.
摘要:
There are problems that recording degradation happens, and an error occurs in reproduction unless appropriate recording pulse conditions are determined. A recording pulse controlling method according to the present invention is a recording pulse controlling method for adjusting recording pulses for recording information on a writable optical disc, which includes a mark length adjustment step and a mark position adjustment step. The mark length adjustment step is a step for adjusting a recording mark length adjustment parameter, and the recording mark length adjustment parameter is adjusted to have a value for forming a recording mark having a length closest to a predetermined recording mark length. The mark position adjustment step is a step for adjusting a recording mark position adjustment parameter after the mark length adjustment step, and the recording mark position adjustment parameter is adjusted to have a value for forming a recording mark at a position closest to a predetermined recording mark position.
摘要:
A jitter detection apparatus includes an A/D conversion section for converting an input analog signal into a plurality of discrete multiple value digital signals; a binarization section for performing binarization of the plurality of multiple value digital signals to generate a binary signal; a jitter calculation section for calculating a jitter amount based on an error between a value of a prescribed multiple value digital signal sampled at a time which is substantially the same as a time when the value of the binary signal is changed and a prescribed threshold value; a pattern detection section for detecting patterns of the binary signal before and after the time when the prescribed multiple value digital signal is sampled; and a correction section for correcting the jitter amount based on the detected pattern.
摘要:
The present invention provides a disc device capable of normally reproducing recorded information on a disc type recording medium while complementing the recorded information in a damaged portion of the recording medium with complementary information, and capable of constantly holding useful complementary information. The complementary information for complementing the recorded information in the damaged portion of the optical disc is acquired from a server and saved in a storage area of a storing unit, and the recorded information on the optical disc is reproduced while complementing the recorded information in the damaged portion with the complementary information. When a capacity of a free space in the storage area is less than a capacity necessary for saving acquired new complementary information, usefulness of the complementary information is evaluated based on time elapsed from last referenced time, a reference count, and an acquisition required expense for the complementary information saved in the storage area, the complementary information is deleted from the storage area in order of lower usefulness to enlarge the free space, and the new complementary information is saved in the free space.
摘要:
An optical disc drive according to the present invention can read and write data from/on an optical disc 100 including record tracks to write data thereon and guide tracks for guiding a light beam 40. The drive includes: an optical pickup 101 with a converging optical system to focus the light beam 40 and form a spot thereof on the optical disc 100 for reading or writing the data; a tracking control section for controlling the converging optical system of the optical pickup 101 such that the light beam spot 40 follows a selected track on the optical disc 100 rotating; and a control unit 35 for operating the tracking control section in a first mode or in a second mode. In the first mode, the tracking control section makes the light beam spot 40 follow the recording tracks. In the second mode, the tracking control section makes the light beam spot 40 follow the guide tracks.
摘要:
In an optical disc drive, a laser light source emits a laser beam having an intensity changeable with the amount of drive current supplied. A first photodetector receives the laser beam reflected from an optical disc, thereby generating a readout signal. A second photodetector receives the laser beam, generates an electric signal representing the power of the laser beam received, and outputs the electric signal as a light quantity detection signal. A feedback control loop compares the level of the light quantity detection signal with a predetermined target value and regulates the drive current such that the level of the light quantity detection signal approaches the target value. In reading data from the optical disc, the target value is changed so as to compensate for a variation of the sensitivity of the second photodetector, thereby controlling the power of the laser beam emitted from the laser light source.
摘要:
An optical disk apparatus includes a converging section for converging a light beam toward an information carrier; a moving section for moving the light beam converged by the converging section in a direction perpendicular to a surface of the information carrier; a light detector for detecting the light beam reflected by the information carrier; a convergence state detecting section for generating a convergence state signal representing a convergence state of the light beam at a convergence point on the information carrier and outputting a reproduction signal from the information carrier, based on the output from the light detector; a focus controller for driving the moving section to make the convergence state constant based on the convergence state signal and a prescribed target position; a reproduction quality signal detector for detecting a reproduction quality signal representing a quality of the reproduction signal based on the reproduction signal; a reproduction quality signal measuring section for changing the target position and measuring a value of the reproduction quality signal corresponding to each of the changed target positions; a reproduction quality signal characteristic determining section for determining a characteristic of the reproduction quality signal based on the value of the reproduction quality signal corresponding to each of the changed target positions; and a target position searching section for searching for an optimum target position of the focus controller for optimizing the value of the reproduction quality signal based on a determination result of the reproduction quality signal characteristic determining section.
摘要:
A multivalued information reproducing apparatus includes: a light source which emits a linear polarized light having a prescribed polarization direction; a first optical system which generates a first linear polarized light and a second linear polarized light that have different polarization directions using the linear polarized light which is emitted from the light source and makes the two polarized lights input to an optical recording medium in which the polarization directions of recording lights are recorded as multivalued information; a second optical system by which light that passes the optical recording medium or light that is reflected by the optical recording medium is directed to a photo detecting portion in a state where the first linear polarized light and the second linear polarized light are separated; and a polarization direction judging portion which judges the polarization direction that is recorded in the optical recording medium based on amount of light of the first linear polarized light and amount of light of the second linear polarized light that are obtained by the photo detecting portion.