摘要:
A CD player capable of detecting the recording end of a partially recorded CD-R (PRD) during playback. When an unrecorded area (URA) is detected, an address immediately before that of the URA is held and a setup is performed at the position of that detection. If the setup has been unsuccessful, a setup is performed at a reference setup position, and when this setup operation is complete, playback starts from the held address position. When the playback from the position and detection of the URA are repeated a predetermined number of times, the held address position is discriminated as the recording end. A method of searching for the last piece of recorded information in the program area on a PRD. When reading failure occurs in a search, the pickup is moved back to a previous jump position to the position of occurrence of the reading failure, then a search is conducted through jumps over tracks equal to or less in number than the number of tracks of the predetermined smallest information from that jump position, and the last piece is detected by a sub code acquired at a jump position immediately previous to the position of re-occurrence of reading failure. A CD player capable of ensuring reproduction of all the pieces of recorded information in playback of a PRD. When detecting a next track number in an area following an area of a memorized last track number during playback of a PRD, this player updates the last track number to the newly detected track number.
摘要:
There is provided an optical recording medium (1) including a first pit string having a succession of pits (P) and mirror surface sections (M), which first pit string is formed on one side of a track center (Tc) as a reference, and a second pit string having pits (P) and mirror sections (M), reversed in their array from the pits (P) and the mirror surface sections (M) of the first pit string. A laser beam (L) is radiated onto the track center (Tc) for accessing information signals represented by the pits (P) and the mirror surface sections (M). There are also provided a recording device and a reproducing device for such optical recording medium (1).
摘要:
In an optical disk having a recording plane having a spiral first track and a spiral second track, information being to be recorded into and/or reproduced from said first and second tracks, the first track is formed into a groove-like shape, the second track is formed between adjacent the first tracks and into a land-like shape, and the first and second tracks record informations in different modulation methods.
摘要:
A disk reproducing apparatus is provided which can cope with the intermittent access due to track jump in the conventional CD reproducing system and which can reproduce data at N times the normal speed and produce the reproduced data at the normal speed. The disk reproducing apparatus includes a memory (11) for storing the data and time information reproduced from the disk to match with each other, another external memory (15), a detection circuit (10) detecting the time difference between the finally produced output data and the data which is being accessed, and a control circuit (19) detecting the overflow/underflow of the external memory (15) and controlling it to be written. The construction can absorb the time difference between the system operation speed and data output speed even during an intermittent access so that continuous data can be produced.
摘要:
To execute high speed searching rapidly and accurately, the apparatus is provided with recording means (13 to 17) for measuring the difference ε between the address represented by subcode Q data recorded on the information data-recording region of a CD-ROM disk (11) and the address represented by header address data and for recording the difference ε thus measured correspondingly on the information data regions, and correcting means (18 and 19) for correcting the position where a pick-up (12) is to be moved in accordance with the difference ε by setting a target position where the pick-up (12) is to be moved by using the address represented by the subcode Q data and by reading from the recording means (13 to 17) the difference ε of the information data recording region including the target position when search is requested for the information data recorded on the information recording region.
摘要:
A disc recording apparatus for recording data such as information concerning musical performance on a recording disc (1) to which absolute addresses have been imparted in advance. Vibration during the recording operation and unexpected track jump due to defect in the recording disc are detected relying upon the discontinuity of absolute addresses reproduced from the recording disc (1). In case the track jumping has taken place, the laser power of the optical head (12) is dropped to the reproduction level and the track jump control is effected to give access to a desired track. The recording operation is then resumed for the track.
摘要:
Un procédé permet de réduire le temps d'accès nécessaire pour atteindre un point voulu d'une piste de données d'un disque en rotation. Lorsque le dispositif de balayage d'un appareil de reproduction saute rapidement plusieurs pistes de données d'un disque, il ne peut parvenir avec précision que sur une piste. Dans le cas le plus défavorable, pour que le point voulu sur la piste voulue soit détecté par le faisceau de lumière du dispositif de balayage, il faut attendre jusqu'à ce que le disque (CD) ait effectué une rotation complète. Dans un lecteur CD à vitesse linéaire constante, ce temps d'attente supplémentaire est compris entre 120 ms et 330 ms. Afin de réduire ce temps d'accès, la vitesse de rotation du disque requise pour que le point voulu (P2) soit détecté lorsque la piste voulue (S2) est atteinte est calculée à partir du nombre A de pistes situées entre la piste de données (S1) balayée en dernier et la piste voulue (S2), à partir des positions angulaires du point (P1) balayé en dernier sur la piste de données (S1) balayée en dernier et du point voulu (P2) sur la piste voulue (S2), ainsi qu'à partir de la durée du saut. L'invention a des applications dans des appareils de reproduction et/ou d'enregistrement qui balaient sans contact un disque en rotation, par exemple des lecteurs de disques compacts, des lecteurs de disques vidéo, des lecteurs de disques DRAW et d'autres appareils magnéto-optiques.