Abstract: An optical recording medium having a track on which data has been previously recorded, comprising on the track a plurality of data block regions each of which includes main data of a block which is divided into a predetermined number of main data pieces, each of which has data for identifying the main data, and linking regions each of which has pseudo data and is inserted between the data block regions. When the linking regions on said track are adjacent, recording patterns of the pseudo data of the adjacent linking regions are different from each other. Further provided is a recording apparatus forming the data block regions and linking regions on a recording medium.

Abstract: A recording disc and recorded information reproducing apparatus and method for immediately starting reproduction of information when a push-pull based tracking control is employed to reproduce recorded information from the recording disc. The recording disc comprises an information data area for recording recording marks which carry information data in columns, and a control data area for recording identification information indicative of a recording pattern of the recording marks in the information data area.

Abstract: A recording disk and a recording apparatus prevent illegal copying. In a reproduction control data area, pits of a pit train on a plurality of adjacent tracks are aligned in the directions which cross the tracks perpendicularly, wherein the pit train represents reproduction control data indicative of a reproduction control method to be used for reproducing information data.

Abstract: Wobbles or a wobbling characteristic (manner, shape, configuration) of a groove track formed on a recording disc represents a type of the recording disc. Therefore, a master disc used for manufacturing such recording discs can be prepared in an easy manner.

Abstract: An optical disk, a recording apparatus and playing apparatus which can record various kinds of identification information in the form of a pit train and a bar code without decreasing the data recording area for main information. Both a first data block including a pit train indicating first identification information and a second data block including a bar code indicating second identification information are formed in the recording part at the same radius.

Abstract: A multi-layered disc (D1, D2, D3) is provided with a plurality of recording layers laminated with each other in a direction of a normal line of the recording layers, in each of which an information data recording area (2, 4) for recording information data and a control data recording area (1, 3) for recording control data to control an operation of recording and/or reproducing the information data are disposed on a same plane, the control data being recorded by a CAV method over a plurality of tracks in the control data recording area. The control data recording area in each of the recording layers is disposed such that the control data recording area (1) of one of the recording layers is not superimposed with the control data recording area (3) of another of the recording layers in the direction of the normal line.

Abstract: A record medium (1) is provided with: a main body; a groove track (1G) formed on the main body, as one track for recording information onto which a light beam for recording and/or reproducing the information is irradiated; and a land track (1L) formed on the main body, which is adjacent to the groove track, as another track for recording the information onto which the light beam for recording and/or reproducing the information is irradiated. A judgment wobble (W), which has a judgment pattern to judge whether the light beam is irradiated onto the groove track or the land track, is formed on only one side wall of the groove track.

Abstract: An information recording apparatus 100, wherein record data whose length is 8 bits is modulated to code data whose length is 16 bits by using 8/16 modulation-demodulation method, and a data-sector including a plurality of the code data is recorded onto a DVD-RAM 1. In case that the last code data placed at the end-part of the data-sector is recorded onto the DVD-RAM 1, a discriminating data to used for demodulating the last code data to record data by using the 8/16 modulation-demodulation method is generated, and the discriminating data is recorded onto the DVD-RAM 1 at the place immediately after the last code data.

Abstract: A recorded information reproducing apparatus which can remove a crosstalk of a read signal read from a recording medium which was high density recorded without decreasing a recording capacity of a recording medium. The apparatus obtains a first read sample value series by reading and sampling recorded information from a track on the recording medium, obtains a second read sample value series by reading and sampling recorded information from neighboring tracks adjacent to the track, and obtains a crosstalk component by filtering processing the second read sample value series in a variable coefficient filter. A result obtained by subtracting the crosstalk component from the first read sample value series is obtained as a read sample value series. A coefficient of the variable coefficient filter is updated so that a zero-cross sample value extracted from the read sample value series is converged to zero.

Abstract: An optical disc of a sampled servo tracking method excludes unnecessary interference to wobbled pits of the servo area, whereby a tracking servo can be stably performed, a high density maintained, and a large recording capacity obtained. An optical disc in which a circular recording area comprising a plurality of concentric tracks or a spiral recording track which hold information signals including sync signals is divided into a plurality of zones bounded by circular boundary areas. The recording track is constituted by a plurality of sectors each comprising servo areas and data areas, the servo areas being located along straight lines in radial directions within the zone. The track pitch of the boundary area is made larger than the track pitch within the zone.

Abstract: An optical recording medium which is constructed in a manner such that a plurality of recording areas in which an information signal is recorded along vortical spiral tracks are arranged in a ring shape on a recording surface and a vortex direction of the spiral track of the outside recording area among the plurality of recording areas differs from that of the spiral track of the inside recording area. When the information signal is recorded to the recording medium, the first writing device executes the writing operation from the outer rim side toward the inner rim side of the spiral track of the outside recording area and the second writing device executes the writing operation from the inner rim side toward the outer rim side of the spiral track of the outside recording area.

Abstract: An object of this invention is to provide an information recording disk which allows a higher information recording density as compared with that of a conventional disk and a recorded information reproducing apparatus for reproducing information recorded therein. On the information recording disk, plurality of pits corresponding to information are formed, and furthermore a magnetic thin film is formed from soft magnetic material such as pure iron, silicon steel, permalloy, or Mn-Zn ferrite and so on.

Abstract: An optical recording medium which is constructed in a manner such that a plurality of recording areas in which an information signal is recorded along vortical spiral tracks are arranged in a ring shape on a recording surface and a vortex direction of the spiral track of the outside recording area among the plurality of recording areas differs from that of the spiral track of the inside recording area. When the information signal is recorded to the recording medium, the first writing device executes the writing operation from the outer rim side toward the inner rim side of the spiral track of the outside recording area and the second writing device executes the writing operation from the inner rim side toward the outer rim side of the spiral track of the outside recording area.

Abstract: An optical disk with tracks having a sampled servo type recording format, and comprising a preformatted servo field including a synchronous mark for synchronization detection and a data field for recording data on each track. In the optical disk, the synchronous marks are aligned in the same radial direction of the disk per track and have the edge interval longer than the maximum inversion interval of the mark for the data in the track direction, and the interval of the synchronous mark between the adjacent tracks is made smaller than the spot diameter of a reading beam. Hence, in the radial direction of the disk where the synchronous marks are present, the synchronous mark is included in the spot of the reading beam of a pickup irrespective of being on-track or off-track to make it possible to obtain substantially the same level for synchronous signals.

Abstract: An optical disc includes a signal recording track spirally formed on the surface of the optical disc, information pits formed on the signal recording track, and a plurality of non-signal regions periodically formed on the signal recording track, wherein no information pit is formed on the non-signal region.

Abstract: A recording signal y(n,t) is recorded on a track T.sub.n of an optical disc in accordance with a following equation,y(n,t)=y(n- 1,t)+x(n,t)where y(n-1,t) is a previous signal recorded on an adjacent track T.sub.n-1, x(n,t) is an original signal for a track T.sub.n, t is time, and + is a symbol expressing the exclusive or operation.

Abstract: An optical disc is provided with: a signal track formed on a signal recording surface of the optical disc; and a plurality of cross-talk detection areas each formed on a portion of the signal track and including pits for detecting a cross-talk. The signals are recorded on areas of the signal track other than the cross-talk detection areas. An apparatus for reproducing the signals recorded on the optical disk, is provided with: a device for receiving the reflected light and for generating read signals; a device for detecting the cross-talk detection areas, and for extracting signal components of the pits for detecting the cross-talk; a device for performing a predetermined operation on the extracted signal components and for generating a control signal; and a device for receiving the read signals and the control signal and for deriving a reproduced signal in which the cross-talk is eliminated.