In a recording technique in which a plurality of light spots are simultaneously formed by using an ultra-short pulse laser and a spatial phase modulator, and a plurality of recording dots having refractive indexes different from those of the vicinities thereof are formed inside a recording medium, it is hard to make recording quality and a recording density compatible. Therefore, a plurality of dots are recorded at a predetermined dot pitch, and then other dots are recorded between the recorded dots.

In a recording technique in which a plurality of light spots are simultaneously formed by using an ultra-short pulse laser and a spatial phase modulator, and a plurality of recording dots having refractive indexes different from those of the vicinities thereof are formed inside a recording medium, it is hard to make recording quality and a recording density compatible. Therefore, a plurality of dots are recorded at a predetermined dot pitch, and then other dots are recorded between the recorded dots.

Methods and apparatus for archival storage of an image are disclosed. The image is converted into one or more bit plane images. Fiducial markers are generated and written onto digital optical tape concurrent with writing the one or more bit plane images onto the digital optical tape.

Methods and apparatus for archival storage of an image are disclosed. The image is converted into one or more bit plane images. Fiducial markers are generated and written onto digital optical tape concurrent with writing the one or more bit plane images onto the digital optical tape.

In a case where (i) a reflectance calculated from a reflected light amount obtained from a longest pit (P1max) or a longest space (S1max) in a first pit row is defined as a first reflectance and (ii) a reflectance calculated from a reflected light amount obtained from a longest pit (P2max) or a longest space (S2max) in the second pit row is defined as a second reflectance, the first pit row is formed such that the first reflectance becomes substantially identical with the second reflectance.

A reproducing device (100) includes (i) an optical pickup (6) for irradiating, with reproduction light, an optical disk (1) which is a super-resolution medium, (ii) an RF signal processing circuit (9) for converting, into a reproduction signal, light which reflected off optical disk (1), (iii) an i-MLSE detecting section (141) for evaluating quality of the reproduction signal, and (iv) a spherical aberration correcting section (142) for correcting a spherical aberration by using a result of evaluation of the quality of the reproduction signal.

In a case where (i) a reflectance calculated from a reflected light amount obtained from a longest pit (P1max) or a longest space (S1max) in a first pit row is defined as a first reflectance and (ii) a reflectance calculated from a reflected light amount obtained from a longest pit (P2max) or a longest space (S2max) in the second pit row is defined as a second reflectance, the first pit row is formed such that the first reflectance becomes substantially identical with the second reflectance.

An optical disk (100) of the present invention includes (i) a medium information region (101) (a) in which type identification information is recorded by recesses and/or protrusions which are formed by a given modulation method and whose lengths are longer than a length of an optical system resolution limit of a playback device and (b) in which first address information is recorded in a first address data format and (ii) a data region (102) (a) in which content data is recorded by recesses and/or protrusions which are formed by the given modulation method and which include a recess and/or a protrusion whose length is shorter than the length of the optical system resolution limit and (b) in which second address information is recorded in a second address data format.

An optical disk (100) of the present invention includes (i) a medium information region (101) (a) in which type identification information is recorded by recesses and/or protrusions which are formed by a given modulation method and whose lengths are longer than a length of an optical system resolution limit of a playback device and (b) in which first address information is recorded in a first address data format and (ii) a data region (102) (a) in which content data is recorded by recesses and/or protrusions which are formed by the given modulation method and which include a recess and/or a protrusion whose length is shorter than the length of the optical system resolution limit and (b) in which second address information is recorded in a second address data format.

In a multilayer optical disc having information layers conforming to a plurality of different optical disc standards, because the type of each information layer is not recorded in the other information layers, in read and write operations by a compatible optical disc device conforming to a plurality of optical disc standards, every time the information layer being accessed changes, it has been necessary to read the type of the information layer and select a method of generating a tracking error signal adapted to the type of information layer, so access has taken time. In order to solve the above problem, in the optical multilayer disc according to the present invention, having information layers conforming to a plurality of different optical disc standards, in an area in one of the information layers, information about the other information layers is recorded. The time required to access the other information layers can be reduced by using this information to select a tracking error signal generating method.