Information recording carrier and method of reproducing the same
View Patent ↗An information recording carrier according to one embodiment has minute pattern including plural grooves or lands formed to be substantially in parallel and adjacent each other and comprises a supporting body having the minute pattern, a recording layer formed on the minute pattern formed on the supporting body and a light transmission layer formed on the recording layer. The minute pattern is formed under a relation of P<λ/NA, where a pitch of each groove or land is P, a wavelength of a laser beam is λ and a numerical aperture of an objective lens is NA. The plural grooves or lands have at least a wobbling region and data is recorded wobblingly in the wobbling region by frequency shift modulation. A phase relation between a high frequency portion and a low frequency portion composing the frequency shift modulation is ±(π/20.5) to ±(π/0.751).
1. An information recording carrier having minute pattern including plural grooves or lands formed to be substantially in parallel and adjacent each other,
wherein when a pitch of each groove or land is P, a wavelength of a laser beam is λ and a numerical aperture of an objective lens is NA, the minute pattern is formed under a relation of P<λ/NA;
wherein the plural grooves or lands include at least a wobbling region and data is recorded wobblingly in the wobbling region by frequency shift modulation;
wherein digital recording using the frequency shift modulation is carried out by frequency shift modulation in which with a predetermined frequency having either of 1-100 waves as a channel bit, the frequency is changed over for each channel bit; and
wherein a phase relation between a high frequency portion and a low frequency portion composing the frequency shift modulation is ±(π/20.5) to ±(π/0.75).
2. A method of reproducing an information recording carrier as recited in claim 1 , comprising:
irradiating the laser light on the recording layer through the light transmission layer in such a way that the laser light tracks the grooves or lands therebeneath;
detecting the laser light reflected by the recording layer; and
recognizing the frequencies that are used in frequency shift modulation through the detected laser light.
3. The information recording carrier as recited in claim 1 , further comprising:
a supporting body having the minute pattern thereon:
recording layer formed on the minute pattern; and
a light transmission layer formed on the recording layer.