Optical storage medium, a tilt detection apparatus, and a data recording and reproducing apparatus

An optical storage medium having guide grooves with a pitch of Gp1, comprising:

• at least one of groove Gn−1 and groove Gn+1 adjacent to opposite sides of an n-th groove Gn is an intermittent groove with non-groove spaces formed therein, providing an area where groove pitch Gp2 is equivalent to greater than twice pitch Gp1;
• and satisfying
• λ/NA≧Gp1≧λ/(2·NA)
• where λ is a wavelength of a beam emitted for recording or reproducing data, and NA is the numerical aperture of the convergent system for converging the beam on the optical storage medium.

A tilt detection apparatus comprising:

• a laser light source for emitting a beam;
• a convergent system for converging the beam emitted from the light source to a small spot on a data recording medium;
• a photodetector for detecting the beam diffracted and reflected by the data recording medium, and outputting a signal according to the light quantity of the detected beam;
• and
• a signal processor for receiving a first signal and a second signal output from the photodetector and processing the received signal to output a signal related to an angle formed between the optical storage medium and optical axis of the convergent system;
• said tilt detection apparatus for use with an optical storage medium having guide grooves with a pitch of Gp1 between adjacent grooves,
• groove Gn−1 and groove Gn+1 adjacent to opposite sides of an n-th groove Gn both being intermittent grooves with nongroove spaces formed therein, providing an area where pitch Gp2 of groove Gn is equivalent to twice pitch Gp1, and satisfying
• λ/NA≧Gp1≧λ/(2·NA)
• where λ is a wavelength of a beam emitted for recording or reproducing data, and NA is the numerical aperture of the convergent system for converging the beam on the optical storage medium,
• the pitch of the groove on the optical storage medium when the first signal is obtained is Gp1, and
• the pitch of the groove on the optical storage medium when the second signal is obtained is Gp2.

A tilt detection apparatus comprising:

• a laser light source for emitting a beam;
• a convergent system for converging the beam emitted from the light source to a small spot on a data recording medium;
• a photodetector for detecting the beam diffracted and reflected by the data recording medium, and outputting a signal according to the light quantity of the detected beam;
• and
• a signal processor for receiving a first signal and a second signal output from the photodetector and processing the received signal to output a signal related to an angle formed between the optical storage medium and optical axis of the convergent system;
• said tilt detection apparatus for use with an optical storage medium having guide grooves with a pitch of Gp1 between adjacent grooves,
• an intermittent groove being formed with non-groove spaces therein, providing an area where groove pitch Gp2 is equivalent to twice pitch Gp1, and satisfying
• λ/NA≧Gp1≧λ/(2·NA)
• where λ is a wavelength of a beam emitted for recording or reproducing data, and NA is the numerical aperture of the convergent system for converging the beam on the optical storage medium,
• the pitch of the groove on the optical storage medium when the first signal is obtained is Gp1, and
• the pitch of the groove on the optical storage medium when the second signal is obtained is Gp2.

A tilt detection apparatus comprising:

• a laser light source for emitting a beam;
• a convergent system for converging the beam emitted from the light source to a small spot on a data recording medium;
• a photodetector for detecting the beam diffracted and reflected by the data recording medium, and outputting a signal according to the light quantity of the detected beam;
• and
• a signal processor for receiving a first signal and a second signal output from the photodetector and processing the received signal to output a signal related to an angle formed between the optical storage medium and optical axis of the convergent system;
• said tilt detection apparatus for use with an optical storage medium having guide grooves with a pitch of Gp1 between adjacent grooves,
• at least one of groove Gn−1 and groove Gn+1 adjacent to opposite sides of an n-th groove Gn being an intermittent groove with non-groove spaces formed therein, providing an area where groove pitch Gp2 is equivalent to greater than twice pitch Gp1, and satisfying
• λ/NA≧Gp1≧λ/(2·NA)
• where λ is a wavelength of a beam emitted for recording or reproducing data, and NA is the numerical aperture of the convergent system for converging the beam on the optical storage medium,
• the pitch of the groove on the optical storage medium when the first signal is obtained is Gp1, and
• the pitch of the groove on the optical storage medium when the second signal is obtained is Gp2.