Optical information reproducing apparatus and optical information reproducing method

An optical information reproducing apparatus comprising:

• an irradiation section to irradiate a light beam onto an optical information recording medium, in which a plurality of holes are formed along a virtual track on a recording medium, along the virtual track according to encoded information;
• a light receiving section to receive a reflected light beam when the light beam is reflected by the optical information recording medium and to sequentially generate a light receiving signal corresponding to light intensity;
• a detection section to detect a first variation pattern appearing when a signal level of the light receiving signal changes according to a first hole of the plurality of holes and a second variation pattern appearing when a signal level of the light receiving signal changes according to a second hole of the plurality of holes;
• and
• a code string generating section to generate a code string based on the first and second variation patterns,
• wherein the first variation pattern does not exceed a threshold and the code string generating section generates a first code based on the first variation pattern, the first code including a first bit, and
• wherein the second variation pattern exceeds the threshold and the code string generating section generates a second code based on the second variation pattern, the second code including a plurality of bits representing a second plurality of holes.