Optical disc for tuple-speed recording and optical disc device for tuple-speed recording

An optical disc device for recording information on a recordable optical disc, comprising:

• an optical pickup that irradiates the optical disc with laser light;
• a disc drive unit that rotationally drives the disc;
• a servo unit that controls the optical pickup and the disc drive unit;
• an information recording unit that records information on the disc through the optical pickup at a predetermined speed and is capable of changing a recording speed of the information if desired;
• and
• an information reproduction unit that reproduces information from the disc through the optical pickup, wherein
• the optical disc includes:
• a read-only system area;
• and
• a recordable data area, and
• disc boundary information representing a boundary in a radial direction of an area on which capability of recording at a predetermined recording speed is based on a test, performed by a disc manufacturer, for a recording characteristic with respect to the optical disc, is recorded on the system area while being related to speed information on the recording speed, and
• the information recording unit, upon an instruction of recording at a first recording speed, compares the boundary related to the first recording speed with a present recording position, performs recording at the first recording speed if the present recording position is outside of the boundary, and performs recording at a second recording speed lower than the first recording speed if the present recording position is inside of the boundary, wherein the information recording unit further holds drive boundary information that represents a boundary in a radial direction of an area set as being capable of being recorded on at a predetermined recording speed, while relating the drive boundary information to the speed information on the recording speed, and, upon an instruction of recording at the first recording speed, performs recording at a third recording speed lower than the first recording speed, if the present recording position is on an inside of the boundary of the first recording speed based on the drive boundary information even if the present recording position is not on an inside of the boundary of the first recording speed based on the disc boundary information.