Information record medium, apparatus for recording the same and apparatus for reproducing the same

摘要

An information record disk comprising: a lead-in area; a recording information area for storing record information at a variable rate, the record information being readable by an information reproducing apparatus; and a control information area in the lead-in area for storing control information which is readable by an information reproducing apparatus, the information record disk characterized in that the control information includes physical format information indicating a physical structure of the information record disk, and the physical format information includes reading rate information, the reading rate information indicating any one of a plurality of predetermined reading rates of the record information or a status that reading rate of the record information is not specifically prescribed.