Magnetic tape reel having a positioning mark capable of being detected using a contactless detector, tape cartridge using the same, recording and reproducing apparatus for recording and reproducing information in the tape cartridge, and information recording and reproducing method thereof

摘要

A magnetic tape reel that has a plurality of gear teeth capable of engaging with a plurality of engagement gear teeth provided with a reel engaging portion of a recording and reproducing apparatus and upon which magnetic tape can be wound, the magnetic tape reel comprising: a hub portion including a cylindrical portion upon which the magnetic tape can be wound and the plurality of gear teeth; and a positioning mark capable of being detected using a contactless detector, the positioning mark being provided for aligning a specific gear tooth A from the plurality of gear teeth with a specific engagement gear tooth B from the plurality of engagement gear teeth.