Magnetic tape cassette with light shielding member

摘要

A magnetic tape cassette for use in an apparatus having a light source (P) and a light sensor (S1, S2) for detecting a tape end by the difference of light transmittance of a tape (T). The magnetic tape cassette (AA, BB, CC) is composed of a light-shielding member (a through r) crossing a light path (L1, L2) for detecting the tape end by the difference of light transmittance of the magnetic layer portion and the leader portion to keep the light transmittance within the predetermined value even the tape (T) is thinner and has a higher light transmittance.