Tinted tape cassette having an optical tape sensing construction

Claim 1

A tinted tape cassette adapted to operate with an apparatus having optical tape-end detecting means, said cassette accommodating a magnetic tape stretched partially along a tape path, and an end of the magnetic tape being sensed optically by allowing to pass through said end a light emitted and received by said optical tape-end detecting means, said cassette comprising a housing having an upper shell, a lower shell and a guard panel, at least one transparent window means provided in said upper shell to thereby make the magnetic tape visible outside the cassette, said window means comprising an agent which absorbs near-infrared rays from the light incident to said window, said housing being made of a housing material comprising a resin, 0.1 to 0.25 weight percent of carbon black, and a coloring material other than carbon black, said coloring material providing a tinted color to said housing material, said housing having a light path along which said light travels, said housing material having the characteristic in which the transmittance of light is lower thant 0.05 percent when the thickness of the housing material is 0.05 millimeter, said housing material having a reflectivity which is lower than about 7 percent for a wavelength range of 400-1100 nanometers such that said housing material prevents undesired light from being transmitted through the housing material to said optical tape-end detecting means to thereby preclude erroneous actuation of said optical tape-end detecting means.