Document Type and Number:
Japanese Patent JPS4910032
Kind Code:
A
Abstract:
A frame for a transparency and a rotatable sound track. The front face of the frame is formed with an annular cavity for rotatably supporting an annular sheet of material having a magnetizable coating and an embossed area forming a spiral sound track on the front face. The annular sheet is supported on a circular wall surrounding an opening through the frame, and the rear face of the frame is provided with a support for positioning a transparency over the opening.
Application Number:
JP3615773A
Publication Date:
January 29, 1974
Filing Date:
March 29, 1973
Export Citation:
International Classes:
G03B23/02; G03B31/06; (IPC1-7): G03B31/06