Abstract: An optical fiber connector is comprised of an optical cable and a pair of plugs connected to input and output end portions of the optical cable. A multi-fiber core employed in the optical fiber cable is constituted by a plurality of fiber cores. The input and output end portions of the optical cable are bent at an angle of about 90 while having a bent radius at the bent top portion.

Abstract: An auditory playing device has a plurality of circular or polygonal tone plates marked with respective identification codes. Each of the tone plates has concentric dark and bright stripes that are placed, one at a time, in a recess defined in a casing substantially in any direction with respect to the recess. The casing houses an array of detectors disposed in the recess for detecting the identification code on the tone plate that is placed in the recess. A microcomputer determines whether a tone plate is placed in the recess based on signals from the detectors. When one of the tone plates is placed in the recess, the microcomputer controls a loudspeaker to produce a sound represented by the identification code on the tone plate placed in the recess. The auditory playing device can easily be handled by children and is effective to train them for sharpening their auditory senses.