Abstract: An optical slip ring system (1) has a rotor interface (2) which can bolt on to a high speed rotor in a modular manner. The rotor interface (2) has circular circuit boards (7) containing the necessary drive circuits and power supply circuits for transducers mounted on the rotor. The drive circuit on the boards (7) drive three rings of emitter LEDs (9). The drive is frequency modulated and there are a number of transducers associated with each ring of emitter LEDs (9). These signals are frequency division multiplexed to ensure real time processing takes place. A fixed support (3) has a single receiver LED (15) associated with each ring of emitter LEDs (9). Contactless power is provided by an inductive power supply having a primary winding (16) on the fixed support bracket (3) and a secondary winding (10) on the rotor interface (2).

Abstract: A dental floss device (1, 40, 50, 60, 70) comprises a handle (2) having a shank (3) terminating in a head piece (4). A disposable dental floss holder (5) comprises a base portion (10) and a pair of spaced-apart jaws (11, 12) with a length of dental floss (13) extending therebetween. The head piece (4) has a groove (20) in which the base portion (10) is securely retained when the device is used in all flossing directions. Snap-fit projections (15) extend inwardly from the jaws (11, 12) of the floss holder (5) and are retained behind marginal edges (25) of a floor (24) of the groove (20). When used, the floss holder (5) is removed and a new floss holder (5) is fitted.