Abstract: A triggering system for a stroboscope system, comprising: a light source for projecting light on a vibratory object, such as vocal folds, an optical sensor for sensing light reflected or transmitted from said vibratory object in response to the projected light, in order to obtain vibratory information from the vibratory object; and a control arrangement connected to the optical sensor, for converting the vibratory information into triggering signals for the stroboscope system, said electronic control arrangement including a control output connectable to said stroboscope system, for outputting said triggering signals to said stroboscope system.

Abstract: An image intensifier tube device including a plurality of diode image intensifier tubes. Each tube comprises a sealed cylindrical envelope having its one end closed by an entry window carrying a photo-sensitive, electron emitting layer enclosed by a good electrically conductive rim. A resistive layer is deposited by vaporization between the circumference of the electron emitting layer and the good electrically conductive rim, which resistive layer is connected to a terminal of a voltage source having its other terminal connected to an anode and to focussing means of the tube such that in response to a sudden increase in the brightness of the image to be intensified a voltage drop is produced across the resistive layer, as a result of which the emitted electrons are de-focussed and/or deflected.