Abstract: A gas discharge panel in which a pair of substrates each has provided thereon a plurality of buses and a plurality of electrodes regularly connected to the buses, and in which the substrates are disposed opposite to each other with a discharge gas sealing space defined therebetween. By applying switching voltages to the buses, discharge spots between pair of opposed electrodes are sequentially shifted. No cross-over parts for electrode connections are present on the substrates.

Abstract: In conjunction with an AC plasma display panel a light detecting pen is employed to designate coordinate points on the panel. Circuitry is employed to scan the electrodes of the panel with sustain voltage pulses at predetermined intervals and determine the coincidence of a selectively applied sustain voltage pulse with light detected by the light pen to indicate the location of the light pen with respect to the panel. A negative scanning method is also disclosed wherein coincidence between a sustain voltage pulse which is selectively not applied and the non-detection of light indicates the location.

Abstract: A drive system for an alternating current (AC) driven type gas discharge panel in which either one of the electrode pitches of X and Y electrodes is made smaller than the other. A positive pulse voltage is applied to the electrodes of the smaller electrode pitch and a negative pulse voltage is applied to the electrodes of the larger electrode pitch, thereby to write information in a selected discharge point. The AC driven type gas discharge panel of an electrode arrangement of an asymmetrical electrode pitch is driven with a maximum write margin which does not cause half select misfire.

Abstract: A zoom lens system of a color television camera is divided into a front lens component comprising a zooming lens system and a front part of a relay lens system, and three equivalent rear lens components each comprising a rear part of the relay lens system. A color separating prism system is located between the front and the rear parts of the relay lens system. The rear lens components are convergent so that the angle of light beams incident into the prism system may be smaller than that of the light beam incident into the image pick-up tubes.