PURPOSE: To improve a freedom degree of a shape and enhance visibility of an indicating direction by providing a picture symbol in such a position as to be identified in the order of direction indication, and controlling to apply or stop a predetermined voltage to a plurality of planar electrodes according to the disposing order.
CONSTITUTION: An emergency DC power source 13 is supplied with electric power via a charger 12 under a normal condition, namely, it is always charged. All of switches 15a-15c are closed by a control circuit 18, and a DC of the emergency DC power source 13 is converted into a high frequency AC of, e.g. 20kHz by an inverter 14 so as to be applied to electrodes 9a-9c. A voltage is supplied to xenon gas staying inside a vacuum glass container 6 via a glass as a dielectric which is brought into contact with the electrodes 9a-9c, thus generating electric discharge. Since an ultraviolet ray generated by the electric discharge excites a phosphor 7 formed on the inner wall of the vacuum glass container 6, emits visible light having a wave length peculiar to the phosphor 7, and outputs a visible beam from the front surface of an output unit 9, a display unit 6 is lit as a whole, i.e., the entire arrow mark is lit.
YANAGIMACHI HIROYUKI
YAMAZAKI HIROYOSHI
ISHII TAKAMICHI
