Abstract: A dual flash array, each alternately connectible to a flashing circuit, having indicators associated with each flash device includes automatic masking devices which mask the indicators associated with the flash array not in the firing circuit.

Abstract: A flash array which is provided with a transparent electrically conductive layer which serves to prevent spontaneous ignition of a flash lamp in the device. The flash array is provided with high voltage combustion flash lamps and the transparent electrically conductive layer consisting of conductive indium oxide which is applied to the inner side of a transparent cover of the array. The resistance per square of that layer is smaller than 100 kOhm, so that for these lamps -- which are, for example, ignited by means of a piezo element -- substantially no spontaneous ignition occurs.