A dot array fluorescent tube for an optical printer writes optical information on a photoconductive element by converting an information signal representative of a desired image to optical information. A grid electrode disposed in a vacuum space defined in a housing has a slot-like opening in a portion thereof which faces an array of fluorescent elements which are formed on anodes, which are also arranged in an array in the lengthwise direction of the housing. The grid electrode is formed as a metal film on the housing through an insulating layer. A conductive light intercepting film is deposited on the housing except for a limited portion which faces the fluorescent element array, thereby regulating the direction of light which is transmitted through the housing. The fluorescent elements in the array provide a plurality of dot arrays which are controlled independently of each other. Lead terminals are connected with the anodes and led out to the outside of the housing to be connected to external drive devices by an anisotropic conductive rubber connector. The lead terminals are divided into groups each made up of a predetermined number.