Message character image projection control system

In a message character image projection control system including an array of character shaped light forming windows, a source of light and means for exposing, selectively, windows of said array to light from said source, and optical means positioned along an optical axis of said system for effecting, selectively, an optical path relationship between individual windows of said array and said optical axis, wherein the improvement comprises:

• (a) said source of light including an array of electrically responsive light emitting elements;
• (b) a source of voltage and circuit means for connecting said emitting elements of said array, selectively, to a voltage from said source of voltage;
• (c) means for providing an optical relationship between said array of light emitting elements and said array of windows whereby each window will be exposed to light stemming from a corresponding one of the light emitting elements upon the connecting of a voltage from said source to an element;
• (d) said optical means including an acoustic wave generator and an interaction medium positioned along said optical axis, and a source of ultrasonic frequency voltages and circuit means for connecting said generator to this source of voltages for an establishing of any of a number of different acoustic wave light reflecting conditions within said interaction medium, each said optical path relationship corresponding, respectively, to each said light reflecting condition;
• (e) means for connecting a predetermined one of the elements to said source of voltage and, consequently, exposing a corresponding one of the windows to light stemming from said one element, and establishing, simultaneously, a predetermined one of said light reflecting conditions within said medium and a corresponding one of said optical path relationships between said one window and said optical axis;
• (f) means for connecting another predetermined one of the elements to said source of voltage and, consequently, exposing another and corresponding one of the windows to light stemming from said other element, and establishing, simultaneously, another predetermined one of said light reflecting conditions within said medium and a corresponding one of said optical path relationships between said other window and said optical axis.