Oscillograph using a laser and heated platen

Claim 1

IN AN OSCILLOGRAPH INCLUDING MEANS FOR MOVING ALONG A SELECTED PATH A QUANTITY OF RECORD MATERIAL UPON WHICH IS TO BE RECORDED A REPRESENTATION OF THE VARIATIONS WITH TIME OF AN OSCILLOGRAPH INPUT SIGNAL, MEANS FOR EMITTING A BEAM OF RECORDING ENERGY AND FOR DIRECTING THE BEAM ALONG A PREDETERMINED PATH TO THE RECORD MATERIAL FOR INCIDENCE THEREON, MEANS OPERABLE IN RESPONSE TO THE INPUT SIGNAL FOR DEFLECTING THE BEAM LATERALLY OF THE SELECTED PATH AN AMOUNT RELATED TO THE DIFFERENCE BETWEEN THE INSTANTANEOUS VALUE OF THE SIGNAL AND A REFERENCE VALUE THEREOF, AND MEANS RECEIVING THE INPUT SIGNAL AND APPLYING IT TO THE DEFLECTING MEANS, THE IMPROVEMENT COMPRISING, IN COMBINATION, A PLATEN HAVING A SURFACE DEFINING A PORTION OF THE SELECTED PATH AND OVER WHICH THE MATERIAL MOVES, WHEREIN THE MATERIAL RESPONSE TO THE APPLICATION OF HEAT THERETO TO PROVIDE A VISIBLE RECORD OF THE AREAS THEREOF TO WHICH A PREDETERMINED AMOUNT OF THERMAL ENERGY HAS BEEN APPLIED AND WHEREIN SAID SOURCE IS A LASER AND THE RECORDING ENERGY IS THERMAL ENERGY, AND MEANS FOR HEATING THE PLATEN TO A TEMPERATURE WHICH IN COOPERATION WITH THE SPEED OF MOVEMENT OF THE MATERIAL OVER THE PLATEN SURFACE IMPRATS TO THE MATERIAL AN AMOUNT OF THERMAL ENERGY A SELECTED AMOUNT LESS THAN SAID PREDETERMINED AMOUNT, THE BEAM FROM THE LASER IMPARTING TO THE MATERIAL AN AMOUNT OF THE THERMAL ENERGY GREATER THAN SAID SELECTED AMOUNT TO PROVIDE A VISIBLE TRACE OF THE BEAM ON THE MATERIAL.