Electroluminescent storage systems

Claim 1

IN COMBINATION A MATRIX-TYPE ELECTROLUMINESCENT SCREEN HAVING FIRST AND SECOND GROUPS OF ACCESS CONDUCTORS, A FIRST SOURCE OF SIGNALS AT A FIRST FREQUENCY, A SECOND SOURCE OF SIGNALS AT A SECOND FREQUENCY DISTINCT FROM SAID FIRST FREQUENCY, A FIRST LEAD, A SECOND LEAD, MEANS CONNECTED BETWEEN SAID SOURCES AND SAID LEADS TO PRODUCE ON SAID FIRST LEAD AT LEAST A PORTION OF SAID SIGNAL AT SAID FIRST FREQUENCY AND A PHASE-SHIFTED PORTION OF SAID SIGNAL AT SAID SECOND FREQUENCY AND ON SAID SECOND LEAD AT LEAST A PORTION OF SAID SIGNAL AT SAID SECOND FREQUENCY AND A PHASE-SHIFTED PORTION OF SAID SIGNAL AT SAID FIRST FREQUENCY, FIRST SELECTOR MEANS FOR APPLYING THE SIGNALS APPEARING ON SAID FIRST LEAD TO A SELECTED ONE OF SAID CONDUCTORS IN SAID FIRST GROUP, SECOND SELECTRO MEANS FOR APPLYING THE SIGNALS APPEARING ON SAID SECOND LEAD TO A SELECTED ONE OF SAID CONDUCTORS IN SAID SECOND GROUP, AN INFORMATION STORAGE SLIDE HAVING INFORMATION STORED THEREON IN THE FORM OF AREAS OF DIFFERENT OPACITY, LIGHT SENSITIVE MEANS FOR GENERATING ELECTRICAL SIGNALS IN RESPONSE TO LIGHT TRANSMITTED FROM SAID SCREEN THROUGH SAID SLIDE, AND OUTPUT CIRCUIT MEANS CONNECTED TO SAID LIGHT SENSITIVE MEANS AND RESPONSIVE TO A CROSS-MODULATION PRODUCT OF SAID FIRST AND SECOND FREQUENCIES.