Electroluminescent device

Claim 1

IN COMBINATION, A FIRST ARRAY OF PARALLEL, SEPARTED ELECTRICAL CONDUCTORS EXTENDING ALONG A FIRST DIRECTION, A SECOND ARRAY OF PARALLEL, SEPARATED ELECTRICAL CONDUCTORS EXTENDING ALONG A SECOND AND DIFFERENT DIRECTION, A STRUCTURE INTERPOSED BETWEEN AND IN ELECTRICAL CONTACT WITH SAID FIRST AND SECOND ARRAYS, SAID STRUCTURE INCLUDING IN SERIES CONNECTION A FIRST HOMOGENEOUS ELECTROLUMINESCENT ELEMENT AND A SECOND PHOTOCONDUCTIVE ELEMENT, SAID FIRST ELEMENT HAVING A WAVELENGTH-DEPENDENT LIGHT EMISSION CHARACTERISTIC AT WHICH THE EMISSION ATTAINS A MAXIMUM VALUE FOR A GIVEN RANGE OF WAVE LENGTHS, SAID SECAND ELEMENT HAVING A WAVELENGTH-DEPENDENT PHOTOCONDUCTIVE SENSITIVITY CHARACTERISTIC AT WHICH THE SENSITIVITY ATTAINS A MAXIMUM VALUE OVER SUBSTANTIALLY THE SAME SAID RANGE AND FURTHER HAVING A FUNDAMENTAL ABSORPTION EDGE DEFINED BY A WAVELENGTH SMALLER THAN ANY WAVELENGTH IN SAID RANGE, A TRANSPARENT INSULATING FILM APPLIED OVER SAID FIRST ARRAY, AND AN ELECTROLUMINESCENT CELL APPLIED OVER SAID INSULATING FILM, SAID CELL INCLUDING A THIRD HETEROGENEOUS ELECTROLUMINESCENT LAYER ELECTRICALLY CON NECTED TO AND INTERPOSED BETWEEN FIRST AND SECOND ELECTRICALLY CONDUCTIVE FILMS.