Thick magnetic film memory device

Claim 1

A MAGNETIC MEMORY DEVICE COMPRISING: A MAGNETIC STORAGE FILM HAVING A COERCIVE FORCE ALONG A GIVEN AXIS THEREOF AND HAVING SUFFICIENT THICKNESS SO THAT ITS SELF-DEMAGNETIZING FIELD ALONG SAID AXIS IS AT LEAST EQUAL TO A LARGE PORTION OF ITS COERCIVE FORCE, SAID FIRST FILM HAVING A FIRST STABLE STATE OF EXTREME REMANENT MAGNETIZATION ALONG AND AXIS REPRESENTING A FIRST BINARY DIGIT AND A SECOND STABLE STATE OF AT LEAST PARTIAL DEMAGNETIZATION REPRESENTING A SECOND BINARY DIGIT, A MAGNETIC READ FILM ADJOINING SAID STORAGE FILM HAVING A PREFERRED EASY AXIS OF MAGNETIZATION AND TRANSVERSE THERETO A SATURABLE HARD AXIS OF MAGNETIZATION WITH NEGLIGIBLE REMANENCE, SAID SECOND FILM HAVING SUFFICIENT THICKNESS SO THAT ITS SELF-DEMAGNETIZING FIELD IS AT LEAST EQUAL TO A MAJOR PORTION OF ITS COERCIVE FORCE AND BEING ARRANGED SO THAT IT CAN BE SATURATED ALONG ITS HARD AXIS BY THE SELF-DEMAGNETIZING RETURN FLUX OF SAID FIRST FILM WHEN SAID FIRST FILM IS IN ITS FIRST STABLE STATE, SENSING MEANS INDUCTIVELY RELATED TO SAID FILMS IN SUCH A MANNER AS TO BE LINKED BY AT LEAST A PORTION OF THE RETURN FLUX EXTERNAL TO SAID FILMS, AN ELECTRICAL ENERGIZING MEANS ASSOCIATED WITH SAID FILMS INCLUDING MEANS FOR SELECTIVELY PLACING SAID FIRST FILM ALTERNATIVELY IN ITS FIRST STABLE STATE OR IN ITS SECOND STABLE STATE, SAID ENERGIZING MEANS ALSO INCLUDING NONDESTRUCTIVE READOUT MEANS FOR APPLYING MOMENTARILY TO SAID READ FILM ALONG ITS HARD AXIS A MAGNETIZING FIELD INSUFFICIENT TO CHANGE THE STABLE STATE OF SAID STORAGE FILM BUT SUFFICIENT TO VARY THE NET FLUX LINKING SAID SENSING MEANS WHEN SAID STORAGE FILM IS IN ITS SECOND STABLE STATE, THEREBY TO PRODUCE IN SAID SENSING MEANS AN OUTPUT SIGNAL INDICATIVE OF SAID SECOND BINARY DIGIT.