Photo-magnetic memory devices

Claim 1

APPARATUS FOR SENSING THE REMANENT MAGNETIC STATE OF A PREDETERMINED MAGNETIC ELEMENT SELECTED FROM A FIRST PLURALITY OF MAGNETIC ELEMENTS, EACH ELEMENT HAVING AT LEAST TWO STABLE STATES OF MAGNETIZATION ALONG A CERTAIN AXIS OF MAGNETIZATION AND EXISTING IN ONE OR THE OTHER OF SAID STABLE STATES COMPRISING A SOURCE OF LIGHT WAVES HAVING VIBRATIONS CONFINED SUBSTANTIALLY TO ONE PLANE, MEANS FOR DIVIDING SAID LIGHT WAVES INTO PARALLEL LIGHT BEAMS, ONE FOR EACH MAGNETIC ELEMENT IN SAID FIRST PLURALITY OF MAGNETIC ELEMENTS, A SECOND PLURALITY OF MAGNETIC ELEMENTS POSITIONED IN OPTICAL ALIGNMENT WITH SAID FIRST PLURALITY OF MAGNETIC ELEMENTS, EACH MAGNETIC ELEMENT HAVING AT LEAST TWO STABLE STATES OF MAGNETIZATION, AND ALL BUT ONE MAGNETIC ELEMENT EXISTING IN THE SAME STABLE STATE, SAID ONE MAGNETIC ELEMENT BEING IN OPTICAL ALIGNMENT WITH SAID PREDETERMINED MAGNETIC ELEMENT AND EXISTING IN A DIFFERENT MAGNETIC STATE FROM THE OTHER MAGNETIC ELEMENTS IN SAID FIRST PLURALITY, SAID SECOND PLURALITY BEING POSITIONED TO RECEIVE SAID PARALLEL BEAMS OF LIGHT WAVES AT AN ANGLE OTHER THAN NORMAL THERETO AND AT AN ANGLE OTHER THAN 90* WITH SAID AXIS OF MAGNETIZATION, THE LIGHT BEAMS INCIDENT TO THE MAGNETIC ELEMENTS EXISTING IN THE SAME MAGNETIC STATE UNDERGOING ROTATION TO THE EXTENT OF A PREDETERMINED ANGULAR DISTANCE IN A FIRST PREDETERMINED DIRECTION DUE TO SAID SAME MAGNETIC STATE, THE LIGHT BEAM INCIDENT TO SAID ONE MAGNETIC ELEMENT UNDERGOING ROTATION TO THE EXTENT OF A PREDETERMINED ANGULAR DISTANCE IN A SECOND PREDETERMINED DIRECTION DUE TO SAID DIFFERENT STATE OF MAGNETIZATION, A FIRST ANALYZING MEANS FOR TRANSMITTING THE LIGHT BEAM WHICH HAS BEEN ROTATED IN SAID SECOND PREDETERMINED DIRECTION AND FOR BLOCKING THE LIGHT BEAMS WHICH HAVE BEEN ROTATED IN SAID FIRST DIRECTION, SAID TRANSMITTED LIGHT BEAM BEING INCIDENT ON SAID PREDETERMINED MAGNETIC ELEMENT AT AN ANGLE OTHER THAN NORMAL THERETO AND AT AN ANGLE OTHER THAN 90* WITH SAID AXIS OF MAGNETIZATION, SAID LIGHT BEAM FURTHER UNDERGOING ROTATION BY THE EXISTING STATE OF MAGNETIZATION OF SAID PREDETERMINED MAGNETIC ELEMENT, AND A SECOND ANALYZING MEANS FOR RECEIVING SAID FURTHER ROTATED LIGHT WAVES FOR DETERMINING THE EXTENT OF ROTATION THEREOF AND THEREBY INDICATING THE REMANENT STATE OF SAID PREDETERMINED MAGNETIC ELEMENT.