Abstract The device consists of a wafer of polycrystalline perovskite oxide ceramic such as barium titanate, lead titanate - lead zirconate, or lead titanate-lead zirconate with 7.5% or less of the lead substituted for by lanthanum. Electrical terminals are joined to the wafer edges. When the ceramic is exposed to visible radiation such as sunlight a high voltage appears across the terminals and an electrical current flows through a load resistance connected between said terminals. The voltage across the load resistance depends upon the length of the wafer between the two terminals and the magnitude of the load resistance. Voltages of at least 500 volts per inch are produced for high values of load resistance. When the load resistance is high the magnitude of the voltage is independent of the intensity of the light over a large range. When the load resistance is low the current is directly proportional to the intensity of the light over many orders of magnitude. In preparing the ceramic as a ferroelectric cement it is subjected to poling whereby high voltage is placed across the electrode of the element for a short period of time.
A METHOD FOR PRODUCING CURRENT IN DIRECT PROPORTION TO INTENSITY OF LIGHT COMPRISING APPLYING AN ELECTRIC VOLTAGE OF PREDETERMINED MAGNITUDE TO A POLYCRYSTALLINE FERROELECTRIC CERAMIC FOR A PREDETERMINED TIME TO POLE THE POLYCRYSTALLINE FERROELECTRIC CERAMIC, REMOVING THE APPLIED VOLTAGE, DISPOSING TWO ELECTRODE IN CONDUCTIVE CONTACT WITH THE POLYCRYSTALLINE FERROELECTRIC CERMIC, ATTACHING AN ELECTRICAL LEAD TO EACH ELECTRODE, CONNECTING A LOW RESISTANCE BETWEEN THE TWO LEADS, IMPINGING LIGHT HAVING A CERTAIN INTENSITY UPON THE POLYCRYSTALLINE FERROELECTRIC CERMIC, AND PRODUCING CURRENT THROUGH THE RESISTANCE WHICH IS IN DIRECT PROPORTION TO THE INTENSITY OF THE LIGHT IMPINGED UPON THE POLYCRYSTALLINE FERROELECTRIC CERAMIC.
Claim 2
Independent Claim
99 words
A METHOD FOR PRODUCING CURRENT IN DIRECT PROPORTION TO INTENSITY OF LIGHT COMPRISING APPLYING AN ELECTRIC VOLTAGE OF PREDETERMINED MAGNITUDE TO A POLYCRYSTALLINE FERROELECTRIC CERAMIC FOR A PREDETERMINED TIME TO POLE THE POLYCRYSTALLINE FERROELECTRIC CERAMIC, REMOVING THE APPLIED VOLTAGE, DISPOSING TWO ELECTRODE IN CONDUCTIVE CONTACT WITH THE POLYCRYSTALLINE FERROELECTRIC CERMIC, ATTACHING AN ELECTRICAL LEAD TO EACH ELECTRODE, CONNECTING A LOW RESISTANCE BETWEEN THE TWO LEADS, IMPINGING LIGHT HAVING A CERTAIN INTENSITY UPON THE POLYCRYSTALLINE FERROELECTRIC CERMIC, AND PRODUCING CURRENT THROUGH THE RESISTANCE WHICH IS IN DIRECT PROPORTION TO THE INTENSITY OF THE LIGHT IMPINGED UPON THE POLYCRYSTALLINE FERROELECTRIC CERAMIC.
Claim 3
Independent Claim
104 words
A method for producing a constant high voltage by impinging light of varying intensities upon a polycrystalline ferroelectric ceramic comprising applying an electric voltage of predetermined magnitude to a polycrystalline ferroelectric ceramic for a predetermined time to pole the polycrystalline ferroelectric ceramic, removing the applied voltage, disposing two electrodes in conductive contact with the polycrystalline ferroelectric ceramic, attaching an electrical lead to each electrode, connecting a high resistance between the two leads, impinging light of varying intensities upon the polycrystalline ferroelectric ceramic, producing a constant high voltage across the resistance irrespective of the varying intensities of the light impinged upon the polycrystalline ferroelectric ceramic.
Claim 4
Independent Claim
104 words
A method for producing a constant high voltage by impinging light of varying intensities upon a polycrystalline ferroelectric ceramic comprising applying an electric voltage of predetermined magnitude to a polycrystalline ferroelectric ceramic for a predetermined time to pole the polycrystalline ferroelectric ceramic, removing the applied voltage, disposing two electrodes in conductive contact with the polycrystalline ferroelectric ceramic, attaching an electrical lead to each electrode, connecting a high resistance between the two leads, impinging light of varying intensities upon the polycrystalline ferroelectric ceramic, producing a constant high voltage across the resistance irrespective of the varying intensities of the light impinged upon the polycrystalline ferroelectric ceramic.