X-ray generating mechanism using electron field emission cathode
Patent 6553096 Issued on April 22, 2003. Estimated Expiration Date: October 6, 2020. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
An x-ray generating device includes a field emission cathode formed at least partially from a nanostructure-containing material having an emitted electron current density of at least 4 A/cm2. High energy conversion efficiency and compact design are achieved due to easy focusing of cold cathode emitted electrons and dramatic reduction of heating at the anode. In addition, by pulsing the field between the cathode and the gate or anode and focusing the electron beams at different anode materials, pulsed x-ray radiation with varying energy can be generated from a single device.
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October 6, 2020. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
