Apparatus for producing X-rays for use in imaging

摘要

An apparatus for producing x-rays for use in imaging applications having a piezoelectric or pyroelectric crystal with an upper surface and a conducting film coating the upper surface. The crystal includes a plurality of field emitters formed as micrometer-scale exposed regions in the crystal having a one or more sharp peaks or ridges, or parallel trenches forming a wedge shaped emitter. The crystal is alternately heated and cooled over a period of time so that spontaneous charge polarization occurs in the crystal. The spontaneous charge polarization causes a perpendicular electric field to arise on the crystal's top and bottom faces, that is enhanced by the sharp peaks or ridges, thereby causing field emission of surface electrons from that location. X-rays are produced when the emitted electrons strike a target material located adjacent to the emitting face, and the X-rays may be filtered or collimated.

主权项

1. An apparatus, comprising:
a pyroelectric crystal having an upper surface; a conducting film coating the upper surface of the crystal; said crystal including a plurality of electron field emitters, the electron field emitters comprising a micrometer-scale exposed region on the crystal, the exposed region having one or more sharp peaks or ridges; a second conducting film coating the conducting film and the micrometer-scale exposed regions of the crystal; and a heater/cooler adjacent to the crystal; wherein said crystal and said electron field emitters are maintained in a low pressure environment.