Abstract: A flash radiography diode includes a cathode and an anode. The cathode includes a frustum member with a bore extending through the frustum member. The anode is a tapered anode made of an electrically conductive material and oriented toward the cathode. The anode and the cathode are housed in a chamber with a gap between the anode and the cathode. The cathode is configured to emit electrons to the tapered anode, which electrons strike the anode and create an anode plasma. The anode plasma creates X rays which propagate from the anode.

Abstract: A flash radiography diode includes a cathode and an anode. The cathode includes a frustum member with a bore extending through the frustum member. The anode is a tapered anode made of an electrically conductive material and oriented toward the cathode. The anode and the cathode are housed in a chamber with a gap between the anode and the cathode. The cathode is configured to emit electrons to the tapered anode, which electrons strike the anode and create an anode plasma. The anode plasma creates X rays which propagate from the anode.

Abstract: A medical imaging device employs a plurality of triggered plasma cathode flash X-ray sources, each of which has an axially extending round anode rod, a cathode, and a trigger electrode. The application of a trigger pulse between the electrode and the cathode produces a burst of plasma near the cathode, the plasma containing electrons that are accelerated toward and impact the anode in a region termed the "focal spot" for producing X-rays when a voltage source applies a predetermined voltage between the cathode and anode. According to the invention, a non-conducting surface interconnects the electrode with a cathode or a conductor held at the same potential as the cathode, the application of a trigger pulse to the electrode causing flashover across said surface for producing the burst of plasma.

Abstract: A medical imaging device employs a plurality of triggered plasma cathode flash X-ray sources, each of which has an axially extending round anode rod, a cathode, and a trigger electrode. The application of a trigger pulse between the electrode and the cathode produces a burst of plasma near the cathode, the plasma containing electrons that are accelerated toward and impact the anode in a region termed the "focal spot" for producing X-rays when a voltage source applies a predetermined voltage between the cathode and anode. According to the invention, a non-conducting surface interconnects the electrode with a cathode or a conductor held at the same potential as the cathode, the application of a trigger pulse to the electrode causing flashover across said surface for producing the burst of plasma.

Abstract: A plasma electron source has an apertured cathode, and a housing for defining a cavity behind the aperture. A trigger electrode, in communication with the cavity, is responsive to a short-duration trigger pulse for establishing plasma in the cavity. The plasma is sustained in the cavity subsequent to the termination of the trigger pulse by a bias circuit, which biases the cavity at a relatively low voltage with respect to the cathode for a period of time much longer than the duration of the trigger pulse.

Abstract: A plasma electron source has an apertured cathode, and a housing for defining a cavity behind the aperture. A trigger electrode, in communication with the cavity, is responsive to a short-duration trigger pulse for establishing plasma in the cavity. The plasma is sustained in the cavity subsequent to the termination of the trigger pulse by a bias circuit, which biases the cavity at a relatively low voltage with respect to the cathode for a period of time much longer than the duration of the trigger pulse.

Abstract: Radiation imaging apparatus especially suited for use in a computerized tomographic (CT) scanner employs an array of discrete X-ray sources, each being a cold cathode diode and an adjacent fixed array of closely packed radiation detectors to produce images of rapidly moving body organs such as the beating heart. A variety of alternative X-ray source embodiments are also disclosed.

Abstract: An improved diode for forming an intense electron beam and propagating the eam. The diode includes a cathode having a bore, and a rod-shaped anode having a medial tapered section which extends, approximately coaxially, through the bore of the cathode. The anode tapers at or near the cathode and is formed from electrically conductive material. The cathode is made from a material which rapidly emits electrons during the early stage of an applied voltage pulse. The electrons strike the anode and form a plasma thereon. Sufficient anode current and the formation of sufficient anode plasma affect the magnetic and electric fields to pinch the electrons closer to each other and to force the electron beam to propagate along the anode and away from the cathode and voltage supply. The tapered section of the anode increases the velocity of the pinch and the density of the electron beam.