Abstract:
One embodiment disclosed relates to an electron source for generating an electron beam. The electron source includes an electron emitter having a tip from which an electron beam is extracted. The electron further includes a non-planar extractor with an extractor opening and a built-in beam-limiting aperture. The extractor opening is larger than the beam-limiting aperture, and central axes of both the extractor opening and the beam-limiting aperture are aligned with the tip along a beam axis. Another embodiment relates to a method of generating an electron beam using an electron source having a non-planar extractor. Another embodiment relates to an array of electron sources for generating an array of electron beams. The array of electron sources includes an array of electron emitters and an array of non-planar extractor structures. Other embodiments, aspects and features are also disclosed.
Abstract:
A cathode assembly is for use in a radiation generator and includes an ohmically heated cathode, and a support having formed therein a hole and a recess at least partially surrounding the hole. In addition, there is a mount coupled to the support. The mount includes a larger outer frame positioned within the recess, a smaller inner frame carrying the ohmically heated cathode and spaced apart from the larger outer frame, and a plurality of members coupling the smaller inner frame to the larger outer frame.
Abstract:
One embodiment disclosed relates to an electron source for generating an electron beam. The electron source includes an electron emitter having a tip from which an electron beam is extracted. The electron further includes a non-planar extractor with an extractor opening and a built-in beam-limiting aperture. The extractor opening is larger than the beam-limiting aperture, and central axes of both the extractor opening and the beam-limiting aperture are aligned with the tip along a beam axis. Another embodiment relates to a method of generating an electron beam using an electron source having a non-planar extractor. Another embodiment relates to an array of electron sources for generating an array of electron beams. The array of electron sources includes an array of electron emitters and an array of non-planar extractor structures. Other embodiments, aspects and features are also disclosed.
Abstract:
An electron accelerator (10) includes a vacuum chamber (46) having an electron beam exit window (24). An electron generator (31) is positioned within the vacuum chamber for generating electrons. A housing (30) surrounds the electron generator and has a first series of openings (34) formed in the housing between the electron generator and the exit window for allowing electrons to accelerate from the electron generator out the exit window in an electron beam when a voltage potential is applied between the housing and the exit window. The housing also has a second series and third series of openings (35) formed in the housing on opposite sides of the electron generator for causing electrons to be uniformly distributed across the electron beam by flattening electrical field lines between the electron generator and the exit window.
Abstract:
The invention describes a particle source in which energy selection occurs. The energy selection occurs by sending a beam of electrically charged particles 103 eccentrically through a lens 107. As a result of this, energy dispersion will occur in an image formed by the lens. By projecting this image onto a slit 109 in an energy selecting diaphragm 108, it is possible to allow only particles in a limited portion of the energy spectrum to pass. Consequently, the passed beam 113 will have a reduced energy spread. Deflection unit 112 deflects the beam to the optical axis 101. One can also elect to deflect a beam 105 going through the middle of the lens toward the optical axis and having, for example, greater current. The energy dispersed spot is imaged on the slit by a deflector 111. When positioning the energy dispersed spot on the slit, central beam 105 is deflected from the axis to such an extent that it is stopped by the energy selecting diaphragm. Hereby reflections and contamination resulting from this beam in the region after the diaphragm are avoided. Also electron-electron interaction resulting from the electrons from the central beam interacting with the energy filtered beam in the area of deflector 112 is avoided.
Abstract:
A soft ionization device is disclosed that comprises a series of electrodes (120, 122) having spacing less than the means free path of the molecules to be ionized. In some embodiments, the soft ionization device (99) is used in various applications that require ion or electron sources such as biological or chemical reactors, ion milling, and numerous replacements for conventional hot cathode systems. In another embodiment, a valence spectrometer is disclosed that is configured to variably ionize molecules (301) by their valiancy. In other embodiments, the ionization device is coupled to a spectrometer for the characterization of biological matter. Also disclosed is a preconditioner for preparing biological matter to be ionized.
Abstract:
Für eine Kathodenstrahlröhre mit mindestens einer Gitterelektrode mit einer Blendenöffnung wird vorgeschlagen, die Gitterelektrode aus einem nichtleitendem Trägerkörper vorzugsweise einer keramischen Folie, mit einer metallisierten Fläche im Bereich der Blendenöffnung aufzubauen. Hierdurch kann die Gitterkapazität gegenüber einer metallischen Gitterelektrode verringert und die Grenzfrequenz der Strahlmodulation erhöht werden.
Abstract:
An electron gun arrangement which is particularly suitable for use in travelling wave tubes includes a substantially cylindrical ceramic body (20) which partly defines a vacuum envelope. The body (20) surrounds an electrode assembly constituted by cathode (21), grids (22,23 and 24) and an anode (25). The leads to the grids and cathode are extensive in a generally longitudinal axial direction at the end of the body (20) remote from the anode (25), electrical connection being made via pins (30-33) and metallised apertures (26-29) extensive longitudinally through the wall of the body (20). The internal diameter of the body (20) may be stepped to define ridges (38-40) to which supports for parts of the electrode assembly are fixed.