A photoinjector system containing modularly-structured waveguide-mode launcher, which is reversibly connected to the RF gun (containing a tubular construction formed with disattachably-affixed to one another structurally-complementary halves); and a solenoid magnet in operation enclosing such tubular structure in a central hollow. The resulting quality, power, and frequency rate of operation as well as cost of manufacturing and operation of the system are superior as compared with those of a related art system.

A photoinjector system containing modularly-structured waveguide-mode launcher, which is reversibly connected to the RF gun (containing a tubular construction formed with disattachably-affixed to one another structurally-complementary halves); and a solenoid magnet in operation enclosing such tubular structure in a central hollow. The resulting quality, power, and frequency rate of operation as well as cost of manufacturing and operation of the system are superior as compared with those of a related art system.

A cathode mechanism of an electron gun includes a crystal to emit a thermal electron from an end surface by being heated, a holding part to hold the crystal in a state where the end surface is exposed and at least a part of other surfaces of the crystal is covered, a first supporting post and a second supporting post each to support the holding part and extend while maintaining an unchanged sectional size, a first base part to fix the first supporting post, and a second base part to fix the second supporting post, wherein the holding part, the first supporting post, the second supporting post, the first base part, and the second base part are formed in an integrated structure made of the same material, and the crystal is heated by supplying a current to the integrated structure.

A cathode mechanism of an electron gun includes a crystal to emit a thermal electron from an end surface by being heated, a holding part to hold the crystal in a state where the end surface is exposed and at least a part of other surfaces of the crystal is covered, a first supporting post and a second supporting post each to support the holding part and extend while maintaining an unchanged sectional size, a first base part to fix the first supporting post, and a second base part to fix the second supporting post, wherein the holding part, the first supporting post, the second supporting post, the first base part, and the second base part are formed in an integrated structure made of the same material, and the crystal is heated by supplying a current to the integrated structure.

A photoinjector system containing modularly-structured waveguide-mode launcher, which is reversibly connected to the RF gun (containing a tubular construction formed with disattachably-affixed to one another structurally-complementary halves); and a solenoid magnet in operation enclosing such tubular structure in a central hollow. The resulting quality, power, and frequency rate of operation as well as cost of manufacturing and operation of the system are superior as compared with those of a related art system.

An electron gun and an apparatus incorporating the electron gun. The electron gun includes an electron emission element, an electrode, a control element, and a control circuit. The electron emission element is arranged to be activated to emit electron beam. The electrode is arranged to be electrically connected with a power supply to accelerate the emitted electron beam. The control element may be arranged between the electron emission element and the electrode. The control element is arranged to be electrically connected with the power supply to provide an electric field to control emission of electron beams from the electron emission element. The control circuit is electrically connected with the control element for changing the electric field provided by the control element.

Novel and advantageous systems and methods for performing X-ray imaging by using an X-ray source with source grating functionality incorporated therein are provided. An electron beam can be electromagnetically manipulated such that the X-ray source emits radiation in a pattern that is the same as if the radiation had already passed through a source grating.

A photoinjector system containing modularly-structured waveguide-mode launcher, which is reversibly connected to the RF gun (containing a tubular construction formed with disattachably-affixed to one another structurally-complementary halves); and a solenoid magnet in operation enclosing such tubular structure in a central hollow. The resulting quality, power, and frequency rate of operation as well as cost of manufacturing and operation of the system are superior as compared with those of a related art system.

To suppress both influence of electron emission from a cathode side surface and consumption of energy to be supplied to a heater, while being provided with a grid, an electron gun of the present invention includes: a cathode capable of emitting electrons by heating; a grid capable of controlling the electron emission; and a cathode shield which is an conductor including a material portion located in the vicinity of a side surface of the cathode and facing at least a portion of the side surface via a gap or a heat insulating material, and not being made in direct physical coupling nor in direct physical contact with the cathode.

To suppress both influence of electron emission from a cathode side surface and consumption of energy to be supplied to a heater, while being provided with a grid, an electron gun of the present invention includes: a cathode capable of emitting electrons by heating; a grid capable of controlling the electron emission; and a cathode shield which is an conductor including a material portion located in the vicinity of a side surface of the cathode and facing at least a portion of the side surface via a gap or a heat insulating material, and not being made in direct physical coupling nor in direct physical contact with the cathode.