Electron beam applicator, and electron beam emission method in electron beam applicator
AssigneePhoto electron Soul Inc.
InventorTomohiro Nishitani
Life of this patent
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Abstract
An object is to provide an electron beam applicator suitable for an electron gun having a photocathode and an electron beam emission method in the electron beam applicator. The object can be achieved by an electron beam applicator including: an electron gun section; a main body section; and a control unit. The electron gun section includes a light source, a photocathode that emits an electron beam in response to receiving excitation light emitted from the light source, and an anode. The main body section includes an objective lens that converges an electron beam emitted from the electron gun section. The control unit controls at least convergence power of the objective lens in accordance with a size of an electron beam emitted from the photocathode.
Claims20
An electron beam applicator comprising:
- an electron gun section;
- a main body section;
- and
- a control unit,
- wherein the electron gun section includes
- a light source,
- a photocathode that emits an electron beam in response to receiving excitation light emitted from the light source, wherein the photocathode excludes a round tip for emitting electrons, and
- an anode,
- wherein the main body section includes
- an objective lens that converges an electron beam emitted from the electron gun section, in absence of a condenser lens and an aperture, and
- wherein the control unit controls at least convergence power of the objective lens in accordance with a size of an electron beam emitted from the photocathode.
An electron beam emission method in an electron beam applicator,
- wherein the electron beam applicator includes an electron gun section, a main body section, and a control unit,
- wherein the electron gun section includes
- a light source,
- a photocathode that emits an electron beam in response to receiving excitation light emitted from the light source, wherein the photocathode excludes a round tip for emitting electrons, and
- an anode,
- wherein the main body section includes
- an objective lens that converges an electron beam emitted from the electron gun section, in absence of a condenser lens and an aperture;
- the emission method comprising:
- an electron beam emission step of emitting an electron beam from the photocathode in response to receiving excitation light emitted from a light source;
- an electron beam traveling step of causing an electron beam emitted by the electron beam emission step to travel toward the objective lens arranged in the main body section;
- and
- an electron beam convergence step of converging the electron beam, which reached the main body section by the electron beam traveling step, by using the objective lens, in the absence of the condenser lens and the aperture, and
- wherein in the electron beam traveling step, the electron beam emitted from the photocathode travels without having a focal point until reaching the objective lens,
- wherein in the electron beam convergence step, the control unit controls convergence power of the objective lens for controlling a degree of convergence of the electron beam.
An electron beam emission method in an electron beam applicator,
- wherein the electron beam applicator includes an electron gun section, a main body section, and a control unit,
- wherein the electron gun section includes
- a light source,
- a photocathode that emits an electron beam in response to receiving excitation light emitted from the light source, wherein the photocathode excludes a round tip for emitting electrons,
- an anode, and
- an intermediate electrode that is arranged between the photocathode and the anode,
- wherein the main body section includes
- an objective lens that converges an electron beam emitted from the electron gun section, in absence of a condenser lens and an aperture;
- the emission method comprising:
- an electron beam emission step of emitting an electron beam from the photocathode in response to receiving excitation light emitted from a light source;
- an electron beam traveling step of causing an electron beam emitted by the electron beam emission step to travel toward the objective lens arranged in the main body section;
- and
- an electron beam convergence step of converging the electron beam, which reached the main body section by the electron beam traveling step, by using the objective lens, in the absence of the condenser lens and the aperture,
- wherein in the electron beam traveling step, the control unit controls the intermediate electrode so that the electron beam emitted from the photocathode
- travels so as to have no focal point between the photocathode and the objective lens, or
- travels so as to have a focal point between the photocathode and the objective lens,
- wherein in the electron beam convergence step, the control unit controls convergence power of the objective lens for controlling a degree of convergence of the electron beam.
Dependencies are inferred from the claim text.