This invention relates to an electron tube which stabilizes the orbits of electrons accelerated and focused by an electron lens and has a structure for effectively suppressing noise generated due to discharge. This electron tube has, at two ends of an insulating container, a cathode electrode and an anode electrode which constitute the electron lens. Particularly, in the electron tube, one end of the cathode electrode and a photocathode are supported by a conductive member arranged at one end of...

According to the invention, the conducting collector wall (23) on which the electrons are collected is surrounded by a coil winding (36) which is supplied with a periodically varying current, creating a slightly divergent axial magnetic field whose amplitude is periodically variable with time. The electron trajectories strike the collector wall at a grazing, nearly tangential angle, broadening the zone of impact, and the zone of impact is swept back and forth along the length of the collector, f...

An electron spectrometer including a high pass filter, an electron multiplier and a reflection chamber is improved by placing a planar grid in the reflection chamber between the high pass filter and the electron multiplier.

In an electron microscope, focus correction is carried out automatically, an astigmatic difference amount is displayed and astigmatism correction is executed quantitatively. Enlarged specimen images obtained by irradiating an electron beam on a specimen while changing excitation currents of an objective lens and of a stigmator coil are picked up by a capturing unit comprised of an optical lens and a capturing device and image sharpness coefficients are calculated by means of an arithmetic logic ...

In an electron tube, one end of an insulating tube is protruded toward the inside of an envelope, and an avalanche photodiode (APD) is provided on the one end of the insulating tube. Another end of the insulating tube is connected to an outer stem of the envelope. Alkali sources are provided inside the envelope. The alkali sources are disposed inside the envelope and generates alkali metal vapor to thereby form a photocathode on a predetermined part of the internal surface of the envelope. The a...

An electron gun includes a cathode portion which emits electrons, an anode portion which accelerates the emission electrons, a bias portion which is arranged between the cathode portion and the anode portion and controls trajectories of the emission electrons, a shielding portion which is arranged below the anode portion and shields some of the emission electrons, and a cooling portion which cools the shielding portion. The bias portion controls the trajectories of the electrons so as to form a ...

An electron emitter has an emitter section formed on a substrate, and a cathode electrode and an anode electrode formed on a same surface of the emitter section. A slit is formed between the cathode electrode and the anode electrode. A drive voltage from a pulse generation source is applied between the cathode electrode and the anode electrode, and the anode electrode is connected to the ground. A collector electrode is provided above the emitter section at a position facing the slit. The collec...

An electron microscope eliminates external ducting for evacuation by interlinking the interiors of a sample chamber for a sample, a casing for electron lenses and a chamber for an electron gun. Those interiors form a closed space with an evacuation path extending therethrough and are evacuated by evacuation means a vacuum pump connected to the sample chamber. The electron lenses are contained within sealed modules and the evacuation path passes between the sides of those modules and the internal...

The present invention relates to an electron detector for use in a scanning electron microscope. The detector is used to detect high and low energy backscattered electrons as well as secondary electrons. The detector is based on the use of a high transparency conductive film over the surface of the detector, whereby the surface is stable to the application of a high voltage. The detector is be used to detect both high and low energy backscattered secondary electrons and has an active surface wit...

The composition change and strained structure in a heterointerface or thin film of a multilayer thin film specimen are observed. When the composition change and strained structure are observed, comparison between a dark-field image and a bright-field image and comparison between two dark-field images are required. The position of an objective aperture disposed between the specimen and a detector is moved rapidly so that diffracted wave or transmitted wave corresponding to the dark-field image or...