Abstract: Provided are an electron gun, an electron gun component, an electron beam applicator, and an alignment method that can align the emission axis of an electron beam with the optical axis of the electron optical system of the counterpart device even when misalignment of a mounted position of the electron gun being mounted to the counterpart device is larger.

Abstract: The present invention addresses the problem of providing a method for automatically adjusting an electron beam emitted from an electron gun equipped with a photocathode to the incident axis of an electron optical system. [Solution] An incident axis alignment method for an electron gun equipped with a photocathode, the electron gun being capable of emitting an electron beam in a first state due to the photocathode being irradiated with excitation light, and the method including at least an excitation light radiation step, a first excitation light irradiation position adjustment step for changing the irradiation position of the excitation light on the photocathode and adjusting the irradiation position of the excitation light, and an electron beam center detection step for detecting whether a center line of the electron beam in the first state coincides with an incident axis of an electron optical system.

Abstract: The present invention addresses the problem of providing an electron beam generator and an electron beam applicator for which maintenance is facilitated. The electron beam generator comprises a vacuum chamber, a photocathode holder, an activation vessel, and an internal motive power transmission member. The photocathode holder is capable of moving relative to the activation vessel.

Abstract: The present invention addresses the problem of providing a device with which it is possible to adjust the focal point of an electron beam both toward a shorter focal point and toward a longer focal point after an electronic gun was fitted on a counterpart device. The aforementioned problem can be solved by an electron gun including a photocathode, and an anode, the electron gun furthermore comprising an intermediate electrode disposed between the photocathode and the anode, the intermediate electrode comprising an electron-beam passage hole through which an electron beam released from the photocathode passes, and the electron-beam passage hole having formed therein a drift space in which, when an electrical field is formed between the photocathode and the anode due to application of a voltage, the effect of the electrical field can be disregarded.

Abstract: The present invention addresses the problem of providing a sample inspection device and a sample inspection method, whereby noise is removed from a detection signal, and a generated electron beam is utilized effectively for inspection. A sample inspection device according to the present invention is provided with a light source for emitting frequency-modulated light, a photocathode for emitting an electron beam in response to receiving the frequency-modulated light, a detector for detecting electrons emitted from a sample irradiated by the electron beam and generating a detection signal, and a signal extractor for extracting a signal having a frequency corresponding to a modulation frequency of the frequency-modulated light from within the detection signal.