Methods and systems for investigating a sample using a dual beam bifocal charged particle microscope, according to the present disclosure include emitting a plurality of charged particles toward the sample, forming the plurality of charged particles into a first charged particle beam and a second charged particle beam, and modifying the focal properties of at least one of the first charged particle beam and the second charged particle beam. The focal properties of at least one of the first charged particle beam and the second charged particle beam is modified such that the corresponding focal planes of the first charged particle beam and the second charged particle beam are different.

Apparatuses and methods for comparative holographic imaging to improve structural and molecular information of reconstructions is disclosed herein. An example method at least includes acquiring a plurality of holograms of a sample, wherein each hologram of the plurality of holograms is acquired at a different electron beam energy, and determining atomic and structural information of the sample based at least on a comparison of at least two of the holograms of the plurality of holograms.

A lensless Fourier transform holography high accuracy reconstruction method using a charged particle beam apparatus which holds a sample on a diffraction surface of a diffraction grating provided on the downstream side of a traveling direction of the charged particle beam and which is formed of a material having permeability. The charged particle beam passed through the diffraction surface is image-formed, and the formed image is detected. An opening region of the diffraction grating is smaller than an irradiation region of the charged particle beam on the diffraction grating. Image data is obtained in a state where the irradiation region of the charged particle beam diffracted with the diffraction grating is within the irradiation region of the charged particle beam transmitted through the diffraction grating. Plural holograms obtained based on the image data are Fourier transformed and an intensity distribution image is displayed and stored.

An interferometric electron microscope with increased irradiating electric current density which causes electron waves to interfere with each other and includes: an electron source; an irradiating lens system a focusing lens system an observational plane an artificial grating disposed between the electron source and the irradiating lens system and diffracting the electron beam emitted from the electron source to produce a first electron wave and a second electron wave; an electron beam biprism deflecting the first electron wave and the second electron wave to pass the first electron wave through the specimen for use as an object wave and to use the second electron wave as a reference wave; and an electron beam biprism in a focusing system deflecting the objective wave and the reference wave to superimpose the objective wave and the reference wave on the observational plane to produce an image.

In an image collection system using a transmission electron microscope, a useless collection time to be spent collecting images in each of which particles overlap each other or no particle is contained, and a date volume are reduced. The image collection system includes: a control unit that moves an observation field of view in the transmission electron microscope and overlaps each other electron waves that propagate through spatially different portions within the observation field of view; a photographing unit that acquires the overlapped electron waves as an observation image; and a determination unit that determines whether a particle is present within the observation field of view.

There is provided a method of image acquisition capable of reducing the effects of diffraction contrast. This method of image acquisition is implemented in an electron microscope for generating electron microscope images with electrons transmitted through a sample. The method starts with obtaining the plural electron microscope images while causing relative variations in the direction of incidence of an electron beam with respect to the sample. An image is generated by accumulating the plural electron microscope images.

The density difference of particle beam irradiation with two optical statuses is produced utilizing a diffraction effect, within the same field of vision, such that a diffraction grating manufactured with a material which passes through a particle beam is provided on the upper side of a specimen and on the lower side of the irradiation optical system. Further, a region wider than the opening region of the diffraction grating is irradiated with the particle beam to produce the density difference of the particle beam emitted to the specimen, by superposing the particle beam, Bragg-diffracted with the opening region, and the particle beam, transmitted through the outer peripheral part of the opening region without being diffracted, with each other, and emitting the beam to the specimen.

The present invention is to generate a spatially phase modulated electron wave. A laser radiating apparatus, a spatial light phase modulator, and a photocathode are provided. The photocathode has a semiconductor film having an NEA film formed on a surface thereof, and a thickness of the semiconductor film is smaller than a value obtained by multiplying a coherent relaxation time of electrons in the semiconductor film by a moving speed of the electrons in the semiconductor film. According to the configuration, a spatial distribution of phase and a spatial distribution of intensity of spatial phase modulated light are transferred to an electron wave, and the electron wave emitted from an NEA film is modulated into the spatial distribution of phase and the spatial distribution of intensity of the light. Since the spatial distribution of phase of the light can be modulated as intended by a spatial phase modulation technique for light, it is possible to generate an electron wave having a spatial distribution of phase modulated as intended.

A device for locally manipulating a spatial phase distribution of a charged particle wave propagating along a beam axis comprises a support element having a target region for receiving the charged particle wave propagating along the beam axis and a plurality of phase adjusting elements, supported by the support element and located in the target region, for locally adjusting the phase of the charged particle wave when the charged particle wave impinges on the phase adjusting element. The device also comprises a plurality of control lines connected to the plurality of phase adjusting elements for individually controlling each phase adjusting element.

Method for acquisition of at least one hologram of a sample by off-axis holography using a transmission electron microscope, the microscope comprising an electron beam source, at least one objective lens, a sample holder, at electron biprism and means of displacing the electron beam in precession mode upstream from the sample holder and a compensator of the precession downstream from the sample holder, said method comprising the activation of means of displacing the electron beam in precession mode and the compensator and acquisition of a hologram of said sample in precession mode.