Abstract: A system may include a controller couplable to an imaging sub-system utilizing multiple particle beams, where the imaging sub-system includes one or more control elements to manipulate the two or more particle beams that are adjustable with two or more control parameters. The controller may select values of the two or more control parameters by iteratively performing steps until one or more termination conditions are met. For example, the controller may receive measurements of changes of distortions of the particle beams resulting from individual adjustments of the control parameters. The controller may further calculate values of the control parameters that reduce the distortions of the particle beams based on the changes of the distortions resulting from the individual adjustments. The controller may further direct the adjustment of the values of the control parameters to the calculated values.

Abstract: A multi-electron beam system that forms hundreds of beamlets can focus the beamlets, reduce Coulomb interaction effects, and improve resolutions of the beamlets. A Wien filter with electrostatic and magnetic deflection fields can separate the secondary electron beams from the 5 primary electron beams and can correct the astigmatism and source energy dispersion blurs for all the beamlets simultaneously.

Abstract: An aperture array for a multi-beam array system and a method of selecting a subset of a beam from a multi-beam array system are provided. The aperture array comprises an array body arranged proximate to a beam source. The array body comprises a plurality of apertures, at least two of the apertures having different geometries. The array body is movable, via an actuator, relative to an optical axis of the beam source, such that a subset of a beam from the beam source is selected based on the geometry of the aperture that is intersected by the optical axis.

Abstract: A multi-beam system includes a light source configured to emit light; a fiber bundle connected to the light source; and a camera configured to capture an image set including images corresponding to each fiber connected to the light source. The fiber bundle includes a central fiber having one end connected to the light source, and N layers of fibers surrounding the central fiber. The first layer of fibers includes M fibers, each having one end connected to the light source, and the Nth layer of fibers includes more than M fibers, but only M fibers in the Nth layer of fibers have one end connected the light source. A processor is configured to determine a centroid of each image in the image set to produce a centroid map and generate a fiber location map comprising fiber locations of all fibers in the fiber bundle based on the centroid map.

Abstract: An aperture array for a multi-beam array system and a method of selecting a subset of a beam from a multi-beam array system are provided. The aperture array comprises an array body arranged proximate to a beam source. The array body comprises a plurality of apertures, at least two of the apertures having different geometries. The array body is movable, via an actuator, relative to an optical axis of the beam source, such that a subset of a beam from the beam source is selected based on the geometry of the aperture that is intersected by the optical axis.

Abstract: These electron beam separator designs address thermally-induced beam drift in an electron-optical system. A heater coil wrapped around the beam separator unit can maintain constant power. Additional coils also can be wrapped around the beam separator in a bifilar manner, which can maintain constant power in the beam separator coils. Wien power can be determined, and then heater coil current can be determined.

Abstract: These electron beam separator designs address thermally-induced beam drift in an electron-optical system. A heater coil wrapped around the beam separator unit can maintain constant power. Additional coils also can be wrapped around the beam separator in a bifilar manner, which can maintain constant power in the beam separator coils. Wien power can be determined, and then heater coil current can be determined.

Abstract: A scanning electron microscopy system is disclosed. The system includes an electron beam source configured to generate a primary electron beam. The system includes a sample stage configured to secure a sample. The system includes a set of electron-optical elements configured to direct at least a portion of the primary electron beam onto a portion of the sample. The set of electron-optical elements includes an upper deflector assembly and a lower deflector assembly. The upper deflector assembly is configured to compensate for chromatic aberration in the primary electron beam caused by the lower deflector assembly. In addition, the system includes a detector assembly configured to detect electrons emanating from the surface of the sample.

Abstract: A holographic polymer dispersed liquid crystal (HPDLC) tunable filter exhibits switching times of no more than 20 microseconds. The HPDLC tunable filter can be utilized in a variety of applications. An HPDLC tunable filter stack can be utilized in a hyperspectral imaging system capable of spectrally multiplexing hyperspectral imaging data acquired while the hyperspectral imaging system is airborne. HPDLC tunable filter stacks can be utilized in high speed switchable optical shielding systems, for example as a coating for a visor or an aircraft canopy. These HPDLC tunable filter stacks can be fabricated using a spin coating apparatus and associated fabrication methods.

Abstract: A system for measuring cathodoluminescence from a substrate includes an electron beam source configured to generate an electron beam, a sample stage configured to secure a sample and an electron-optical column including a set of electron-optical elements to direct at least a portion of the electron beam through onto a portion of the sample. The system also includes a set of guide optics located at a position within or below the electron-optical column and a set of collection optics, wherein the set of guide optics captures cathodoluminescent light emitted from the sample in response to the electron beam and directs the cathodoluminescent light to the set of collection optics. In addition, the system includes a detector. The set of collection optics is configured to image the cathodoluminescent light onto the detector.

Abstract: A holographic polymer dispersed liquid crystal (HPDLC) tunable filter exhibits switching times of no more than 20 microseconds. The HPDLC tunable filter can be utilized in a variety of applications. An HPDLC tunable filter stack can be utilized in a hyperspectral imaging system capable of spectrally multiplexing hyperspectral imaging data acquired while the hyperspectral imaging system is airborne. HPDLC tunable filter stacks can be utilized in high speed switchable optical shielding systems, for example as a coating for a visor or an aircraft canopy. These HPDLC tunable filter stacks can be fabricated using a spin coating apparatus and associated fabrication methods.

Abstract: A holographic polymer dispersed liquid crystal (HPDLC) tunable filter exhibits switching times of no more than 20 microseconds. The HPDLC tunable filter can be utilized in a variety of applications. An HPDLC tunable filter stack can be utilized in a hyperspectral imaging system capable of spectrally multiplexing hyperspectral imaging data acquired while the hyperspectral imaging system is airborne. HPDLC tunable filter stacks can be utilized in high speed switchable optical shielding systems, for example as a coating for a visor or an aircraft canopy. These HPDLC tunable filter stacks can be fabricated using a spin coating apparatus and associated fabrication methods.

Abstract: A scanning electron microscopy system is disclosed. The system includes an electron beam source configured to generate a primary electron beam. The system includes a sample stage configured to secure a sample. The system includes a set of electron-optical elements configured to direct at least a portion of the primary electron beam onto a portion of the sample. The set of electron-optical elements includes an upper deflector assembly and a lower deflector assembly. The upper deflect assembly is configured to compensate for chromatic aberration in the primary electron beam caused by the lower deflector assembly. In addition, the system includes a detector assembly positioned configured to detect electrons emanating from the surface of the sample.

Abstract: A holographic polymer dispersed liquid crystal (HPDLC) tunable filter exhibits switching times of no more than 20 microseconds. The HPDLC tunable filter can be utilized in a variety of applications. An HPDLC tunable filter stack can be utilized in a hyperspectral imaging system capable of spectrally multiplexing hyperspectral imaging data acquired while the hyperspectral imaging system is airborne. HPDLC tunable filter stacks can be utilized in high speed switchable optical shielding systems, for example as a coating for a visor or an aircraft canopy. These HPDLC tunable filter stacks can be fabricated using a spin coating apparatus and associated fabrication methods.