LVEM5 - Technology and Design

Benchtop Design: Imaging where you need it most

Technolog and Design Lvem5

The LVEM5 has an architecture that departs from traditional models. The benchtop design alone is a significant architecture & footprint departure from classical TEM design. The LVEM5 is approximately 90% smaller than classical electron microscopes. In contrast to classical architecture, the electron optic column is very short, making up only ~ 50% of the LVEM5 tiny height. This means that the LVEM5 can be installed in a lab, on a desktop or benchtop; almost anywhere electron imaging is needed.

Low-Voltage Field Emission Gun: High brightness and high contrast

The electron source determines in large measure the parameters of the electron microscope. The uniquely-designed Schottky type field emission gun employed by the LVEM5 has very high brightness and spatial coherency.

TEM Image contrast is given by varying degree of interactions between electrons in various parts of the specimen. Low energy electrons interact much more strongly with the sample than high energy electrons of classical TEM. Electrons in the LVEM5 are strongly scattered by both inorganic and organic materials, resulting in exceptional differentiation of features. The density difference required to give 5% contrast difference at 5kV is a mere 0.074 g/cm3

Permanent magnet lenses: Cooling not required

In another industry first, the LVEM5 is designed to operate without any cooling. With conventional electron microscopes active cooling is required to remove considerable heat generated by electric current circulating in the electromagnetic lenses. Uniquely designed permanent magnet lenses used in the LVEM5 remove any need for cooling of its components.

Ion Getter Pumping: Clean vacuum, clean column, clean images

Ion pumps are inherently dry, vibration-free and achieve very high vacuum levels. They use no oil as do mechanical rotary-pumps and diffusion pumps. By making use of specially designed Ion Getter Pumps, the LVEM5 avoids all contamination in the sample space, resulting in stable imaging conditions and absence of artefacts.

Transmission Electron Microscopy: Inline, two stage optics platform

Electron optics provide the initial stages of magnification. The FEG cathode is at the base of the microscope. The electron beam is then shaped by the condenser and objective lens as electrons travel upwards through the sample. They continue towards the YAG scintillator screen for formation of the initial image. High spatial resolution on the YAG screen enables using high light-optical magnification in a unique two stage magnification system.

Light optics that are stable and reliable further magnify the initial image on the YAG screen. There is highly efficient light transport from the luminescent screen into the light optics. A selection of different light objectives allow for a wide range of magnifications.

Image capture is by means of digitial camera mounted on the top of the LVEM5. On base models, a CCD camera is used, and on TEM BOOST equipped models, a Scientific CMOS. The cameras are optimized for low-light, high dynamic range image capture. The magnified image from the light optics is captured for subsequent viewing and analysis.

Scanning Electron Microscopy: Integrated detector for multiple modes

In yet another industry first, a backscattered electron detector has been directly incorporated into an electron optics column that was originally designed for transmission electron microscopy alone, enabling scanning electron microscopy to be performed in parallel.

In SEM mode, the electron beam is focused into a narrow spot, and then scanned repeatedly over the sample. Electrons are elastically scattered at high angles back in the direction of the electron source. These back-scattered electrons are collected by an annular solid-state detector – separately for each scanned point. The spatial intensity distribution of the backscattered electrons is used to form the final image in the PC software.

The combination of selected spot sizes and optimized working distances allow for a wide range of magnifications. The small working distance creates high spatial resolution and a segmented semi-annular detector provides the choices of material of relief contrast.

Ingenious design: We worked hard, so you don’t have to

The operating console allows a great degrees of comfort as the operator is free to operate the system and observe results via the monitor, away from the microscope body. Feedback is provided directly on the control panel as well as through the LVEM5’s comprehensive software.

The LVEM5 is so remarkably simple that anyone can use it. All in all, the LVEM5 marks a radical and refreshing departure from the classical electron microscope architecture, a departure that is welcomed by the ambitious researcher.





LVEM25 - Technology and Design

Field Emission Gun:

Technolog and Design Lvem5

The uniquely-designed 25kV Schottky type FEG (field emission gun) employed by the LVEM25 has very high brightness and spatial coherence with a lifetime of several thousand hours. The high brightness and small virtual source of the electron gun allows transmission and scanning modes in a single instrument.

Ion Getter pumping: clean vacuum, clean column, clean images

Ion pumps are inherently dry, vibration-free and achieve very high vacuum levels. By making use of specially designed ion getter pumps, the LVEM25 avoids all contamination in the sample space, resulting in stable imaging conditions and the absence of any artifacts.

Permanent magnet lenses:

The LVEM25 is designed to operate without any cooling. With conventional electron microscopes active cooling is required to remove considerable heat generated by electric current circulating in the electromagnetic lenses. The uniquely designed permanent magnet lenses used in the LVEM25 require no cooling.

Transmission Electron Microscopy: inline, two stage optics platform

Electron optics provide the initial stages of magnification cation where the initial image is formed on a YAG scintillator screen.

Light optics that are stable and reliable, further magnify the initial image from the YAG screen. Light transport from the fluorescent screen into the light optics is highly efficient.

Digital Imaging is done by means of a TE Cooled Scientific CMOS camera with 2560×2160 pixels mounted on the top of the LVEM25. The image capture software is designed for acquisition, documentation, and analysis of high performance image data. Various image processing procedures, such as summing, live FFT and automatic contrast adjustment are available.