Delong TEM Transmission Electron Microscopes

Delong TEM Transmission Electron Microscopes

Imaging with a transmission electron microscope (TEM) involves the penetration of the electron beam through thin sample sections. It is in this mode that the enhanced native contrast advantages of the LVEM5 and LVEM25 are most pronounced. In transmission electron microscopy a high-magnification image is obtained as the electrons of the incident beam travels through, and are differentially scattered by the atoms comprising a tiny area of the sample, then guided through electron-optical path and converted to light-optical image by appropriate detector (scintillator and camera). Typical samples for TEM analysis are ultra-thin sections of bulk materials, nano-sized particles, or filaments deposited onto a thin film.

Due to ultra-high contrast, and image generation brought by a bright and highly coherent electron beam, notable improvements are observed in the quality of the TEM results. In particular, samples that would normally need to be prepared with contrast improving stains would be able to forgo this step for imaging on the LVEM5. The LVEM microscopes are the only transmission electron microscopes available in a benchtop configuration. The LVEM25's miniature size means that it can be installed in your workspace, right where you need it. The LVEM25 does not require a dedicated facility for installation. No special power or cooling requirements are needed and vibration isolation is generally not a concern.

Benefits of improved contrast

Comparison of LVEM5 & LVEM25

 

  • LVEM5
  • LVEM25

Delong LVEM5

Benchtop Design: Imaging Where You Need it Most

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's 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. Low energy electrons interact much more strongly with a sample than the high energy electrons of a classical TEM. Electrons in the LVEM5 are strongly scattered by both inorganic and organic materials, resulting in exceptional differentiation of features.

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 digital 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.

LVEM5 Brochure

Delong LVEM25

Field Emission Gun: High Brightness and High Contrast

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.

Permanent Magnet Lenses: Cooling not Required

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. 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 LVEM25 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.
  • 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.

LVEM25 Brochure