Hitachi has announced a new high performance thermionic transmission electron microscope, offering high contrast and high resolution operating modes
A new thermionic transmission electron microscope (TEM), the H-7600, has been announced by Hitachi Scientific Instruments. This new TEM joins the popular H-7500 to form a family of PC-controlled TEMs, and features a Windows 2000 user interface. With an integral TV camera and autofocus system, there is no need to dim the lights when using the H-7600 so for the first time, TEM imaging becomes as easy as using a scanning electron microscope.
Bright, crisp, real time images are displayed in an image window on a flat screen monitor.
The display shows an extensive range of operating conditions such as accelerating voltage, magnification as well as a graphical display of stage position.
A micron bar, magnification, and other operating details also appear at the bottom of the image and on the micrograph.
The new autofocus system operates in less than a second using advanced image recognition technology, based on phase only correlation from the Fourier transform of images as the system moves through focus.
Images are captured digitally at a resolution of 640 x 480 pixels using the standard camera supplied.
These are saved to disk and can be printed using a video printer.
A thumbnail display gallery allows rapid retrieval of stored images.
Higher resolution images may be obtained using optional side or bottom mounted CCD cameras.
Traditional photographic methods are, of course, also available.
The H-7600 is a high performance instrument with an accelerating voltage range of 40-120kV.
It features a double-gap objective lens which can be operated in two modes: high contrast, and high resolution. For many applications, imaging a large field of view with high contrast is essential in locating the appropriate areas for high magnification work.
In addition to to the specially designed objective lens, the objective aperture is positioned exactly at the back focal plane of the objective lens, instead of below the back focal plane as is the case with many conventional TEMs.
With the objective aperture in this position, a full 160mm field of view is available on the viewing screen at a magnification of just X700, even with an objective aperture of 10µm.
This aperture position also prevents image degradation by eliminating the transmission of unwanted scattered electrons.
