AN IMAGE AND SPECTRUM ACQUISITION-SYSTEM FOR A VG-HB501 STEM USING A COLOR GRAPHICS WORKSTATION

A color graphics computer workstation (VAXstation 3200) has been interfaced to a VG HB501A scanning transmission electron microscope (STEM) for image and spectrum acquisition. The system is capable of acquiring electron energy-loss (EELS) and Auger spectra in analog and pulse counting modes (both use serial recording). High-resolution images may also be acquired singly or in pairs (simultaneous bright field and annular dark field. BF/ADF or simultaneous Auger and secondary image). The system is totally isolated (optically) from the STEM and includes computer-aided focusing using image variance and histogram methods. Various measurements of the performance speed are given and the system hardware and software are described. © 1990.