Cambridge University Engineering Department
Scientific Imaging Group
The Virtual SEM
VSEM : an interactive simulation and virtual reality model of the scanning electron microscope
The capabilities of the scanning electron microscope (SEM) continue to expand. Improvements in electron optics, support circuitry and in the ability of the instrument to accommodate a wide range of specimens mean that the modern SEM competes with both optical and transmission electron microscopes. Beyond this, the application of image processing and other software techniques has led to much more meaningful displays and enhanced facilities for quantitative work. The transformation of the SEM over the last decade into a fully software-driven instrument has added new versatility. However, effective use of the SEM has always called for considerable experience and understanding of its operation; the improvements referred to have not alleviated this difficulty, and have actually emphasised the essential need for an operator to receive specialist training to gain the requisite skills. In common with other advanced forms of microscopy, SEM operating costs and other commercial pressures strictly limit the time available for staff training. Moreover, training has traditionally called for the presence of an experienced operator to supervise the novice and safeguard the instrument from inadvertent damage. This situation is compounded by the restricted accessibility of most SEMs, making it impracticable to train more than one or two operators at a time in the normal SEM environment.
It was with these difficulties in mind that a solution was developed in Cambridge University Engineering Department aimed at improving training opportunities for prospective SE microscopists. It makes use of a Virtual SEM, that is, a software simulation of the scanning electron microscope which emulates both the behaviour and the user interface of the instrument, and provides a general introduction to modern scanning electron microscopy.