Display System for Use with a Scanning Electron Energy Analyzing Microscope

The display system consists of two scintillators, photomultipliers, and direct-view storage tubes; an optical superposition device with color filters; a conventional cathode-ray oscilloscope; and the associated circuitry, containing voltage supplies, amplifiers, etc. (See Fig. 6) The virtues of the system are well illustrated in use at low scattered electron intensities, whether low count rate be due to low beam strength, small beam-defining slit settings, or high energy resolution. The presentation magnification may be chosen by simple switching. Centering on the region of interest in the specimen is obtained by adjusting the dc bias voltages applied to the microscope deflection plates. Successive scans may then be piled up until visual observation indicates that a good statistical integration has been achieved for the particularly interesting region of the specimen. The recording camera may be interposed leisurely, and so may the color position device if desired, while the displays are retained in storage. The presented intensity may be adjusted for photographic ease, and additional photographs may be taken much later. Meanwhile, if the specimen contains sharp contrast edges in both directions of the microscope beam deflection plates, objective measurements may be made of the available resolution by observing signal rise time on the ordinary oscilloscope. The adjustability, versatility and convenience in using this display system have been well established with an experimental scanning microscope providing two energy-separated beams of electrons from those leaving the specimen. The general system complexity is a major disadvantage.