Abstract: First and second image frames are produced using respectively different sets of pixels. The different sets of pixels arise from movement of an image digitiser (13) with respect to an image (10). The image frames are recorded on a film (32) using an output display device (30). The frames are recorded with such relative positions that the film can be displayed so that the frames are viewed with such a superimposition that the position of the pixels in the first and second sets relative to viewed image are substantially the same on the respective positions of those pixels relative to the image to be reproduced. In this way, the resolution of a recorded image can be greater than that of the output device.

Abstract: A method of performing Auger electron spectroscopic surface analysis, e.g. of silicon, in which the secondary electrons which leave the target material are analyzed without the use of an electron optic device. An a.c. signal modulated retard potential is applied in ramp form to the target and a detection circuit connected to the target measures the component of current to earth from the target at the second harmonic of the a.c. modulation signal. The output of the detection circuit is plotted as a function of the retard potential to produce a spectrum of the first derivative of the secondary electron energy with respect to the retard potential so as to enhance the display of Auger transitions. Alternative realizations are described of a circuit arrangement including a four-port network for coupling the target, a.c. modulation signal source, retard potential source, and detector circuit.