Abstract: The apparatus comprises at least one light source (3) and a plurality of test channels with in each case one optoelectronic converter (4a, 4b). In the light path between the light source and the converter is provided at least one light channel (5a, 5b) and the test material (1). The light channels are constructed as optical elements for bounding or defining a light bundle. A plurality of light channels is juxtaposed in a common casing (6a, 6b) on at least part of the light path. In each light channel can be provided a beam splitter element (12) and together form a single beam splitter (12) removably arranged in the casing. The converters (4a) can be juxtaposed on the same casing as the beam splitter (12) and each is associated with a light channel (5a). Two casings (6a, 6b) can be provided, the light source (3) in the first casing (6a) and the converters (4b) in the second casing (6b) are juxtaposed and associated with in each case one light channel (5a, 5b).

Abstract: An apparatus is provided for detecting the one-dimensional position of incidence of particle beams. The apparatus comprisesa microchannel plate having a portion that forms a strip conductor for a microstrip line, an electrode on the output surface that is formed of a plurality of stripes that extend from said strip conductor forming portion in the form of spaced comb teeth, and a ground conductor that is associated with said strip conductor;an operating power source that supplies an operating voltage to each component of said microchannel plate; andan incident position detector circuit that picks up an output signal from both ends of said strip conductor and which estimates, on the basis of the difference between the times at which said output signals were generated, the position of incidence of particle beams that encountered the surface of incidence of said microchannel plate.