Fluidic connectors, methods, and devices for performing analyses in microfluidic systems are provided. The waveform has a substantially vertical rising portion 831) forming an instantaneous, of time 10 secs or so between T0 and T1, transition between currents I1 and I1 which are at a current value less than peak currents IP. The sealing element is formed by a resilient hollow section body which has at right angles to its longitudinal extent a part-zone which is curved in an arc shape in an open position of the two apparatus parts and rests resiliently on the mating surface in the closed position of the two apparatus parts. By incorporating the basic objective lens and the compound lens, different resolutions such as 1200 dpi, 1600 dpi and 2400 dpi of the optical scanner are obtained without redesigning the lens device, the current specification of the optical scanner is also varied. The image region is printed using the system control parameters associated with the selected similar reference image region. Consequently, component parts which have undercut surfaces in the illumination direction can be measured in a single measuring operation.