Abstract: An optical reading device comprising a housing for receiving a test plate on which, according to a fixed pattern, test substances can be provided, which reading device further comprises optical conversion elements for converting light coming from a test substance into a measuring signal which corresponds to a predetermined parameter of the test substance. The optical conversion elements comprise light-receiving areas configured in a pattern which corresponds to the pattern of the test plate. Due to the invention, it becomes possible to measure, in a non-invasive manner, an oxygen concentration in a test substance, such as a cell culture, without the oxygen content being disturbed by mechanical vibrations. As a result, in a reliable manner, measurements on substances can be performed for determining the toxicity and/or uptake or degradation rate in living cells.

Abstract: Method for component verification during operation of a placement machine having a series of feeder slots for holding component feeders with feeder markers. For verification, whether the right component has been picked up, it is necessary to determine the ID of the actual slot. The method according to the invention determines the actual slot ID from the sequence list of the placement machine.