ABSTRACT
This chapter presents a discussion of the classification of measuring structures. In the first instance, measuring instruments can be divided into four classes with respect to their functional structure, the type of signal structure information, their spatial structure or architecture and automated structures. The functional structure describes the way the measurement is performed and depends on the number of unknown related physical quantities to be measured and whether there is an active or passive quantity involved. Measurement systems can be distinguished related to the type of signal to be measured or processed. Data-acquisition systems, for instance, can lead to very complex spatial structured systems. Complete software-configured measurement systems can be put together with use of a computer and some interfacing cards. The relevant information is implied in the structure of matter itself and can only be retrieved by measuring the response gained when the object is subjected to a suitable stimulus.
