An operation apparatus is responsive to a physical action for inputting a control parameter of a musical sound into an electronic musical instrument. Advantageously, the matrix includes at least one logic sector with pairs of rows or word lines being short-circuited with each other and referring to a respective biasing terminal, one for each pair, and in that the row decoding circuit portion includes a single select block which controls a single multiplexer for the logic sector for the regulation of the signals applied to the biasing terminals. a luminescence biosensor, comprising a multi-layer structure. Any indexing technique may be used. Accordingly, it is possible to realize a slim display apparatus.