singlet state of the molecular oxygen u201c singlet oxygen u201d may develop from a collision complex between an indicator molecule and molecular oxygen which is in the state of excitement by the transmission of energy from the indicator molecule which singlet oxygen after diffusive separation of the collision complex returns into the ground state either without radiation or while emitting radiation at a wavelength of 1270 nm or is deactivated by the polymer matrix without radiation or causes a chemical reaction and hence a conversion of the indicator or causes a chemical reaction with the matrix thus changing the molecular environment of the dye that extremely reactive singlet oxygen may however be deactivated also according to the invention by the stabilizing additives admixed either by energy transfer charge transfer or a chemical reaction or by combinations of these mechanisms thus no longer endangering the sensor when selecting the agents or additives it should be safeguarded in all of the embodiments that the substances added do not create a strong background luminescence or do not substantially alter the photophysical properties or even the chemical consistency of the indicator so as to no longer guarantee the function of the sensor moreover a high volatility of the substances added would undo the advantages of stabilization in particular if the photophysical properties of the indicator were influenced by the substance added which properties would also change with a changing concentration of the substance added the following examples of negative influences of additives on the photophysical properties of certain sensor types may be given 1 oxygen sensors.