Sensor system for gases and vapours

摘要

The invention relates to a sensor system for gases and vapours having a two-beam arrangement which contains as light source a luminiscent diode (LED) and as receiver a reference diode and a measuring diode, of which at least the measuring electrode has a colour filter assigned to it whose optical transparency adjusts in an analogue manner to the partial pressure of a gas to be measured. According to the invention the measuring diode (4) and the reference diode (5) each have an amplifier (6, 7) connected downstream, to which is connected respectively a series circuit of an integrator (8, 9) having a switch (10 and 11) and whose outputs are connected to a differential amplifier (13) whose output lead contains a third switch (12), and a common control device (21) is assigned to the switches (10 to 12). This sensor system requires only a low expenditure and enables a measurement independent of extraneous light and of intensity fluctuations of the transmitter diode (3). <IMAGE>