Patent ID: 8649012

Claim:
An optical gas sensor comprising: a light-emitting diode; a photosensor; a measuring section between the light-emitting diode and the photosensor; and a control and analyzing unit determining a concentration of a gas in the measuring section from a light intensity measurement by the photosensor, the control and analyzing unit measuring a forward diode voltage over the light-emitting diode at a known current and determining a temperature of the light-emitting diode from the forward diode voltage detected over the light-emitting diode based on a preset dependence of the forward diode voltage on temperature, and applying a correction function that is a function of the light-emitting diode temperature determined, with which the measurement is converted to that of a preset temperature of the light-emitting diode, the control and analyzing unit reducing measuring uncertainty, which increases with rising temperature of the LED, by adjusting a radiation output of the LED to a preset constant radiation output.