Abstract: The present application provides an optical probe system for use with a combustion flame in a combustion chamber. The optical probe system may include a number of optical probes fixedly attached about the combustion chamber and positioned such that the optical probes collect light generated by the combustion flame in a field of view of each of the optical probes. One or more components external to the combustion chamber may produce and analyze signals indicative of the light generated by the combustion flame in the field of view of each of the optical probes.

Abstract: A gas species monitoring system includes a laser, a fiber amplifier configured to receive an input signal from the laser and generate an amplified signal, and a variable optical attenuation system configured to receive at least a portion of the amplified signal and generate an attenuated signal for delivery to a measurement point, where the measurement point includes a gaseous fluid. The system further includes a detector configured to receive and process a signal from the measurement point so as to obtain a measured signal that correlates with the presence of a gas species within the gaseous fluid at the measurement point, and a processor in communication with at least the variable optical attenuation system and the detector. The processor controls the variable optical attenuation system based upon the measured signal.