Raman Diagnostics Instrumentation System: Schematic of the Raman instrumentation system that enables quantitative chemical species and temperature measurements in high pressure flames. The 10 Hz pulsed Nd:YAG laser operating at 532 nm provides 1000 mJ pulses which are stretched using a pulse-stretcher that is comprised of a series of optical ring-cavities that serve as optical delay lines. The output from the pulse-stretcher is then directed to the measurement zone above a high pressure burner. The laser beam is folded over the measurement zone using a lens and prism to effectively double the scattered signal. The Raman scattered signal is collected at a 90 degree angle relative to the beam propagation direction using a high speed camera lens that is fiber optically coupled to a high speed electromechanical shutter (patent pending) that provides optical gate times as short as 9 _s. The shutter reduces the background luminosity from flames by a factor of 1000x. the signal then is dispersed using a high speed holographic axially transmitting spectrograph and detected using a backside-illuminated CCD array that provides up to 90% quantum efficiency. The actual sampled probe volume is defined by the beam waist diameter and the lens/fiber collection system, and is approximately 1 mm in diameter by 1.6 mm long.