Ever since the early stages of space transportation in the 1940’s, and the related liquid propellant rocket engine development, combustion instability has been a major issue. High frequency combustion instability (HFCI) is the interaction between combustion and the acoustic field in the combustion chamber. It destroys the thermal boundary layer wall increasing heat transfer and could lead to compromised performance, and ultimately to destruction of the engine and mission loss. The main objective of this thesis is to take a few steps toward a better physical understanding of HFCI by experimentally investigating the interaction between flame and acoustic field in a combustor specifically designed for this research. With the large amount of collected data, well-defined spatially and temporally resolved acoustic fields of the first eigenmode were found with a high degree of consistency. These acoustic fields were successfully correlated with measured flame emission, and substantiated the conclusions with respect to coupling and driving mechanisms of HFCI.