The focus of this research work was to develop an optical hybrid rocket engine that regression rates, various flame characteristics, and other chamber characteristics can be measured using conventional cinematography. For the current experimental series, hydroxyl-terminated polybutadiene (HTPB) or nylon PA66 fuels and gaseous oxygen were the reactants. Images of both the plume and the chamber interior were ascertained since the chamber was equipped with quartz and Plexiglas windows at capture rates from 2000 to 4000 frames per second. From the fourteen experimental test fires, the quartz windows were used for five tests and sustained the combustion event while maintaining a steady-state pressure of approximately 1.0 to 3.5 MPa. The gaseous oxygen was delivered at mass flow rates of 35 to 75 g/s and the thrust levels produced were 130 to 300 N.