Fiber optics effectively extends the optical path of a viewing head allowing for greater flexibility in sighting flames. Two types of fiber optics are available in glass for oil and coal flame monitoring and quartz for all fuel types. The fiber optics assembly is custom built and may include outer carrier, inner carrier and fiber optic bundle, depending upon the application. The assembly may be flexible with rigid section or all rigid with engineered adapters for support at the burner end. Two types of lens assemblies are available; FOLC-SC provides straight angle of view, while FOLC- 9C provides for 9 degree skewed viewing angle. Different adapters, with or without air purge, are available for viewing end. All Honeywell 700 and 500 series signal processors and the U2 series all-in-one processor may be used with the fiber optic system.