An optical imaging arrangement includes an optical projection system and a support structure system. The profiled journal is a hollow journal comprising a material with a substantially uniform wall thickness with a maximum deviation of \xb115%. Some of the disclosed illumination systems make use of light sources of different colors, and provide polarization conversion in ways based on color-selective elements of a variety of different types to convert substantially all the light emitted by the light sources to a single polarization, without increasing the effective optical extent of the source.