Apparatus and method for intensifying illumination brightness by time-superposing multiple pulsed light sources

An illumination apparatus comprising:

• at least two light sources, each of which produce independent light beams,
• a controller for sequentially driving each of the light sources at a high power above their respective maximum rated power, to produce a respective light beam for each light source, and for leaving the remaining light source at a low power below their respective maximum rated power, such that the time-average of the high and low power levels are set to a predetermined value for each o the light sources,
• combining and directing means for sequentially combining each of the light beams from their respective light sources while being driven at high power into a common output beam with a fixed direction;
• said at least two light sources comprise first and second light sources in which the produced light beams from each light source have a first and a second polarization, and wherein the combining and directing means comprises an optical system;
• first and second sets of light guides corresponding to the first and second light sources, each individual light guide having two pairs of substantially parallel surfaces,
• first and second pairs of lenslet arrays corresponding to the first and second light sources for focusing the light from individual lensets into a corresponding individual light guide,
• a polarizing beam splitter array for directly transmitting the light of the first polarization from each of the first and second sets of light guides, and transmitting the light of the second polarization from the first and second sets of light guides after reflection from the substantially parallel surfaces, and half-wave retarding strips for converting either the directly transmitted light of the first polarization or the twice-reflected light of the second polarization to match the other of the polarization components.