A laser illuminated projector system , comprising: multiple laser sources emitting Red, Green and Blue light beams, the Green laser source having a master oscillator/power amplifier structure including: a fiber seed laser operative to emit sub-nanosecond pulses of single mode signal light at a fundamental frequency in a propagating direction (A) along a light path, a fiber booster provided with a light-emitter-doped multimode core which has a bottleneck-shaped cross-section expanding toward a downstream thereof and receiving pulses of the single mode signal light, and a reflective element located downstream from the fiber booster and configured to receive and reflect pump light into the downstream of the multimode core in a counter-propagating direction, wherein the multimode core is configured to emit sub-nanosecond pulses of amplified signal light at the fundamental frequency in substantially a fundamental mode, and a single pass second harmonic generator receiving the pulses of amplified signal light and configured to double the fundamental frequency so as to generate sub-nanosecond pulses of Green light; and an Red, Green and Blue projector head configured to receive the Red, Green and Blue beams. multiple laser sources emitting Red, Green and Blue light beams, the Green laser source having a master oscillator/power amplifier structure including: a fiber seed laser operative to emit sub-nanosecond pulses of single mode signal light at a fundamental frequency in a propagating direction (A) along a light path, a fiber booster provided with a light-emitter-doped multimode core which has a bottleneck-shaped cross-section expanding toward a downstream thereof and receiving pulses of the single mode signal light, and a reflective element located downstream from the fiber booster and configured to receive and reflect pump light into the downstream of the multimode core in a counter-propagating direction, wherein the multimode core is configured to emit sub-nanosecond pulses of amplified signal light at the fundamental frequency in substantially a fundamental mode, and a single pass second harmonic generator receiving the pulses of amplified signal light and configured to double the fundamental frequency so as to generate sub-nanosecond pulses of Green light; and a fiber seed laser operative to emit sub-nanosecond pulses of single mode signal light at a fundamental frequency in a propagating direction (A) along a light path, a fiber booster provided with a light-emitter-doped multimode core which has a bottleneck-shaped cross-section expanding toward a downstream thereof and receiving pulses of the single mode signal light, and a reflective element located downstream from the fiber booster and configured to receive and reflect pump light into the downstream of the multimode core in a counter-propagating direction, wherein the multimode core is configured to emit sub-nanosecond pulses of amplified signal light at the fundamental frequency in substantially a fundamental mode, and a single pass second harmonic generator receiving the pulses of amplified signal light and configured to double the fundamental frequency so as to generate sub-nanosecond pulses of Green light; and an Red, Green and Blue projector head configured to receive the Red, Green and Blue beams. <EOS>