Patent ID: 8208503

Claim:
A broadband light source configured to emit a stable broadband optical beam, the broadband light source comprising: at least one optical pump source; an optical system including a polarization beam combiner, the optical system configured to receive at least one optical pump beam having a respective at least one pump coherence length from a respective one of the at least one optical pump source, and from that at least one optical pump beam produce a substantially unpolarized pump beam as a first output; and a solid state laser medium to receive the substantially unpolarized pump beam from the first output of the optical system and emit a stable broadband amplified spontaneous emission back to the optical system, wherein the stable broadband amplified spontaneous emission is output from a second output of the optical system; wherein the optical system further includes a polarization maintaining splitter having a tap ratio substantially close to 50%, the polarization maintaining splitter configured to receive the at least one optical pump beam from a respective one of the at least one optical pump source at a respective input and to output first and second optical pump beams having substantially equal amplitudes and polarizations, wherein the first and second optical pump beams propagate along respective first and second optical paths, wherein one of the first and second optical paths includes a rotational component, wherein the rotational component rotates the polarization of one of the first and second optical pump beams with respect to the polarization of one of the respective second and first optical pump beams, wherein the first and second optical paths have a length difference greater than the at least one pump coherence length, wherein the polarization beam combiner receives the orthogonally polarized first and second optical pump beams propagating along the first and second optical paths, respectively, wherein the polarization beam combiner outputs the substantially unpolarized pump beam; and a wavelength division multiplexer coupler configured to receive the substantially unpolarized pump beam, wherein a first output of the wavelength division multiplexer directs the substantially unpolarized pump beam to the solid state laser medium and wherein the stable broadband amplified spontaneous emission is output from a second output of the wavelength division multiplexer.