Patent ID: 7092147

Claim:
A broadband light source comprising: an optical amplifier including a plurality of amplifying mediums connected in series, said amplifier being configured for outputting forward and backward amplified spontaneous emission light over a wide wavelength range; a circulator comprising first to third ports and being connected in series to the optical amplifier, the second port of the circulator is configured to receive the backwardly outputted light from the optical amplifier and output the received light to the first port via the third port coupled the first port, and the first port is configured to output the light received from the third port and for returning the received light to the optical amplifier via the second port; a first pumping means located between the circulator and the optical amplifier, for pumping a pumping light to the optical amplifier; and a second pumping means located after the optical amplifier, for pumping a pumping light to the optical amplifier.