Patent ID: 8842361

Claim:
A mode-locked laser system comprising: a seed laser capable of providing an input laser signal; an input tap joined to said seed laser capable of collecting a portion and transmitting a remainder of the input laser signal; a plurality of amplifier stages configured in series and joined to said input tap to receive the remainder of the input laser signal at a first amplifier stage and provide an amplified laser signal from a final amplifier stage; an output tap joined to the final amplifier stage capable of collecting a portion and transmitting a remainder of the amplified laser signal, the transmitted remainder being providable as mode-locked laser output; and a free-space coupler in optical communication with said input tap and said output tap, said free-space coupler configured to combine the input tap collected portion and the output tap collected portion into a feedback laser signal, said free-space coupler being joined to said input tap to couple the feedback laser signal to the remainder of the input laser signal at the input tap.