Fluorescence imaging illumination fiber including a first fiber, a second fiber, and a diffuser, the second fiber concentrically enfolding the first fiber, the diffuser is coupled at the end of the first fiber and the second fiber, the first fiber having a first angular output, the second fiber having a second angular output, the diffuser increasing the first angular output by a first value and increasing the second angular output by a second value, the first value exceeding the second value.
