Multi-stage ytterbium fiber-amplifier seeded by a gain-switched laser diode

We demonstrated all-fiber amplification of 11 ps pulses from a gain-switched laser diode at 1064 nm. The diode was driven at a repetition rate of 40 MHz and delivered 13 µW of fiber-coupled average output power. For the low output pulse energy of 325 fJ we have designed a multi-stage core pumped pre-amplifier in order to keep the contribution of undesired amplified spontaneous emission as low as possible. By using a novel time-domain approach for determining the power spectral density ratio (PSD) of signal to noise, we identified the optimal working point for our pre-amplifier. After the pre-amplifier we reduced the 40 MHz repetition rate to 1 MHz using a fiber coupled pulse-picker. The final amplification was done with a cladding pumped Yb-doped large mode area fiber and a subsequent Yb-doped rod-type fiber. With our setup we reached a total gain of 73 dB, resulting in pulse energies of >5.6 µJ and peak powers of >0.5 MW. The average PSD-ratio of signal to noise we determined to be 18/1 at the output of the final amplification stage.

Long-term outcome of trans-scleral diode laser cyclophotocoagulation in refractory glaucoma

BACKGROUND: Long-term outcome and complications of diode laser cyclophotocoagulation (DCPC) may be important, since eyes, once treated with DCPC, are less likely to be subjected to other types of interventions in the further follow-up. METHODS: Retrospective review of 131 eyes of 127 patients treated from 2000 through 2004. Success was defined as intraocular pressure (IOP) at last visit 6-21 mm Hg; hypotony: IOP

[Revision surgery after carpal tunnel release using a posterior interosseous artery island flap]

The aim of this study is to evaluate the results of fasciocutaneous posterior interosseous artery island flaps in the treatment of recurrent or persistent carpal tunnel compression syndrome (CTS).