Product Code: ICAL05_903

Highly Reliable Diode Ensembles for Direct Diode Applications and Pumping Solid-State Lasers
Authors:
Andrew Leuzinger, JDS Uniphase; Santa Rosa CA USA
Presented at ICALEO 2005

High power (>20W) diode laser systems provide a relatively low-cost source of coherent radiation that is ideal for non-contact heating applications such as plastic welding, epoxy curing, heat treatment, selective soldering, and brazing. These applications generally require the diodes to be cycle on/off at frequency in the 0.25-4 Hz range. Historically bar diodes have been used in these applications. However, bar diode lifetimes are limited to around 10,000 to 15,000 hours when operated in a CW mode, and can be considerably less if the bar diodes are power cycled in the 1 Hz regime. In this paper we review lifetime data for JDSUs single-emitter 5W L3 diodes, and the advantages of combining multiple single-emitter diodes to obtain up to 100W diode laser systems. Diode lifetime data will focus on multi-cell, accelerated life testing, and will demonstrate individual diode MTBF numbers from >100,000 to >1,000,000 hours, depending on the operating environment. Diode ensemble reliability theory will be reviewed, and this will indicate that a 20,000 to 30,000 hour anticipated lifetime for a 100W ensemble should be a conservative estimate. We also will present data that specifically addresses power cycling of single-emitter laser diodes and lifetimes associated with this, and demonstrate that power cycling should not affect expected lifetime of an ensemble.