High power, fiber-coupled diode laser systems: system design and medical applications

Abstract

Summary form only given. Due to their high reliability, compact size, and ease of use, high power, fiber-coupled diode laser systems are attractive laser sources for surgical and therapeutic procedures. Applied Optronics Corporation has developed a system level approach to harnessing the optical power of multiple diode lasers and delivering that power through disposable optical delivery fibers fitted with standard optical connectors. The design is based on individual fiber-coupled diode lasers, whose individual output fibers are grouped together in a single optical connector. The total output power of the system scales linearly with the number of individual lasers. The emission wavelength or wavelengths of the system is determined by the choice of the individual lasers loaded into the system. A typical arrangement is one low power visible aiming laser and multiple high power infrared lasers. The individual lasers are arranged on a large thermal footprint, which limits the effect of mutual heating of adjacent lasers and allows for low intensity cooling techniques such as simple fans and heatsinking fins. The diode lasers themselves are single quantum well GRINSCH structures. The diode lasers are typically 100 pm wide 300 mW elements in the visible wavelengths, and 200 pm wide 1.8 watt elements at 980 nm. The laser output is coupled with efficiencies up to 75% into low NA (0.14) optical fibers. The users-supplied delivery fiber has a higher NA of 0.37 and a core size of 400 pm to 1000 pm depending on the system and total power requirements. The diode laser system itself is the size of personal computer, weighs less than 35 pounds, does not use cooling water and requires only a few amperes from a standard wall plug to deliver up to 50 Watt cw.