Scalable and Modular Diode Laser Architecture for Fiber Coupling that Combines High-Power, High-Brightness and Low Weight - Photonics West 2014
We have developed a scalable and modular diode laser architecture that combines high-power, high-brightness, and low weight that fulfills these requirements for a multitude of applications. At the heart of the concept is a specially tailored diode laser bar with an epitaxial and lateral structure designed such that only standard fast- and slow-axis collimator lenses are required to couple the beam into a 200μm core fiber with a numerical aperture (NA) of 0.22. To fulfill the requirements of scalability and modularity, a reduced size heat sink populated with multiple tailored bars is used. This enables a compact and lightweight design with minimum beam path length. The design concept is capable of providing single wavelength, high-power laser diode modules, with optional volume holographic gratings for wavelength stabilization. Modules with output power levels of more than one kW at a power-to-weight ratio of less than 1 kg/kW are achievable. In this paper, two laser modules based on this concept are presented. The optical output power is above 500W at a module weight less than 500g and 300W at 300g. Both modules are coupled into a 200μm, 0.22NA fiber.