High power laser diode and application

In general, an electrical to optical power conversion efficiency for a high power LD ranges from 40 to 50%. Therefore, 50 to 60% of the input electricity is transformed into heat. The generated heat degrades the LD's optical characteristics and their lifetimes dramatically. We must not only suppress the heat generation but also remove the heat effectively from the LDs. Several years ago we proposed "FUNRYU", a water cooled heat sink. The sink has great advantages, due to its simpler structure than a micro channel cooler, in terms of cost, productivity, and water pressure.