Giving New Life to Laser Diodes

by Joe Singleton/jsingleton@nttc.edu

A new MDA-funded technology designed to increase the performance and reliability of laser diodes soon could reduce costs for the industrial welding and biomedical markets.
Science Research Laboratory, Inc. (SRL; Somerville, MA), an innovator of power supplies, is extending the life of laser diodes with an innovative solid-state controlling mechanism, commonly referred to as an intelligent driver. This driver can interrupt and reset a diode’s power supply by monitoring and responding to dynamic current and voltage signatures that indicate the device is close to failure. The technol-ogy provides laser operators a tenfold cost savings over operating systems not using an SRL driver by enabling the diodes to operate at high power 10 times longer.

SRL’s ultra-compact solid-state drivers are now being incorporated into a high-energy defense-related laser system. SRL’s subcontract on this project had its origins in SBIR Phase I and Phase II contracts from MDA, which directed the company to design and test a driver technology that would improve the performance and lifecycle of laser diodes. The Phase II contract was extended in summer 2007 by one year, until June 2008, so the company could “take on manpower and work on the [high-energy laser] project,” said company president Jonah Jacob.

Based upon what they had heard from MDA officials regarding the SBIR Phase II contract’s success, planners of the high-energy laser project asked Jacob to contact a prime systems integrator, which needed a method to improve the lifecycle of laser diodes. SRL was awarded a subcontract to incorporate its solid-state driver technology into the system.

The defense industry is banking on SRL to deliver a driver that can increase the lifecycle of laser diodes and reduce the high associated costs. Jacob said that a 2.5-kilowatt laser-diode array costs between $25,000 and $30,000 for a stack of 600 diodes. A laser module typically uses about 80 stacks, which would put the total cost between $2 million and $2.4 million. A diode operated at high power lasts about 100 hours, or just over four days. But with SRL’s driver technology, the same diodes could last for 1,000 hours.

SRL is considering expanding beyond the defense realm, into commercial markets that involve such applications as biomedicine, laser cutting, and laser welding. The biggest challenges facing the company in the commercialization phase will be gaining market acceptance and licensing the technology. Despite the plans, Jacob said tapping these markets may still be long into the future, as SRL is currently focused on the defense laser market.