Earlier this month, the Raytheon Company delivered the 25,000th AN/PAS-13 Thermal Weapon Sight (TWS) to U.S. Army officials from Program Executive Office Soldier. This milestone marked the success of a 17-month production ramp-up that accelerated delivery of urgently needed equipment to U.S. warfighters in the Middle East.

Marlow Industries, Inc. (Dallas, Texas), a subsidiary of II-VI Incorporated, has participated in the U.S. Army's TWS program for more than 25 years. Founded in 1973, Marlow is a global leader in the design and manufacture of thermoelectric solutions for both cooling and power generation based on compound semiconductor materials. Marlow's products are sold in a variety of markets, including defense, space, photonics, telecommunications, medical, consumer, and industrial.

Raytheon (previously Texas Instruments and Hughes Aircraft Company) has provided the AN/PAS-13 advanced thermal imaging family of systems for mounting on rifles, machine guns, and other imaging platforms. The Forward Looking Infrared (FLIR) system has been used during many wars, conflicts, and special operations that imposed severe operating environments on the system. The system had to be "ruggedized" to withstand the shock impacts of gunfire and rough handling imposed by the rigors of battle. The FLIR system enables the operator (soldier, seaman, or policeman) to "see" at night in pitch darkness without the presence of any light source.

The thermal emission (infrared) detector made by Raytheon is cooled to cryogenic (low) temperatures by a Thermoelectric Cooler (TEC) manufactured and mounted into a lower vacuum assembly by Marlow. The infrared detector focal plane array is scanned with thermal imagery by a rotating mirror that views the battlefield and presents a "TV-like" picture to be viewed by the operator. Personnel, hot bean pots, tanks and other vehicles, and snipers in rural settings are clearly seen and identified to enable the operator to direct gunfire at chosen targets.

Since the TWS system was designed to be man-portable, each component in the system had to be lightweight, small, and operate on low power from internally contained batteries. Marlow worked with Raytheon’s design engineers to evolve to a low-power, optimized six-stage cooler design that would fit into a small vacuum housing. Since the optical line of sight had to be "built in" such that no secondary alignment was required during system assembly, the TEC had to be manufactured and mounted into the vacuum housing with precision exceeding tenths of thousands of an inch. Tools, processes, and fixtures were developed by Marlow that accomplished this precision manufacturing while ramping production rates up to 1,000 units per month. This production rate enabled Raytheon to also deliver systems at that rate in order to meet the needs of the special forces who are serving our country in the global war on terrorism.

Many different versions of the six-stage TEC have evolved over 25-plus years to meet ever increasing demands and performance. Marlow was the chosen supplier from the start of the program and has been the sole source for the TECs over the entire program, which is still underway.

Bill Kolander of Marlow Industries states that the TWS program has been one of the most successful production programs ever implemented at Marlow Industries. The long-term working relationships that have evolved over the years since the inception of the TWS program between companies now owned by Raytheon (Texas Instruments and Hughes Aircraft) and Marlow Industries has greatly contributed to the success of the program, he said. He went on to say that the critical factors for success were driven by the vital need for the Infrared Focal Plane Array (IRFPA)—the "seeing eye" of the system—to operate at a deeply cooled cryogenic temperature provided by the Marlow multistage, low-power, small, rugged, solid-state TEC.

On August 9, 2005, Barry Nickerson, President of Marlow Industries and member of the Board of Directors of the National Association of Manufacturers (NAM), presented Congressman Jeb Hensarling with NAM's Award for Legislative Excellence at a Marlow company meeting. This award goes to senators and representatives whose records on key manufacturing votes demonstrate an understanding of—and support for—the manufacturing sector's key role in our economy and society. Congressman Hensarling was presented with the NAM Award for his consistent support of pro-growth, pro-manufacturing, and pro-worker policies.

Congressman Hensarling shared his appreciation with and thanked Marlow employees for their critical technological support and contributions to our country’s defense/military and warfighters on programs such as the TWS. He then toured the Marlow manufacturing facilities, spoke with employees, viewed the TWS TEC/vacuum assembly, and received a briefing on the technology developments being performed in order to accelerate innovations for defense and space applications.

"I was pleased to tour Marlow Industries and meet with their wonderful employees,” Congressman Hensarling said, adding that “Marlow is an asset to our community and our country, playing a critical role in the future development of our military, scientific, medical, and industrial markets."