DARPA takes aim at lighter optics

If a new research program is successful, warfighters may soon be using lighter optics gear such as night vision lenses and laser communications equipment.

According to the Defense Advanced Research Projects Agency, which launched the initiative, while the last several decades have seen the size and weight of many electronic systems go down through miniaturization, the same thing hasn’t happened with optics. Optical systems’ digital components might have gotten smaller, but the lenses themselves haven’t changed much over the years.

DARPA wants to change this through a program to create new ways to manufacture lenses to greatly reduce their size and weight. This would have a major impact on a variety of military systems such as laser target designators, night vision gear and laser-based communications systems.

The Manufacturable Gradient Index Optics (M-GRIN) program takes advantage of recent advances in how lenses are designed and manufactured. It will use advanced modeling techniques to quickly develop and test new types of lenses from a range of materials, such as polymers, for better performance across the spectrum.

“In the past century, every component of an optical system has become lighter and smaller, except the optics,” Stefanie Tompkins, M-GRIN program manager, said in a DARPA statement. “The impact of smaller, lighter optics on anything used to focus light, from contact lenses and corneal implants to lasers and solar arrays would be enormous.”

One advantage of the new manufacturing technologies is that optics can now be shaped to fit a system, rather than making the system conform to the optics, which results in reduced size, weight and assembly costs. She noted that the capability allows the manufacture of a few custom lenses at any time during a high-volume production run without increasing unit cost.

M-GRIN will allow developers to rapidly design, prototype and test new systems throughout the development process. Additionally, DARPA officials noted that the tools developed for the new optics process with push research of GRIN lens design and fabrication methods into new areas.

The program’s first phase began in September 2010 and will conduct its preliminary design reviews in the next month on two challenge areas: wide field-of-view solar concentrators and lightweight night vision goggles. This first phase emphasizes technology development and seeks to expand the range of GRIN lens materials and to extend commercial design tools to accommodate M-Grin lenses, DARPA officials said. Future work will emphasize manufacturability, with the goal of reaching low rate initial production by September 2013, they said.