A fast and accurate zoom scope for use on military rifles has been developed by Sandia National Laboratories and its optical engineers.

The prototype system is called the Rapid Adaptive Zoom for Assault Rifles, or RAZAR, which allows a rifleman to toggle between high and low magnifications at a push of a button without having to remove their eyes from their targets or their hands from their rifles.

Development of the system was led by Sandia National Laboratories optical engineer Brett Bagwell, a former Army Special Forces officer who designed and built the first RAZAR from scratch and developed a manufacturing process for it.

The RAZAR prototype uses a patented active optical zoom system, called "adaptive zoom," invented by David Wick, who was working as a Sandia optical engineer at the time.

"Traditional optical zoom changes magnification by adjusting the positions of the lenses along the optical axis," Wick said. "For example, a 35-mm camera mechanically moves the lenses as you zoom in on or out from a subject.

"Adaptive zoom changes the focal lengths of two or more lenses by varying the curvature of the lenses' surfaces to provide optical zoom without changing their overall positions relative to one another, allowing the user to view either a wide-angle image or zoom in on an area of interest with a compact, low-power system."

Core technologies for the development of the RAZAR system include a polymer lens core with two flexible, hermetically sealed membranes, which encapsulate a polymer fluid; a piezoelectric actuator that electro-mechanically changes the flex of the lenses; and variable-focal length system design tools, including analytical expressions and computer models that trace rays of light through optical systems.

Sandia said RAZAR technologies are being considered for other uses, such as in medical imaging, binoculars, and cell phone cameras where optical zoom is needed to avoid the pixelated images associated with digital zoom.

Sandia National Laboratories is operated by Lockheed Martin subsidiary Sandia Corporation under a National Nuclear Security Administration contract.