Biometric security systems that can identify individuals à la Minority Report based on the unique patterns in their irises have been touted as a fast, accurate and efficient way to control access to sensitive information and facilities. But until now, their reach has literally been limited.

The iris's fine texture tends to remain stable throughout one's life. But one of the biggest factors working against iris-scanning biometrics, particularly at law-enforcement facilities and military bases in hot zones such as Iraq and Afghanistan, is the difficulty in obtaining a clear iris scan from a distance of more than a few dozen centimeters.

Researchers are working on this problem by developing technology that will not only enable iris scanning at distances of up to about 12 meters, but will also simultaneously scan a person's face to more accurately identify those seeking access. Iris and facial recognition should be part of the same biometric identification system, says Marios Savvides, a Carnegie Mellon University professor of electrical and computer engineering who directs the school's CyLab Biometrics Lab in Pittsburgh.

"The iris is part of the face," he adds, "so why not use both?"

The U.S. Department of Defense (DoD) agrees, and in April it awarded Savvides and his team $1.5 million to help further their work with the hope that it will help the military better secure its facilities worldwide. "We are developing a system for the war-fighter that scans irises from eight to 12 meters away," Savvides says. "Anywhere in that distance, the camera will autofocus and get an image of the person's iris."

The main goal behind this specific project is to help soldiers and security contractors enroll in a biometric security system foreign law enforcement, workers and others seeking access to military bases in Iraq and Afghanistan. This system will include a camera that can capture a highly detailed digital image of a person's iris (the pigmented muscle surrounding the pupil responsible for controlling the amount of light reaching the retina), computers that store the image in a database, and software that can compare the irises of persons seeking access against that database. If there is a match, the person may be granted access to the facility. If there is not, the person likely does not have clearance to enter.

Although iris-scanning technology exists already (made by companies including LG Electronics, Sarnoff Corp. and AOptix Technologies, to name a few), Savvides and his colleagues are designing their system to help security personnel to keep a greater distance from those being scanned.

Current biometric systems require significant cooperation between guards and the soldiers, local law enforcement, and others who are enrolled in the system, he says, at times requiring security personnel to lay down their weapons in order to capture the iris image. LG's handheld IrisAccess device must be placed within 25.4 centimeters of the eye being scanned, whereas the Aoptix Insight 2 offers scanning at a distance of up to two meters.

CyLab is also working on a facial-landmarking component to integrate with the iris-scanning technology, and the lab has offered the DoD software that can create 3-D facial images as another layer of biometric security. The facial-landmarking software notes the location of a person's facial features (including the specific position of an individual's eyes, nose, mouth and even scars) and, like iris recognition, compares these features against a database of images of approved personnel. The 3-D component, which is not part of the Defense Department project but will be used by the FBI, can create 3-D images of a person's face that can be rotated to match the angle of a face captured on video. This process should take only a few seconds, Savvides says, whereas previous attempts to create 3-D models from 2-D facial images took several minutes.

Savvides expects to deliver an iris-scanning and facial-landmarking system to the DoD by next summer that includes an autofocus camera, a light source near the infrared range that can illuminate the iris while reducing reflections from the cornea, and the software required to match scanned iris images against a database of approved (or restricted) personnel.

The government plans to have this technology in the hands of the military and law enforcement by 2012.