Army seeks to upgrade night-vision goggles.

• Author: Peck, Michael

Experts at the Army's night-vision laboratory predict that a new generation of goggles now in development will fix some of the shortcomings in existing devices, such as image quality and the ability to see through smoke and dust.

The essence of these new goggles is "sensor-fusion," which combines conventional night-vision technology (called image intensification or I2) and thermal sensors (forward-looking infrared).

The I2 wavelength offers a clearer image and can see through glass windows. However, image intensification requires that there be sufficient light to intensify, which makes it ineffective in an Afghan cave. For example, "there was an immediate interest in IR [infrared] on the head when we went to Afghanistan, because of the caves," said A. Fenner Milton, director of the Army's Night Vision and Electronic Sensors Directorate.

On the other hand, IR relies on thermal contrast--heat emitted by the target versus the heat emitted by its background--which provides images with better contrast than 12, and can see through obscurants such as dust and smoke. "It requires very little temperature difference between the target and its background for the sensor to detect the target," said Milton.

The Army is combining the best of both technologies by creating fusion goggles that combine IR and I2 into a single image. These will replace some of the I2-only goggles, such as the PVS-7 and PVS-14.

Fusion goggles have been made possible by the development of uncooled IR sensors that has significantly reduced the weight of once-bulky IR devices. "They utilize both IR and 12 technologies and fuses them into a single picture," Milton said.

Milton predicts that within a couple of years, many American soldiers will have "IR on the head," via lightweight fusion goggles. "I think all the combat troops will have some form of IR," he added.

Current fusion goggles weigh 2 pounds (battery pack included) and allow field of vision 40 degrees horizontal and 30 degrees vertical. The sensors have selectable channels, from 100 percent near infrared to 100 percent long-wave Infrared. The batteries provide four hours of continuous operation.

Other technologies intruded to help enhance night-vision capabilities include range-gated lasers and 3rd generation forward-looking infrared systems.

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