Tests performed by the Naval Research Laboratory in Washington have found that the Ocean Portable Hyperspectral Imager for Low-Light Spectroscopy produces highly linear spectral and radiometric responses while imaging coastal environments.

The push-broom scanning device may be useful for applications such as measuring water depths, detecting submarines and submerged hazards, and monitoring the health of coral reefs.

According to a report in the Feb. 24 issue of Optics Express, the two key elements in the accuracy of the imager are the VS-15 Offner spectrograph from Agilent Technologies in Fitchburg, Mass., which minimizes smile and keystone distortion, and a thinned back-illuminated CCD camera from PixelVision Inc. in Beaverton, Ore., which has high quantum efficiency when detecting blue frequencies.