What does the term “near-infrared” refer to in NVG technology?

The term "near-infrared" in NVG technology specifically refers to a range of light wavelengths that are just beyond the visible light spectrum, typically from about 700 nanometers to 1000 nanometers. This range is crucial for night vision devices as they utilize this wavelength to enhance visibility in low-light conditions. Near-infrared light is not visible to the human eye, but it can be detected by specialized sensors in NVGs, allowing them to amplify this light to create a viewable image. This capability makes NVGs effective for operations in darkness, where visible light is minimal or absent.

The other options do not accurately describe near-infrared technology in this context. While batteries are important for NVG functionality, they don’t relate to the term "near-infrared." Enhancing color vision does not pertain to the functioning of NVGs, which primarily work with light outside the visible spectrum. Similarly, heat detection is a different technology associated with thermal imaging rather than near-infrared light detection. Hence, option B stands as the accurate description within the context of NVG technology.