What type of lighting can optical detectors not detect?

The correct answer highlights the limitations of optical detectors in sensing specific types of lighting. While optical detectors are adept at detecting visible light, they typically have difficulty with certain frequencies or types of illumination, such as fluorescent and incandescent lighting.

Fluorescent lights operate by exciting gas within a tube, causing it to emit light at specific wavelengths, which can sometimes fall outside the optimal sensitivity range of some optical detectors. Incandescent lights emit a continuous spectrum of light but can also produce heat and infrared emissions that optical detectors may not register effectively. Additionally, the flicker rate of fluorescent lights can confuse detectors, leading to detection challenges.

In contrast, other types of lighting, like LED and natural sunlight, generally fall within the detectable spectrum for optical sensors. Infrared lighting, although outside of the visible spectrum, can also be detected with dedicated optical equipment designed to sense infrared wavelengths. Therefore, the distinction in technology and how these sources emit light underpins the correct choice regarding what types of lighting optical detectors cannot effectively perceive.