A line pair, often abbreviated as 1p, consists of two black parallel lines separated by a white space, typically arranged on an optical test chart. This pattern is used to measure the resolution of a camera lens or imaging system, determining how finely it can reproduce detail.
Understanding line pairs is important for photographers, lens testers, and imaging professionals who want to evaluate and compare lens sharpness. By analyzing how many line pairs per millimeter a lens can resolve, you can assess its ability to capture fine details accurately, which is critical for technical, scientific, and high-quality photographic work.