Crack open a modern zoom lens and the sticker shock on a repair quote starts to make sense. Inside the barrel: multiple optical groups suspended on helicoids, a geared focus or zoom-drive assembly, a small motor, and a nest of wiring running to electronic contacts. None of it is built to be casually taken apart, and that’s exactly the point. The parts you never see The front element’s purple-green iridescence isn’t decorative — it’s multi-layer anti-reflective coating, applied in a vacuum deposition process to suppress flare and ghosting.