Canon files patent for RF 28-135mm F4 IS internal zoom lens

Canon has disclosed a new optical patent for an RF 28-135mm F4 IS full-frame zoom lens featuring an internal zoom design. Filed in early February 2025, the patent suggests a focus on the video production market.

By utilizing an internal zoom mechanism, the lens maintains a constant physical length during focal length adjustments. This feature is particularly beneficial for videographers using gimbals or cage systems, as it prevents shifts in the center of gravity. The design aims to balance a compact form factor with high image quality across a wide-to-telephoto range.