Will the lens of Canon 70200 lens not expand and contract when the third generation lens rotates the focal length?

Telescopic. The third generation lens of Canon 70200 lens The third generation lens of Canon 70200 lens adopts the design of rotary zoom. When zooming, the lens will become shorter or longer with the focal length, so it will expand and contract. In film and television, the lens has two fingers, one refers to the optical components used by film cameras and projectors to produce images, the other refers to the continuous picture taken from power on to power off, or the fragment between two editing points, also known as the lens.