ZOOM ASSEMBLY WITH PLURAL LENS GROUPS MOVED INTEGRALLY OR SEPARATELY FOR ZOOM ADJUSTMENT AND FOCUSING

PROBLEM TO BE SOLVED: To provide a very compact zoom assembly capable of conducting focusing in plural zoom positions without using a guide rod, using only one motor for zoom adjustment and the focusing. SOLUTION: This zoom assembly is provided with a zoom lens 10 for specifying an optical axis 17. The zoom lens 10 has two endmost zoom positions (a wide angle position and a telephoto position) and plural intermediate zoom positions, and is provided with a first movable lens groups 12, 16 and a second movable lens group 14. The first movable lens groups 12, 16 and a second lens movable lens group 14 are moved integrally in the same direction with the same speed when focused in one out of the endmost zoom positions and one out of the intermediate zoom positions, and they are moved separately when focused in the other position of the endmost positions.