Patent ID: 6943962

Claim:
A zoom lens system comprising in order from an object side to an image side: a first lens unit having a negative optical power, the first lens unit consisting of a meniscus-shaped negative lens element whose convex surface faces the object side and a positive lens element; a second lens unit having a positive optical power; and a third lens unit having a positive optical power, the third lens unit comprising a positive lens element having a convex surface on the object side; wherein the zoom lens system performs zooming by changing a distance between the first lens unit and the second lens unit as well as a distance between the second lens unit and the third lens unit; and the following conditional expressions are satisfied: 1.60 <n 1 n< 1.75 1.65 <n 1 p< 1.80 where n 1 n represents a refractive index of a material of the negative lens element in the first lens unit, and n 1 p represents a refractive index of a material of the positive lens element in the first lens unit.