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Standard zoom lens

Image Number 11 for United States Patent #5563739.

A zoom lens has a first lens unit having a negative refractive power as a whole, and a second lens unit having a positive refractive power as a whole, and effects zooming by changing the air gap between the first and second lens units. The first lens unit has a first negative meniscus lens with a concave surface having a more intense curvature and facing the image side, a second negative meniscus lens with a concave surface having a more intense curvature and facing the image side, and a positive lens with a convex surface facing the object side. The second lens unit has a positive lens component having at least two positive lenses, a negative lens component, and a positive lens component. At least one of the lens surfaces constituting the first lens unit is an aspherical surface. The zoom lens satisfies the following conditions:

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