Zoom lens and electronic imaging apparatus using the same

A zoom lens comprising, in order from an object side:

• a first lens unit with negative power;
• a second lens unit with positive power;
• a third lens unit with positive power;
• and
• a fourth lens unit,
• wherein when a magnification of the zoom lens is changed in a range from a wide-angle position to a telephoto position, spacing between the first lens unit and the second lens unit is narrowed and spacing between the second lens unit and the third lens unit is widened;
• an aperture stop moved integrally with the second lens unit is interposed between a most image-side lens element of the first lens unit and a most image-side lens element of the second lens unit;
• and the first lens unit consists of a first lens element with negative power placed on the object side and a second lens element with positive power placed on an image side and satisfies the following conditions:
• 0.15<φIMF/φIMR<1.0
• −3.0<φIPF/φIPR<−1.0
• where φIMF is a power of an object-side surface of the first lens element with negative power of the first lens unit, φIMR is a power of an image-side surface of the first lens element with negative power of the first lens unit, φIPF is a power of an object-side surface of the second lens element with positive power of the first lens unit, and φIPR is a power of an image-side surface of the second lens element with positive power of the first lens unit.