Zoom lens and image pickup apparatus using the same

A zoom lens comprising in order from an object side:

• a first lens unit having a positive refractive power;
• a second lens unit having a negative refractive power;
• and
• a third lens unit having a positive refractive power, wherein
• the third lens unit having a positive refractive power comprises in order from the object side,
• a first lens component having a positive refractive power, and
• a second lens component having a negative refractive power in which, a lens having a positive refractive power and a lens having a negative refractive power are cemented, and
• the zoom lens satisfies the following conditional expressions (1), (2), and (3)
• 1.4<|f3—2p/f3—2n|<2.6 (1)
• nd3—2p−nd3—2n≧0 (2)
• nd3—2n≧1.8 (3)
• where,
• f3—2p denotes a focal length of the lens having a positive refractive power, in the second lens component having a negative refractive power, in the third lens unit having a positive refractive power,
• f3—2n denotes a focal length of the lens having a negative refractive power, in the second lens component having a negative refractive power, in the third lens unit having a positive refractive power,
• nd3—2p denotes a refractive index for a d-line of the lens having a positive refractive power, in the second lens component having a negative refractive power, in the third lens unit having a positive refractive power, and
• nd3—2n denotes a refractive index for the d-line of the lens having a negative refractive power, in the second lens component having a negative refractive power, in the third lens unit having a positive refractive power.