Zoom lens system, image pickup device and digital device

An image pickup apparatus, comprising:

• a zoom lens system, and
• an image pickup element,
• wherein the zoom lens system comprises, in order from an object side:
• a first lens group having a negative optical power,
• a second lens group having a negative optical power, and,
• a third lens group having a positive optical power,
• wherein the position of the first lens group is fixed during zooming, and the third lens group comprises three single lenses including, in order from the object side, a third-first lens being a single lens having a positive optical power, a third-second lens being a single lens having a negative optical power and a third-third lens being a single lens having a positive optical power, and
• wherein the following conditional expression (1) is satisfied:
• 0.35<L3/f3<1.5 (1)
• where L3 represents the axial air gap distance between the third-second lens and the third-third lens and f3 represents the focal length of the third lens group.

A digital device, comprising:

• a zoom lens system;
• an image pickup element;
• a signal processing section to conduct a predetermined processing for image signals produced by the image pickup element;
• and
• a controller to control zooming of the zoom lens system and image pickup;
• wherein the zoom lens system comprises, in order from an object side:
• a first lens group having a negative optical power,
• a second lens group having a negative optical power, and,
• a third lens group having a positive optical power,
• wherein the position of the first lens group is fixed during zooming, and the third lens group comprises three single lenses including, in order from the object side, a third-first lens being a single lens having a positive optical power, a third-second lens being a single lens having a negative optical power and a third-third lens being a single lens having a positive optical power, and
• wherein the following conditional expression (1) is satisfied:
• 0.35<L3/f3<1.5 (1)
• where L3 represents the axial air gap distance between the third-second lens and the third-third lens and f3 is the focal length of the third lens group.