Wide angle variable-focus lens system for use in digital camera, has positive and negative group of lenses, which are arranged in sequence of object and change of focal length from shortest to longest focal length

摘要

The lens system has a positive group of lenses (10), a negative group of lenses (20), positive third group of lenses (30) and positive fourth group of lenses (40) arranged in sequence of the object. The change of focal length from the shortest to the longest focal length, increases the distance of the positive former group of lenses from the latter negative group of lenses. The distance of the latter negative group of lenses decreases from the positive third group of lenses, and the distance of the positive third group of lenses increases from the positive fourth group of lenses.