Patent ID: 8000023
Filing Date: 2011-08-16
Classification: G02B

Abstract:
1. A zoom lens adapted to be disposed between a magnified side and a reduced side, the zoom lens comprising: a first lens group disposed between the magnified side and the reduced side and having a negative refractive power, the first lens group comprising a first lens, a second lens, a third lens, and a fourth lens arranged in sequence from the magnified side toward the reduced side, wherein refractive powers of the first lens, the second lens, the third lens, and the fourth lens are respectively positive, negative, negative, and positive; and a second lens group disposed between the first lens group and the reduced side and having a positive refractive power, the second lens group comprising a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, and an eleventh lens arranged in sequence from the magnified side toward the reduced side, wherein refractive powers of the fifth lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens, the tenth lens, and the eleventh lens are respectively positive, negative, positive, negative, positive, negative, and positive, and wherein the eighth lens, the ninth lens, and the tenth lens together form a triple cemented lens.