ZOOM LENS AND IMAGING APPARATUS INCLUDING THE SAME

• Main Authors: IMAMURA MASAHIRO, UEDA MINORU, MOROOKA MASARU, KON TOYONORI
• Format: Patent
• Language: English; Japanese
• Published: 05.01.2015
• Subjects: ACCESSORIES THEREFOR; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USINGWAVES OTHER THAN OPTICAL WAVES; APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FORPROJECTING OR VIEWING THEM; CINEMATOGRAPHY; ELECTROGRAPHY; HOLOGRAPHY; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHOTOGRAPHY; PHYSICS

PROBLEM TO BE SOLVED: To provide a zoom lens advantageous in reducing the size of an optical system and ensuring a high variable power ratio, and an imaging apparatus including the zoom lens.SOLUTION: The zoom lens includes, in order from the object side: a first lens group G1 having positive refractive power; a second lens group G2 having negative refractive power; a third lens group G3 having positive refractive power; a fourth lens group G4 having negative refractive power; and a fifth lens group G5 having positive refractive power. When varying power, the first lens group, the second lens group, the third lens group, the fourth lens group and the fifth lens group are moved so as to change the distances between the lens groups. The distance between the first lens group and the second lens group, the distance between the third lens group and the fourth lens group and the distance between the fourth lens group and the fifth lens group are larger at the telephoto end than at the wide angle end. The distance between the second lens group and the third lens group is smaller at the telephoto end than at the wide angle end. The ratios of lateral magnifications of the third lens group and the fifth lens group at both zoom ends satisfy predetermined conditional expressions. 【課題】光学系の小型化と高い変倍比の確保に有利なズームレンズ及びそれを有する撮像装置を提供する。【解決手段】ズームレンズは、物体側から順に、正屈折力の第１レンズ群Ｇ１と、負屈折力の第２レンズ群Ｇ２と、正屈折力の第３レンズ群Ｇ３と、負屈折力の第４レンズ群Ｇ４と、正屈折力の第５レンズ群Ｇ５と、を有し、変倍の際に、第１レンズ群、第２レンズ群、第３レンズ群、第４レンズ群及び第５レンズ群の各々のレンズ群は、各々のレンズ群の間の距離を変化させるように移動し、第１レンズ群と第２レンズ群との間の距離、第３レンズ群と第４レンズ群との間の距離及び第４レンズ群と第５レンズ群との間の距離の各々は、広角端よりも望遠端にて長く、第２レンズ群と第３レンズ群との間の距離は、広角端よりも望遠端にて短く、両ズーム端における第３レンズ群と第５レンズ群との横倍率の比が所定の条件式を満足する。【選択図】図１