Zoom lens

Abstract

The invention relates to a zoom lens comprising a first lens group of positive focal power, a second lens group of negative focal power, a third lens group of positive focal power and a fourth lens group of positive focal power, which are sequentially arranged from an object end to an image end along an optical axis direction. All the first lens group, the second lens group, the third lens group and the fourth lens group can move along the optical axis direction in the zooming process so as to realize zoom. The zoom lens satisfies the condition formula: 0.15<|L3| / Lt<0.25, wherein L3 is a motion vector of the third lens group on an optical axis when the zoom lens zooms from a wide-angle end to a far end, and the motion vector is a positive value from the object end to the image end and is a negative value from the image end to the object end; and Lt is the total length of the zoom lens at the far end along the optical axis direction. The zoom lens provided by the invention has high zoom ratio and becomes thinner in the optical axis direction.

Description

technical field [0001] The invention relates to a zoom lens. Background technique [0002] It is the development trend of digital cameras to be thin, light, small and have a high zoom ratio. However, the current high zoom ratio lens needs to reserve a certain space for each lens group to move and zoom, so the thickness is relatively large. Contents of the invention [0003] In view of this, it is necessary to provide a zoom lens with a thin thickness and a high zoom ratio. [0004] A zoom lens, which includes a first lens group with positive refractive power, a second lens group with negative refractive power, and a A third lens group, a fourth lens group with positive refractive power. The first lens group, the second lens group, the third lens group and the fourth lens group can all move along the optical axis direction during the zooming process to realize zooming. The zoom lens satisfies the following conditional formula: [0005] 0.15<|L3| / Lt<0.25 [0006]...

AI Technical Summary

Problems solved by technology

However, the current high zoom ratio lens needs to reserve a certain space for each lens group to move and zoom for each lens group, so the thickness is relatively large.

Images