Zoom lens system, imaging apparatus, and method for zooming the zoom lens system

a technology of zoom lens and zoom lens system, which is applied in the field of zoom lens system, imaging apparatus and method for zooming lens system, can solve the problems of insufficient satisfaction of high zoom ratio and inability to achieve excellent optical performance, and achieve excellent optical performance and high zoom ratio

Inactive Publication Date: 2011-08-11
NIKON CORP
View PDF16 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0004]The present invention is made in view of the aforementioned problems and has an object to provide a zoom lens system having excellent optical performance with a high zoom ratio, an imaging apparatus, and a method for zooming the zoom lens system.
[0013]The present invention makes it possible to provide a zoom lens system having a vibration reduction function with excellent optical performance capable of correcting an image blur on the image plane caused by a camera shake with keeping a high zoom ratio.

Problems solved by technology

However, conventional zoom lens system has a zoom ratio of about two, so that a requirement for a high zoom ratio cannot be sufficiently satisfied.
Moreover, since the position of an aperture stop is not optimized, excellent optical performance cannot be accomplished.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Zoom lens system, imaging apparatus, and method for zooming the zoom lens system
  • Zoom lens system, imaging apparatus, and method for zooming the zoom lens system
  • Zoom lens system, imaging apparatus, and method for zooming the zoom lens system

Examples

Experimental program
Comparison scheme
Effect test

first embodiment

[0063]A zoom lens system, an imaging apparatus, and a method for zooming the zoom lens system according to the first embodiment of the present application are explained.

[0064]The zoom lens system includes, in order from an object, a first lens group having negative refractive power, a second lens group having positive refractive power, a third lens group having negative refractive power, a fourth lens group having positive refractive power. An aperture stop is disposed between the second lens group and the fourth lens group. Upon zooming from a wide-angle end state to a telephoto end state, each lens group is moved such that a distance between the second lens group and the third lens group increases, and a distance between the third lens group and the fourth lens group decreases, and the aperture stop is moved together with the third lens group. The following conditional expressions (1) and (2) are satisfied:

1.20<f2 / fw<2.50   (1)

−2.10<f3 / fw<−0.80   (2)

where f2 denotes a ...

example 1

[0113]FIG. 1 is a sectional view showing a lens configuration of a zoom lens system according to Example 1 of a first embodiment in a wide-angle end state.

[0114]The zoom lens system according to Example 1 is composed of, in order from an object, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having negative refractive power, and a fourth lens group G4 having positive refractive power.

[0115]The first lens group G1 is composed of, in order from the object, a negative meniscus lens L11 having a convex surface facing the object, and a cemented lens constructed by a negative meniscus lens L12 having a convex surface facing the object cemented with a positive meniscus lens L13 having a convex surface facing the object. The negative meniscus lens L11 is an aspherical lens on which an aspherical surface is formed by forming a resin layer on the image side glass surface.

[0116]The second lens group G2 is c...

example 2

[0137]FIG. 5 is a sectional view showing a lens configuration of a zoom lens system according to Example 2 of the first embodiment in a wide-angle end state.

[0138]The zoom lens system according to Example 2 is composed of, in order from an object, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having negative refractive power, and a fourth lens group G4 having positive refractive power.

[0139]The first lens group G1 is composed of, in order from the object, a negative meniscus lens L11 having a convex surface facing the object, a double concave negative lens L12, and a positive meniscus lens L13 having a convex surface facing the object. The negative meniscus lens L11 is an aspherical lens on which an aspherical surface is formed by forming a resin layer on the image side glass surface.

[0140]The second lens group G2 is composed of, in order from the object, a cemented lens constructed by a negativ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

Providing a zoom lens system having excellent optical performance with a high zoom ratio, an imaging apparatus, and a method for zooming the zoom lens system. The system including, in order from an object, a first group G1 having negative refractive power, a second group G2 having positive refractive power, a third group G3 having negative refractive power, and a fourth group G4 having positive refractive power. An aperture stop S is disposed between the second group G2 and the fourth group G4. Upon zooming from a wide-angle end state to a telephoto end state, each group is moved such that a distance between the second group G2 and the third group G3 increases, a distance between the third group G3 and the fourth group G4 decreases, and the aperture stop S is moved together with the third group G3. Given conditions are satisfied.

Description

TECHNICAL FIELD [0001]The present invention relates to a zoom lens system, an imaging apparatus and a method for zooming the zoom lens system.BACKGROUND ART [0002]A zoom lens system suitable for a film camera, an electronic still camera, and a video camera has been proposed (for example, Japanese Patent Application Laid-Open Nos. 2004-61910, and 11-174329).[0003]However, conventional zoom lens system has a zoom ratio of about two, so that a requirement for a high zoom ratio cannot be sufficiently satisfied. Moreover, since the position of an aperture stop is not optimized, excellent optical performance cannot be accomplished.DISCLOSURE OF THE INVENTION [0004]The present invention is made in view of the aforementioned problems and has an object to provide a zoom lens system having excellent optical performance with a high zoom ratio, an imaging apparatus, and a method for zooming the zoom lens system.[0005]According to a first aspect of the present invention, there is provided a zoom...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(United States)
IPC IPC(8): G02B15/14
CPCG02B15/177G02B13/04G02B27/646G02B15/144511G02B13/18G02B15/14
Inventor SHIBATA, SATORUSUZUKI, TAKESHIYAMAMOTO, HIROSHI
Owner NIKON CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap