Title:
ZOOM LENS AND IMAGING DEVICE PROVIDED THEREWITH
Document Type and Number:
WIPO Patent Application WO/2019/142761
Kind Code:
A1
Abstract:
In order to achieve a zoom lens with chromatic aberration sufficiently corrected in the wavelength region from visible light to near infrared light while maintaining compactness and a high zoom ratio, this zoom lens includes, arranged in order from the object side towards the image side, a first through a third lens groups which are positive, negative and positive, and a rear group which includes at least one lens group, wherein the first lens group has at least two negative lenses and at least two positive lenses, the zoom lens has an aperture stop and a lens group which is arranged on the image side of the aperture stop and which moves during zoom, and wherein the following are configured appropriately: the average partial dispersion ratio and average Abbe number of the two negative lenses of the at least two negative lenses that have the highest refractive power, the average partial dispersion ratio and average Abbe number of the two positive lenses of the at least two positive lenses that have the highest refractive power, the larger Abbe number of the Abbe numbers of the two negative lenses, the smaller Abbe number of the Abbe numbers of the two positive lenses, and the focal distances of the first and second lens groups.
Inventors:
EGUCHI YOSUKE (JP)
Application Number:
PCT/JP2019/000853
Publication Date:
July 25, 2019
Filing Date:
January 15, 2019
Export Citation:
Assignee:
CANON KK (JP)
International Classes:
G02B15/20; G02B13/18
Domestic Patent References:
| WO2010098407A1 | 2010-09-02 |
Foreign References:
| JP2009042563A | 2009-02-26 | |||
| JP2016080975A | 2016-05-16 | |||
| JP2017026974A | 2017-02-02 | |||
| JP2004240398A | 2004-08-26 | |||
| JP2000105336A | 2000-04-11 | |||
| JP2018155818A | 2018-10-04 | |||
| JP2018189839A | 2018-11-29 |
Attorney, Agent or Firm:
OKABE Yuzuru et al. (JP)
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