Title:
LENS SYSTEM AND IMAGING DEVICE
Document Type and Number:
WIPO Patent Application WO/2019/244867
Kind Code:
A1
Abstract:
An imaging lens system (10) is provided. Arranged in order from the object side (11), this imaging lens system (10) is configured from a negative refractive power first lens group (G1), a positive refractive power second lens group (G2), a positive refractive power third lens group (G3), an aperture (St), and a positive refractive power fourth lens group (G4). The third lens group (G3) includes, furthest on the image side (12), a cemented lens (B2) which is arranged on the object side (11) of the aperture (St) and the surface on the image side (12) of which includes a surface that is concave towards the object side (11). The fourth lens group (G4) includes, furthest on the object side (11), a cemented lens (B3) which is arranged on the image side (12) of the aperture (St), and the object-side surface of which includes a surface that is concave towards the image side. The radius of curvature g3er of the surface concave towards the object side and the radius of curvature g4fr of the surface concave towards the image side satisfy the following condition.
2.5 ≤ |g4fr/g3er| ≤ 4.0
Inventors:
MIYASHITA YUYA (JP)
Application Number:
PCT/JP2019/024031
Publication Date:
December 26, 2019
Filing Date:
June 18, 2019
Export Citation:
Assignee:
NITTOH INC (JP)
International Classes:
G02B13/00; G02B13/18
Domestic Patent References:
| WO2015072245A1 | 2015-05-21 |
Foreign References:
| JP2004061679A | 2004-02-26 | |||
| US20140002910A1 | 2014-01-02 | |||
| JP2012053260A | 2012-03-15 |
Other References:
See also references of EP 3812820A4
Attorney, Agent or Firm:
IMAI, Akira (JP)
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