Patents by Inventor Keigo Koida

Keigo Koida has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20240061222
    Abstract: A zoom lens includes, in order from an object, a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a fourth lens group. Zooming is performed by changing respective distances between the first and second lens groups, the second and third lens groups, and the third and fourth lens groups. The first lens group includes a negative lens disposed closest to the object, and a negative lens. Specified conditional expressions are satisfied.
    Type: Application
    Filed: October 30, 2023
    Publication date: February 22, 2024
    Inventor: Keigo KOIDA
  • Patent number: 11822063
    Abstract: A zoom lens includes, in order from an object, a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a fourth lens group. Zooming is performed by changing respective distances between the first and second lens groups, the second and third lens groups, and the third and fourth lens groups. The first lens group includes a negative lens disposed closest to the object, and a negative lens. Specified conditional expressions are satisfied.
    Type: Grant
    Filed: July 1, 2021
    Date of Patent: November 21, 2023
    Assignee: Nikon Corporation
    Inventor: Keigo Koida
  • Publication number: 20230367109
    Abstract: A zoom optical system that can achieve size and weight reduction and has high optical performance, an optical apparatus, and a method for manufacturing the zoom optical system are provided. A zoom optical system GL used in an optical apparatus such as a camera 1 includes a first lens group G1 having positive refractive power and disposed closest to an object side, a second lens group G2, and a rear lens group GL, spaces between the lens groups change at zooming, the first lens group G1 includes a positive lens L11 closest to the object side, and the zoom optical system satisfies a condition expressed by an expression below, 0.30<D1MAX/G1d<0.70 in the expression, D1MAX: maximum air space on an optical axis in the first lens group G1, and G1d: thickness of the first lens group G1 on the optical axis.
    Type: Application
    Filed: December 2, 2021
    Publication date: November 16, 2023
    Inventor: Keigo KOIDA
  • Publication number: 20220334365
    Abstract: An optical system (LS) has an aperture stop (S), and a positive lens (L4) disposed closer to the object side than the aperture stop (S). The positive lens (L4) satisfies the following conditional expressions. ?0.010<ndP1?(2.015?0.0068×?dP1) 50.00<?dP1<65.00 0.545<?gFP1 ?0.010<?gFP1?(0.6418?0.00168×?dP1) where ndP1 is the refractive index to the d line of the positive lens, ?dP1 is the Abbe number with respect to the d line of the positive lens, and ?gFP1 is the partial dispersion ratio of the positive lens.
    Type: Application
    Filed: August 26, 2020
    Publication date: October 20, 2022
    Inventors: Masashi YAMASHITA, Tomoki ITO, Tomonori KURIBAYASHI, Keigo KOIDA, Satoshi MIWA, Yoko KOMATSUBARA, Katsuya WATANABE, Azuna NONAKA, Ayumu MAKIDA
  • Publication number: 20220291489
    Abstract: An optical system (LS) has an aperture stop (S), and a negative lens (L73) disposed closer to the image side than the aperture stop (S) and satisfying the following conditional expressions. ?0.010<ndN2?(2.015?0.0068×?dN2), 50.00<?dN2<65.00, 0.545<?gFN2, ?0.010<?gFN2?(0.6418?0.00168×?dN2) where ndN2 is the refractive index to the d line of the negative lens, ?dN2 is the Abbe number with respect to the d line of the negative lens, and ?gFN2 is the partial dispersion ratio of the negative lens.
    Type: Application
    Filed: August 26, 2020
    Publication date: September 15, 2022
    Inventors: Masashi YAMASHITA, Tomoki ITO, Tomonori KURIBAYASHI, Keigo KOIDA, Satoshi MIWA, Yoko KOMATSUBARA, Katsuya WATANABE, Azuna NONAKA, Ayumu MAKIDA
  • Publication number: 20220269055
    Abstract: An optical system (LS) has a lens (L11) that satisfies the following conditional expressions. ?0.010<ndLZ?(2.015?0.0068×?dLZ) 50.00<?dLZ<65.00 0.545<?gFLZ ?0.010<?gFLZ?(0.6418?0.00168×?dLZ) where ndLZ is the refractive index to the d line of the lens, ?dLZ is the Abbe number with respect to the d line of the lens, and ?gFLZ is the partial dispersion ratio of the lens.
    Type: Application
    Filed: August 26, 2020
    Publication date: August 25, 2022
    Inventors: Masashi YAMASHITA, Tomoki ITO, Tomonori KURIBAYASHI, Keigo KOIDA, Satoshi MIWA, Yoko KOMATSUBARA, Katsuya WATANABE, Azuna NONAKA, Ayumu MAKIDA
  • Publication number: 20220269056
    Abstract: This optical system (LS) has an aperture diaphragm (S) and a negative lens (L4) disposed closer to an object side than the aperture diaphragm (S) and satisfies the following conditional expression. ?0.010<ndN1?(2.015?0.0068×?dN1), 50.00<?dN1<65.00, 0.545<?gFN1, ?0.010<?gFN1?(0.6418?0.00168×?dN1). Where, ndN1 is a refractive index of the negative lens with respect to a d-line, vdN1 is an Abbe number of the negative lens based on the d-line, and ?gFN1 is a partial dispersion ratio of the negative lens.
    Type: Application
    Filed: August 26, 2020
    Publication date: August 25, 2022
    Inventors: Masashi YAMASHITA, Tomoki ITO, Tomonori KURIBAYASHI, Keigo KOIDA, Satoshi MIWA, Yoko KOMATSUBARA, Katsuya WATANABE, Azuna NONAKA, Ayumu MAKIDA
  • Publication number: 20210325645
    Abstract: A zoom lens includes, in order from an object, a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a fourth lens group. Zooming is performed by changing respective distances between the first and second lens groups, the second and third lens groups, and the third and fourth lens groups. The first lens group includes a negative lens disposed closest to the object, and a negative lens. Specified conditional expressions are satisfied.
    Type: Application
    Filed: July 1, 2021
    Publication date: October 21, 2021
    Inventor: Keigo KOIDA
  • Patent number: 11079574
    Abstract: A zoom lens consists of, in order from an object, a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a fourth lens group having a positive refractive power. Zooming is performed by changing respective distances between the first and second lens groups, the second and third lens groups, and the third and fourth lens groups. The first lens group consists of, in order from an object, a negative lens, a negative lens and a positive lens, the second lens group consists of five lenses, and the third lens group consists of a bi-concave negative lens.
    Type: Grant
    Filed: October 29, 2019
    Date of Patent: August 3, 2021
    Assignee: Nikon Corporation
    Inventor: Keigo Koida
  • Patent number: 11002948
    Abstract: A zoom lens comprises, 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 to satisfy the following conditional expression: 1.60<(?f1)/fw<2.50 where, f1 denotes a focal length of the first lens group; and fw denotes a focal length of the zoom lens as a whole in a wide-angle end state.
    Type: Grant
    Filed: December 9, 2016
    Date of Patent: May 11, 2021
    Assignee: Nikon Corporation
    Inventor: Keigo Koida
  • Publication number: 20200064605
    Abstract: A zoom lens consists of, in order from an object, a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a fourth lens group having a positive refractive power. Zooming is performed by changing respective distances between the first and second lens groups, the second and third lens groups, and the third and fourth lens groups. The first lens group consists of, in order from an object, a negative lens, a negative lens and a positive lens, the second lens group consists of five lenses, and the third lens group consists of a bi-concave negative lens.
    Type: Application
    Filed: October 29, 2019
    Publication date: February 27, 2020
    Inventor: Keigo KOIDA
  • Patent number: 10551601
    Abstract: A first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a fourth lens group having a positive refractive power are provided in order from an object. The first to fourth lens groups move on an optical axis so that zooming is performed by changing each distance between adjacent lens groups. The first lens group comprises, in order from the object, a negative lens arranged closest to the object, a negative lens and a positive lens, and when an air interval between the third and fourth lens groups in the wide-angle end state is denoted as D3T and an air interval between the third and fourth lens groups in the telephoto end state is denoted as D3T, the following condition is satisfied: 0.30<D3W/D3T<1.10.
    Type: Grant
    Filed: May 21, 2016
    Date of Patent: February 4, 2020
    Assignee: Nikon Corporation
    Inventor: Keigo Koida
  • Patent number: 10481370
    Abstract: An optical system has, in order from an object: a first lens having negative refractive power; a second lens having positive refractive power; a third lens having positive refractive power; a fourth lens having negative refractive power; a fifth lens having negative refractive power; and a sixth lens having positive refractive power, wherein the following conditional expression (1) is satisfied: 1.52<L3R1/f3 - - - (1), where L3R1 denotes a radius of curvature of an object side lens surface of the third lens L3, and f3 denotes a focal length of the third lens L3.
    Type: Grant
    Filed: February 13, 2014
    Date of Patent: November 19, 2019
    Assignee: Nikon Corporation
    Inventors: Keigo Koida, Atsushi Suzuki
  • Publication number: 20190064492
    Abstract: A zoom lens comprises, 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 to satisfy the following conditional expression: 1.60<(?f1)/fw<2.50 where, f1 denotes a focal length of the first lens group; and fw denotes a focal length of the zoom lens as a whole in a wide-angle end state.
    Type: Application
    Filed: December 9, 2016
    Publication date: February 28, 2019
    Inventor: Keigo KOIDA
  • Patent number: 9671586
    Abstract: Provided is an optical system having, in order from an object, a positive first lens group (G1), an aperture stop (S) and a second lens group (G2), wherein the first lens group (G1) includes, in order from the object, a negative lens component (L1), a positive lens component (L2) and a first lens component (L3, L4), the image side surface of which is a concave surface facing the aperture stop (S), the second lens group (G2) includes, in order from the object, a second lens component (L5, L6), the object side surface of which is a concave surface facing the aperture stop (S), and a positive lens component (L8) disposed closest to the image, the first lens component (L1) and the second lens component (L2) face each other sandwiching the aperture stop (S), and the following conditional expressions (1) and (2) are satisfied: 1.5<fG1/f<2.6 . . . (1) and 2.1<TL/f<3.1 . . .
    Type: Grant
    Filed: February 20, 2013
    Date of Patent: June 6, 2017
    Assignee: Nikon Corporation
    Inventor: Keigo Koida
  • Publication number: 20160341939
    Abstract: A first lens group (G1) having a negative refractive power, a second lens group (G2) having a positive refractive power, a third lens group (G3) having a negative refractive power, and a fourth lens group (G4) having a positive refractive power are provided in order from an object, and the first lens group (G1), the second lens group (G2), the third lens group (G3), and the fourth lens group (G4) move on an optical axis so that zooming is performed by changing distances between each lens group, and the first lens group (G1) comprises, in order from the object, a negative lens (L11) arranged closest to the object, a negative lens and a positive lens, and when an air interval between the third lens group (G3) and the fourth lens group (G4) in the wide-angle end state is denoted as D3T and an air interval between the third lens group (G3) and the forth lens group (G4) in the telephoto end state is denoted as D3T, and the following condition (1) is satisfied: 0.30<D3W/D3T<1.10.
    Type: Application
    Filed: May 21, 2016
    Publication date: November 24, 2016
    Inventor: Keigo KOIDA
  • Publication number: 20150241666
    Abstract: An optical system has, in order from an object: a first lens having negative refractive power; a second lens having positive refractive power; a third lens having positive refractive power; a fourth lens having negative refractive power; a fifth lens having negative refractive power; and a sixth lens having positive refractive power, wherein the following conditional expression (1) is satisfied: 1.52<L3R1/f3 - - - (1), where L3R1 denotes a radius of curvature of an object side lens surface of the third lens L3, and f3 denotes a focal length of the third lens L3.
    Type: Application
    Filed: February 13, 2014
    Publication date: August 27, 2015
    Inventors: Keigo Koida, Atsushi Suzuki
  • Publication number: 20150226936
    Abstract: The present invention has, in order from an object: a first lens (L1) having negative refractive power; a second lens (L2), which is a positive meniscus lens having a convex surface facing the object; an aperture stop (S); and a third lens (L3) having a convex surface facing the object, and satisfies the following conditional expression (1): 6.6<|f12/f|??(1) where f12 denotes a composite focal length of the first lens (L1) and the second lens (L2), and f denotes a focal length of the optical system (WL).
    Type: Application
    Filed: February 14, 2014
    Publication date: August 13, 2015
    Applicant: Nikon Corporation
    Inventors: Atsushi Suzuki, Keigo Koida
  • Publication number: 20150098134
    Abstract: Provided is an optical system having, in order from an object, a positive first lens group (G1), an aperture stop (S) and a second lens group (G2), wherein the first lens group (G1) includes, in order from the object, a negative lens component (L1), a positive lens component (L2) and a first lens component (L3, L4), the image side surface of which is a concave surface facing the aperture stop (S), the second lens group (G2) includes, in order from the object, a second lens component (L5, L6), the object side surface of which is a concave surface facing the aperture stop (S), and a positive lens component (L8) disposed closest to the image, the first lens component (L1) and the second lens component (L2) face each other sandwiching the aperture stop (S), and the following conditional expressions (1) and (2) are satisfied: 1.5<fG1/f<2.6 . . . (1) and 2.1<TL/f<3.1 . . .
    Type: Application
    Filed: February 20, 2013
    Publication date: April 9, 2015
    Inventor: Keigo Koida