Title:
液浸系対物レンズ
Document Type and Number:
Japanese Patent JP6906923
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide an immersion objective lens having a high numerical aperture of 1.42 or greater and achieving an apochromat.SOLUTION: An objective lens 1 is an immersion objective lens having a numerical aperture of 1.42 or greater, and comprises in order from an object side: a positive first lens group G1; a positive second lens group G2; and a negative third lens group G3. The first lens group G1 is composed of: a first cemented lens CL1 including a plano-convex lens L1 and a first meniscus lens L2 whose concave surface faces the object side; and a positive lens L3. The second lens group G2 includes a plurality of cemented lens. The third lens group G3 includes in order from the object side: a cemented lens CL4 that has a positive lens L11 and a negative lens L12 and whose concave face faces an image side; a negative lens L13 whose concave surface faces the object side; and a positive lens L14. The objective lens satisfies the following conditional expression: 3.5≤(H/f)×NA≤5.2 (1), when H represents a maximum value of the height of on-axis marginal rays, f represents a focal length, and NArepresents a numerical aperture.SELECTED DRAWING: Figure 1
Inventors:
Koichi Konishi
Application Number:
JP2016206388A
Publication Date:
July 21, 2021
Filing Date:
October 20, 2016
Export Citation:
Assignee:
Olympus Endo Technology America Inc.
International Classes:
G02B21/02
Domestic Patent References:
| JP2006113486A | ||||
| JP2007121338A | ||||
| JP7281097A |
Attorney, Agent or Firm:
Hiroyoshi Aoki
Amada Masayuki
Yoshiyuki Osuga
Naoki Yano
Amada Masayuki
Yoshiyuki Osuga
Naoki Yano