Immersion microscope objective
An immersion microscope objective includes: a first lens group that includes a meniscus lens component that is closest to an image among the components of the first lens group, the meniscus lens component having a convex surface facing an object; and a second lens group that includes at least one lens component. The first lens group includes a first cemented lens that is closest to the object. The first cemented lens consists of a planoconvex lens that includes a plane surface facing the object and a meniscus lens that has a negative refractive power. The objective satisfies the following conditional expressions: 2.4≤ f 1/ fob (1) 1.8≤ n 12≤1.85 (2) where f1 indicates a focal length that the first cemented lens has for an e line, fob indicates a focal length that the objective has for the e line, and n12 indicates a refractive index that the meniscus lens has for the e line.
1. An immersion microscope objective comprising:
a first lens group that includes a meniscus lens component that is closest to an image among components of the first lens group, the meniscus lens component having a convex surface facing an object; and
a second lens group that is closer to the image than the first lens group is and includes at least one lens component,
wherein:
the first lens group includes a first cemented lens that is closest to the object among the components of the first lens group,
the first cemented lens consists of a planoconvex lens that includes a plane surface facing the object and a meniscus lens that has a negative refractive power and includes a concave surface facing the object, wherein the object, the planoconvex lens, and the meniscus lens are arranged in this order, and
the immersion microscope objective satisfies the following conditional expressions:
2.4≤ f 1/ fob (1)
1.8≤ n 12≤1.85 (2)
1.4≤ NA ob (8)
−2≤Δ z1 /DOF e 2 (9)
where f1 indicates a focal length that the first cemented lens has for an e line, fob indicates a focal length that the immersion microscope objective has for the e line, n12 indicates a refractive index that the meniscus lens has for the e line, NA ob indicates a numerical aperture on an object side of the immersion microscope objective, Δz 1 indicates a difference between a position on an optical axis at which an RMS wave aberration in an h line is minimized and a position on the optical axis at which an RMS wave aberration in the e line is minimized, and DOF e indicates a depth of focus for the e line.
2. The immersion microscope objective of claim 1 , satisfying the following conditional expression:
0.095≤ d 12/ L total (3)
where d12 indicates a thickness that the meniscus lens has on the optical axis, and L total indicates a distance on the optical axis from an object surface to a lens surface that is closest to the image among lens surfaces of the immersion microscope objective.
3. The immersion microscope objective of claim 2 , wherein:
the first lens group further includes a biconvex lens,
the biconvex lens is included in a lens component that is closest, second closest, or third closest to the object among components of the immersion microscope objective, and
the immersion microscope objective satisfies the following conditional expression:
0.014≤ NA ob |β|≤0.034 (4)
where β indicates a magnification of the immersion microscope objective.
4. The immersion microscope objective of claim 3 , satisfying the following conditional expression:
1.4≤ n 13≤1.85 (5)
where n13 indicates a refractive index that the biconvex lens has for the e line.
5. The immersion microscope objective of claim 4 , satisfying the following conditional expression:
0≤| R 1|/| R 2|≤1 (6)
where R1 indicates a radius of curvature of a lens surface on an object side of the biconvex lens, and R2 indicates a radius of curvature of a lens surface on an image side of the biconvex lens.
6. The immersion microscope objective of claim 4 , satisfying the following conditional expressions:
0.014≤ NA ob |β|≤0.034 (4)
P ob ≤0 (7)
where β indicates a magnification of the immersion microscope objective, and P ob indicates a Petzval sum of the immersion microscope objective for the e line.
7. The immersion microscope objective of claim 3 , satisfying the following conditional expression:
0≤| R 1|/| R 2|≤1 (6)
where R1 indicates a radius of curvature of a lens surface on an object side of the biconvex lens, and R2 indicates a radius of curvature of a lens surface on an image side of the biconvex lens.
8. The immersion microscope objective of claim 3 , satisfying the following conditional expressions:
0.014≤ NA ob |β|≤0.034 (4)
P ob ≤0 (7)
where β indicates a magnification of the immersion microscope objective, and P ob indicates a Petzval sum of the immersion microscope objective for the e line.
9. The immersion microscope objective of claim 2 , satisfying the following conditional expressions:
0.014≤ NA ob |β|≤0.034 (4)
P ob ≤0 (7)
where β indicates a magnification of the immersion microscope objective, and P ob indicates a Petzval sum of the immersion microscope objective for the e line.
10. The immersion microscope objective of claim 1 , wherein:
the first lens group further includes a biconvex lens,
the biconvex lens is included in a lens component that is closest, second closest, or third closest to the object among components of the immersion microscope objective, and
the immersion microscope objective satisfies the following conditional expression:
0.014≤ NA ob |β|≤0.034 (4)
where β indicates a magnification of the immersion microscope objective.
11. The immersion microscope objective of claim 10 , satisfying the following conditional expression:
1.4≤ n 13≤1.85 (5)
where n13 indicates a refractive index that the biconvex lens has for the e line.
12. The immersion microscope objective of claim 11 , satisfying the following conditional expression:
0≤| R 1|/| R 2|≤1 (6)
where R1 indicates a radius of curvature of a lens surface on an object side of the biconvex lens, and R2 indicates a radius of curvature of a lens surface on an image side of the biconvex lens.
13. The immersion microscope objective of claim 11 , satisfying the following conditional expressions:
0.014≤ NA ob |β|≤0.034 (4)
P ob ≤0 (7)
where β indicates a magnification of the immersion microscope objective, and P ob indicates a Petzval sum of the immersion microscope objective for the e line.
14. The immersion microscope objective of claim 10 , satisfying the following conditional expression:
0≤| R 1|/| R 2|≤1 (6)
where R1 indicates a radius of curvature of a lens surface on an object side of the biconvex lens, and R2 indicates a radius of curvature of a lens surface on an image side of the biconvex lens.
15. The immersion microscope objective of claim 14 , satisfying the following conditional expressions:
0.014≤ NA ob |β|≤0.034 (4)
P ob ≤0 (7)
where β indicates a magnification of the immersion microscope objective, and P ob indicates a Petzval sum of the immersion microscope objective for the e line.
16. The immersion microscope objective of claim 10 , satisfying the following conditional expressions:
0.014≤ NA ob |β|≤0.034 (4)
P ob ≤0 (7)
where β indicates a magnification of the immersion microscope objective, and P ob indicates a Petzval sum of the immersion microscope objective for the e line.
17. The immersion microscope objective of claim 1 , satisfying the following conditional expressions:
0.014≤ NA ob |β|≤0.034 (4)
P ob ≤0 (7)
where β indicates a magnification of the immersion microscope objective, and P ob indicates a Petzval sum of the immersion microscope objective for the e line.
18. The immersion microscope objective of claim 1 , satisfying the following conditional expression:
9 mm≤ Y reso ×|β|≤20 mm (10)
where Y reso indicates a maximum object height within a region on a plane orthogonal to the optical axis that crosses the position on the optical axis at which the RMS wave aberration in the e line is minimized, the region being such that the RMS wave aberration in the e line is 0.2λ e or lower, λ e indicates a wavelength of the e line, and β indicates a magnification of the immersion microscope objective.
19. The immersion microscope objective of claim 1 , satisfying the following conditional expression:
L total ≤100 mm (11)
where L total indicates a distance on the optical axis from an object surface to a lens surface that is closest to the image among lens surfaces of the immersion microscope objective.
20. An immersion microscope objective comprising:
a first lens group that includes a meniscus lens component that is closest to an image among components of the first lens group, the meniscus lens component having a convex surface facing an object; and
a second lens group that is closer to the image than the first lens group is and includes at least one lens component,
wherein:
the first lens group includes a first cemented lens that is closest to the object among the components of the first lens group,
the first cemented lens consists of a planoconvex lens that includes a plane surface facing the object and a meniscus lens that has a negative refractive power and includes a concave surface facing the object, wherein the object, the planoconvex lens, and the meniscus lens are arranged in this order, and
the immersion microscope objective satisfies the following conditional expressions:
2.4≤ f 1/ fob (1)
1.8≤ n 12≤1.85 (2)
9 mm≤ Y reso ×|β|≤20 mm (10)
where f1 indicates a focal length that the first cemented lens has for an e line, fob indicates a focal length that the immersion microscope objective has for the e line, n12 indicates a refractive index that the meniscus lens has for the e line, Y reso indicates a maximum object height within a region on a plane orthogonal to an optical axis that crosses a position on the optical axis at which an RMS wave aberration in the e line is minimized, the region being such that the RMS wave aberration in the e line is 0.2λ e or lower, λ e indicates a wavelength of the e line, and β indicates a magnification of the immersion microscope objective.
21. The immersion microscope objective of claim 20 , satisfying the following conditional expression:
0.095≤ d 12/ L total (3)
where d12 indicates a thickness that the meniscus lens has on the optical axis, and L total indicates a distance on the optical axis from an object surface to a lens surface that is closest to the image among lens surfaces of the immersion microscope objective.
22. The immersion microscope objective of claim 21 , wherein:
the first lens group further includes a biconvex lens,
the biconvex lens is included in a lens component that is closest, second closest, or third closest to the object among components of the immersion microscope objective, and
the immersion microscope objective satisfies the following conditional expression:
0.014≤ NA ob |β|≤0.034 (4)
where NA ob indicates a numerical aperture on an object side of the immersion microscope objective.
23. The immersion microscope objective of claim 22 , satisfying the following conditional expression:
1.4≤ n 13≤1.85 (5)
where n13 indicates a refractive index that the biconvex lens has for the e line.
24. The immersion microscope objective of claim 23 , satisfying the following conditional expression:
0≤| R 1|/| R 2|≤1 (6)
where R1 indicates a radius of curvature of a lens surface on an object side of the biconvex lens, and R2 indicates a radius of curvature of a lens surface on an image side of the biconvex lens.
25. The immersion microscope objective of claim 23 , satisfying the following conditional expressions:
0.014≤ NA ob |β|≤0.034 (4)
P ob ≤0 (7)
where NA ob indicates a numerical aperture on an object side of the immersion microscope objective, and P ob indicates a Petzval sum of the immersion microscope objective for the e line.
26. The immersion microscope objective of claim 22 , satisfying the following conditional expression:
0≤| R 1|/| R 2|≤1 (6)
where R1 indicates a radius of curvature of a lens surface on an object side of the biconvex lens, and R2 indicates a radius of curvature of a lens surface on an image side of the biconvex lens.
27. The immersion microscope objective of claim 22 , satisfying the following conditional expression:
0.014≤ NA ob |β|≤0.034 (4)
P ob ≤0 (7)
where NA ob indicates a numerical aperture on an object side of the immersion microscope objective, and P ob indicates a Petzval sum of the immersion microscope objective for the e line.
28. The immersion microscope objective of claim 21 , satisfying the following conditional expressions:
0.014≤ NA ob |β|≤0.034 (4)
P ob ≤0 (7)
where NA ob indicates a numerical aperture on an object side of the immersion microscope objective, and P ob indicates a Petzval sum of the immersion microscope objective for the e line.
29. The immersion microscope objective of claim 20 , wherein:
the first lens group further includes a biconvex lens,
the biconvex lens is included in a lens component that is closest, second closest, or third closest to the object among components of the immersion microscope objective, and
the immersion microscope objective satisfies the following conditional expression:
0.014≤ NA ob |β|≤0.034 (4)
where NA ob indicates a numerical aperture on an object side of the immersion microscope objective.
30. The immersion microscope objective of claim 29 , satisfying the following conditional expression:
1.4≤ n 13≤1.85 (5)
where n13 indicates a refractive index that the biconvex lens has for the e line.
31. The immersion microscope objective of claim 30 , satisfying the following conditional expression:
0≤| R 1|/| R 2|≤1 (6)
where R1 indicates a radius of curvature of a lens surface on an object side of the biconvex lens, and R2 indicates a radius of curvature of a lens surface on an image side of the biconvex lens.
32. The immersion microscope objective of claim 30 , satisfying the following conditional expressions:
0.014≤ NA ob |β|≤0.034 (4)
P ob ≤0 (7)
where NA ob indicates a numerical aperture on an object side of the immersion microscope objective, and P ob indicates a Petzval sum of the immersion microscope objective for the e line.
33. The immersion microscope objective of claim 29 , satisfying the following conditional expression:
0≤| R 1|/| R 2|≤1 (6)
where R1 indicates a radius of curvature of a lens surface on an object side of the biconvex lens, and R2 indicates a radius of curvature of a lens surface on an image side of the biconvex lens.
34. The immersion microscope objective of claim 33 , satisfying the following conditional expressions:
0.014≤ NA ob |β|≤0.034 (4)
P ob ≤0 (7)
where NA ob indicates a numerical aperture on an object side of the immersion microscope objective, and P ob indicates a Petzval sum of the immersion microscope objective for the e line.
35. The immersion microscope objective of claim 29 , satisfying the following conditional expression:
P ob ≤0 (7)
where P ob indicates a Petzval sum of the immersion microscope objective for the e line.
36. The immersion microscope objective of claim 20 , satisfying the following conditional expressions:
0.014≤ NA ob |β|≤0.034 (4)
P ob ≤0 (7)
where NA ob indicates a numerical aperture on an object side of the immersion microscope objective, and P ob indicates a Petzval sum of the immersion microscope objective for the e line.
37. The immersion microscope objective of claim 20 , satisfying the following conditional expression:
L total ≤100 mm (11)
where L total indicates a distance on the optical axis from an object surface to a lens surface that is closest to the image among lens surfaces of the immersion microscope objective.