Objective lens system for microscopes
OwnerJihei Nakagawainventor
Life of this patent
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Abstract
An apochromat type high magnification objective lens system for microscopes comprising a first cemented semispherical lens component, a second positive meniscus lens component, a third cemented lens component consisting of three lens elements, a fourth cemented lens component consisting of three lens elements, a fifth cemented meniscus lens component and sixth cemented meniscus lens component. Said lens system is so designed as to assure favorably corrected aberrations by improving the fourth, fifth and sixth lens components so as to have enhanced functions to correct chromatic aberration and other aberrations.
Claims3
An objective lens system for microscopes comprising a first semispherical lens component having an embedded semispherical lens element, a second positive meniscus lens component having a concave surface on the object side, a third cemented lens component consisting of a positive element, a negative element and a positive element, a fourth cemented lens component consisting of a negative element, a positive element and a negative element, a fifth cemented meniscus lens component having a convex surface on the object side, and a sixth cemented meniscus lens component having a convex surface on the object side and arranged with a relatively wide airspace from said fifth lens component, and said lens system satisfying the following conditions:
- -80f<f.sub.4 <f.sub.5 <f.sub.6 <-29 (1)
- 13f>.vertline.f.sub.456 .vertline.>11f, f.sub.456 <0 (2)
- 5.5f>d.sub.16 >5f (3)
- .nu..sub.12 =2.57,.nu..sub.13 =66.8 (4)
- wherein the reference symbols f.sub.4, f.sub.5 and f.sub.6 represent focal lengths of the fourth, fifth and sixth lens components respectively, the reference symbol f.sub.456 designates total focal length of the fourth, fifth and sixth lens components considered as an assembly, the reference symbol f denotes focal length of said lens system as a whole, the reference symbol d.sub.16 represents air space formed between the fifth and sixth lens components, and the reference symbols .nu..sub.12 and .nu..sub.13 designate Abbe's numbers of the two elements of the sixth lens components.
Dependencies are inferred from the claim text.