| 摘要 |
The present invention offers a dry-type microscope objective lens which has a high NA in the range from low magnification to middle magnification and is lightweight and by which a high-resolution image can be obtained without taking a user time and trouble in observation. A dry-type microscope objective lens according to the present invention comprises, in order from the object side, a first lens group, a second lens group, and a third lens group, the first lens group comprises a meniscus lens which is arranged on the most object side and which turns its concave surface to the object side and the first lens group has positive refracting power as a whole, the second lens group comprises plural cemented lens units and has positive refracting power as a whole, the third lens group comprises air contact surfaces which are concave surfaces adjoining each other and facing toward each other and the third lens group has negative refracting power as a whole, and the dry-type microscope objective lens satisfies the following conditions: 6≦̸D/f≦̸8 5≦̸f 0.8≦̸NA<1.0 where D is a distance from an object surface to the last surface of the objective lens, f is a focal length of the objective lens, and NA is an object-side numerical aperture.
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