摘要 |
An objective lens system having a first and a second lens group that are separated by a gap where a ray bundle between the first and second lens is substantially telecentric and the second lens group has two lens elements that are also separated by a gap. The first lens element in the second lens group is a positive optical power lens and the second lens element in the second lens group is a negative optical power lens. The objective lens system has a relatively small number of lens elements and the aberration, including chromatic, spherical, coma, astigmatic difference, and distortion, are favorably corrected. In one embodiment, the objective lens system is used in a plan-achromatic microscope objective lens having a numerical aperture of 1.25 to 1.30 with a Petzval sum of 0.1. In a second embodiment, the objective lens system with is used in an achromat microscope objective lens with improved resolution and a greater than 50% transmittance of light at a wavelength of 340 nanometers.
|