| CPC G01J 3/0208 (2013.01) [G02B 21/04 (2013.01)] | 20 Claims |

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1. An objective lens system, comprising:
a primary aspheric mirror having a first R-value; and
a secondary aspheric mirror having a second R-value smaller than the first R-value, wherein the primary and secondary aspheric mirrors form a Schwarzchild structure having a working distance of at least 20 mm and a numerical aperture of 0.29-0.65, and wherein surfaces of the primary and secondary aspheric mirrors are defined by a series of aspheric parameters including a non-zero sixth order aspheric parameter.
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