| 摘要 |
A mid-infrared objective lens assembly (10) includes a plurality of spaced apart, refractive lens elements (20) that operate in the mid-infrared spectral range, the plurality of lens elements (20) including an aplanatic first lens element (26) that is closest to an object (14) to be observed. The first lens element (26) has a forward surface (36) that faces the object (14) and a rearward surface (38) that faces away from the object (14). The forward surface (36) can have a radius of curvature that is negative. |
