Design of a novel eyepiece for low-level-light night-vision system

To resolve the contradictions between high performance, low distortion and lightweight ,a novel eyepiece with freeform surface and diffractive surface was presented. Based on the conventional erfle eyepiece, a noel eyepiece with freeform surface and diffractive surface was designed by Zemax software. The noel eyepiece system consisted of three lenses. Only glass K9 was used in the noel eyepiece system. The optical performance of the noel eyepiece were compared with the erfle eyepiece. It is shown that the novel eyepiece not only has better performanc, as transverse aberration, lateral color, distortion and field curvature, but also has greatly improved in weight and total length, which can meet the demands of night vision eyepiece system. It also provide a new approach for lightweight and compact low-level-light night- vision eyepiece system system designs.