弯月透镜与其它透镜组合可加长或缩短原有透镜的焦距，在系统中不增加球差或慧差。弯月透镜分为正弯月透镜和负弯月透镜：
正弯月（凸）透镜设计用于最小化球差。与另一透镜结合使用时，正弯月透镜可以减小焦距，从而在不引入明显球面像差的情况下，增加系统数值孔径(NA)。当用于会聚平行光时，透镜的凸面应朝向光源，以使球差最小化。
| 材料 | H-K9L、紫外熔石英、H-ZF13、CaF2、蓝宝石 .etc. |
| 尺寸公差 | ±0.2(标准精度). ±0.05(高精度) |
| 厚度公差 | ±0.2mm |
| 设计波长 | 546.1nm |
| 表面质量 | 60/40 |
| 面型 | λ/4@633nm（标准精度), λ/10@633nm(高精度) |
| 偏心度 | <3分 |
| 焦距公差 | ±2% |
| 通光孔径 | >90% |
| 倒角 | 保护性<0.5mmx45° |
| 镀膜 | 无,AR,PR, HR, etc. |
| 型号 | 材料 | 直径(mm) | 焦距(mm) | R1(mm) | R2(mm) | 中心厚(mm) | 边厚(mm) | 后焦距(mm) |
| MEND25.4F50 | H-K9L | 25.4 | 50 | 20.58 | 90 | 6 | 2.5 | 45 |
| MEND25.4F100 | H-K9L | 25.4 | 100 | 32.1 | 82.2 | 3.6 | 2 | 95.9 |
| MEND25.4F125 | H-K9L | 25.4 | 125 | 40.6 | 106.9 | 3.3 | 2 | 121.2 |
| MEND25.4F150 | H-K9L | 25.4 | 150 | 49.1 | 131.6 | 3.1 | 2 | 146.3 |
| MEND25.4F200 | H-K9L | 25.4 | 200 | 66.2 | 182.2 | 2.8 | 2 | 196.5 |
| MEND25.4F300 | H-K9L | 25.4 | 300 | 100.9 | 288.2 | 2.5 | 2 | 296.5 |
| MEND25.4F500 | H-K9L | 25.4 | 500 | 123.9 | 235 | 3.5 | 3.2 | 495.4 |
| MEND50.8F100 | H-K9L | 50.8 | 100 | 30.3 | 65.8 | 9.7 | 1.1 | 88.8 |
| MEND50.8F150 | H-K9L | 50.8 | 150 | 47.9 | 119.3 | 7.3 | 2.7 | 141.7 |
| MEND50.8F200 | H-K9L | 50.8 | 200 | 65.2 | 171.6 | 6.2 | 2.9 | 192.9 |
| MEND50.8F250 | H-K9L | 50.8 | 250 | 82.5 | 224.7 | 5.5 | 2.9 | 243.5 |
| MEND50.8F300 | H-K9L | 50.8 | 300 | 100.1 | 279.1 | 5.1 | 3 | 293.8 |
| MEND25.4F-50 | H-K9L | 25.4 | -50 | 90 | 19.9 | 3 | 6.7 | -49.5 |
| MEND25.4F-100 | H-K9L | 25.4 | -100 | 90 | 32.59 | 3 | 4.5 | -99.2 |
| MEND25.4F-150 | H-K9L | 25.4 | -150 | 100 | 43.1 | 3 | 4.1 | -148 |
| MEND25.4F-200 | H-K9L | 25.4 | -200 | 100 | 50.2 | 3 | 3.8 | -197.3 |
| MEND25.4F-300 | H-K9L | 25.4 | -300 | 250 | 95.1 | 3 | 3.5 | -297.8 |
| MEND25.4F-400 | H-K9L | 25.4 | -400 | 250 | 112.5 | 3 | 3.4 | -397 |
| MEND25.4F-500 | H-K9L | 25.4 | -500 | 250 | 126.3 | 3 | 3.3 | -496.3 |
| MEND25.4F-1000 | H-K9L | 25.4 | -1000 | 500 | 253.2 | 3 | 3.2 | -994.6 |
