K9材料的窗口在330nm-2100nm 的波段范围内有较高的透过率， 该窗口镀上增透膜后，透过率可以在99.5%以上。
产品参数：
材料：K9
尺寸容差：+0.0/-0.15mm
表面精度：λ/4 @632.8nm
光洁度：40-20
中心偏差：<3 arc min
通光孔径：>90%
倒边：0.25mm×45°
| 型号 | 直径D(mm) | 厚度T(mm) |
| LOWB6-2 | 6.00 | 2.00 |
| LOWB10-3 | 10.00 | 3.00 |
| LOWB12.7-3 | 12.70 | 3.00 |
| LOWB12.7-5 | 12.70 | 5.00 |
| LOWB15-3 | 15.00 | 3.00 |
| LOWB15-5 | 15.00 | 5.00 |
| LOWB20-3 | 20.00 | 3.00 |
| LOWB20-5 | 20.00 | 5.00 |
| LOWB25.4-3 | 25.40 | 3.00 |
| LOWB25.4-5 | 25.40 | 5.00 |
| LOWB30-3 | 30.00 | 3.00 |
| LOWB30-5 | 30.00 | 5.00 |
| LOWB38.1-3 | 38.10 | 3.00 |
| LOWB38.1-5 | 38.10 | 5.00 |
| LOWB40-5 | 40.00 | 5.00 |
| LOWB40-8 | 40.00 | 8.00 |
| LOWB50.8-5 | 50.80 | 5.00 |
| LOWB50.8-8 | 50.80 | 8.00 |
| LOWB75-5 | 75.00 | 5.00 |
| LOWB75-10 | 75.00 | 10.00 |
| LOWB100-10 | 100.00 | 10.00 |
| LOWB100-12 | 100.00 | 12.00 |
| LOWB150-20 | 150.00 | 20.00 |
| LOWBS4-2 | 4.00*4.00 | 2.00 |
| LOWBS5-2 | 5.00*5.00 | 2.00 |
| LOWBS6-3 | 6.00*6.00 | 3.00 |
| LOWBS12.7-3 | 12.70*12.70 | 3.00 |
| LOWBS15-3 | 15.00*15.00 | 3.00 |
| LOWBS20-3 | 20.00*20.00 | 3.00 |
| LOWBS25.4-3 | 25.40*25.40 | 3.00 |
| LOWBS30-5 | 30.00*30.00 | 5.00 |
| LOWBS38.1-5 | 38.10*38.10 | 5.00 |
| LOWBS40-5 | 40.00*40.00 | 5.00 |
| LOWBS50.8-8 | 50.80*50.80 | 8.00 |
| LOWBS75-8 | 75.00*75.00 | 8.00 |
| LOWBS100-12 | 100.00*100.00 | 12.00 |
