Borosilicate glass is made by using the characteristics of conducting electricity of glass under hig...
K9(BK7) has excellent mechanical properties and very low bubble K9(b270) product drawing and impurities, with good scratch resistance. Because of its stable chemical properties, no special treatment grinding and polishing. It is applied in many fields such as photoelectron, microwave technology, diffraction optical element and so on.
| Properties | Note |
| Transmission range | 0.4μm to 2.5μm |
| Density | 2.51 g/cc |
| Thermal expansion | 7.1×10 - 6/°F @ - 30° + 70°C, & 8.3×10 - 6/°F @ 20°C to 300°C |
| Surface finish | bk - 7 polishes extremely well & polishes of 10 - 5, or 20 - 10 scratch - dig are achieved at extra costs respectively, mainly for uv & visible applications. |
| Curvature diagram | surface figure of 1/10 wave to 1/4 wave @ 0.6328μm are specified mostly on lenses for ultraviolet & visible use. |
| Coating | ar @ 0.8 - 2.5μm, ar @ 1.064, ar @ visible wavelength. |
| Applications | Astronomy, thermal imaging |
| Products manufactured | Lenses, prisms, filters, optical filters, etc. |
| Wavelength | Refractive index (n) |
| 0.4047 | 1.53 |
| 0.48 | 1.523 |
| 0.5461 | 1.519 |
| 0.6328 | 1.515 |
| 0.8521 | 1.51 |
| 1.06 | 1.507 |
| 1.53 | 1.501 |
| 1.97 | 1.495 |
| 2.325 | 1.489 |

As a leading manufacturer in the Yangtze River Delta Integrated Demonstration Zone (Jiashan, Zhejiang), Jiangnan Outdoor has been awarded "National High-Tech Enterprise" and "Jiaxing Green Factory" titles, with full certifications in ISO 9001:2015, ISO 14001:2015, and ISO 45001:2018 international standards.