BK7 Windows
What is N-BK7 optical windows
N-BK7 optical windows are made of N-BK7, a borosilicate crown optical glass, which is designed by SCHOTT. H-K9L is the equivalent material of N-BK7 from CDGM, which is the largest supplier of optical materials in China. CLZ Optical Co., Ltd. provides you custom N-BK7 windows with excellent performance at an reasonable price.
N-BK7 is a hard glass that can withstand a wide range of physical and chemical stimuli. It is relatively scratch and chemical resistant. It is well suited for precision lenses because of its low bubble and impurity content.
N-BK7 is designed and produced by Schott, Germany, and is widely used in a variety of visible light and short-wave infrared applications. Compared with other similar glass, its advantages are mainly reflected in the following aspects:
1. High performance and low cost
2. Good material consistency
3. High refractive index uniformity
4. Low stress birefringence
5. Low bubble and streakiness
Characteristics of N-BK7
The high quality of optical materials is reflected in their homogeneity and, more specifically, in the extremely narrow range of refractive indices throughout the glass. Optical glass for high-power lasers and astronomical applications therefore requires particularly high homogeneity.
1. N-BK7 can withstand low transition temperatures, mostly below 550°C, which improves mold life and shortens press time.
2. Will have a low tendency to react chemically with the mold material within the molding temperature range
3. Has tight optical tolerances
4. Available in a wide range of glass sizes
5. Multiple forms of supply for optical raw materials, optical blanks, optical parts, etc.
The chemical properties of BK7 are very stable, so it possesses scratch resistance and corrosion resistance. Meanwhile special grinding and polishing processes are not required, thereby reducing manufacturing costs. BK7 has a high degree of purity and homogeneity. It is nearly free of bubbles and inclusions. The BK7 is clear and colorless, and has very high transmittance in the visible and near-infrared spectrum (350 nm-2.0 µm). Therefore, it is suitable for most spectral ranges and has become the most widely used glass material.
However, if you need further applications in the UV spectrum or a lower coefficient of thermal expansion, we recommend that you use UV Fused Silica windows.
The highest standard for BK7 windows is 10-5 scratch dig, which reaches precision laser quality. BK7 windows are an economical choice for low power lasers and medium power lasers. Because of high transmittance in the visible light range, BK7 windows can be used in imaging systems as protective displays for a variety of industrial or environmental applications.
CLZ Optical Co., Ltd. can provide you with a range of high-quality N-BK7 windows,Precision grade optical windows including N-BK7 round windows, N-BK7 square windows, step windows, N-BK7 precision windows, custom N- BK7 windows.
Special coatings are available, such as BBAR, short or long pass, V or W coatings. AR coatings can be effectively used for multiple visible wavelengths and tunable lasers without multiple sets of optical elements.
