Peoptix - Infrared Optics & Custom Optical Components
Peoptix - Infrared Optics & Custom Optical Components
BK7 Optical Windows (H-K9L, equivalent to SCHOTT N-BK7) are versatile protective optical components for visible and near-infrared optical systems. This window substrate features three core advantages: superior optical homogeneity, ultra-high transmittance over the 350 nm – 2.5 μm spectrum, and excellent thermal stability, perfect for precision optical instruments.
Key Advantages
BK7 Material Properties
|
Material |
H-K9L Borosilicate Crown Optical Glass, optically equivalent to SCHOTT N-BK7 |
|
Transmission Range |
350 nm – 2500 nm |
|
Refractive Index |
1.5168 @ 587.6 nm He d-line (20℃) |
|
Density |
2.51 g/cm³ (20℃) |
|
Coefficient of Thermal Expansion (CTE) |
7.1 × 10⁻⁶ /°C (-30°C to +70°C) |
|
Thermal Conductivity |
1.114 W/(m·K) |
|
Knoop Hardness |
610 HK (0.1 kgf / 20 s) |
|
Absorption Coefficient |
≈0.002 cm⁻¹ (Ultra-low absorption in visible & NIR bands) |
|
Young's Modulus (GPa) |
82 GPa |
|
Poisson's Ratio |
0.206 |
Processing Specifications
|
Parameters |
Regular |
High precision |
|
Dimension |
Φ2 mm - Φ300 mm |
|
|
Diameter Tolerance |
±0.1 mm |
±0.01 mm |
|
Thickness Tolerance |
±0.1 mm |
±0.02 mm |
|
Parallelism (arcmin) |
<1′ (1 arcmin) |
<10″ (10 arcsec) |
|
Surface Quality |
60-40 |
10-5 |
|
Surface Flatness (P-V) |
PV<λ/2@632.8 nm |
PV< λ/20@632.8 nm |
|
Coating |
AR, BBAR, HR, Metal Reflective Coating |
|
