K-BK7 by Sumita
Standard
Rare
Environmentally Friendly
Refractive Index vs Wavelength
Refractive Index Calculator
dn/dλ vs Wavelength
dn/dλ Calculator
Abbe Number Calculator
Transmission vs Wavelength
Transmission Calculator
Optical Properties
| Refractive Index (nd) | 1.51633 |
|---|---|
| Abbe Number (Vd) | 64.1 |
| Dispersion Formula | Schott |
| Wavelength Range | 0.36 — 1.55 µm |
$$n(\lambda) = \sqrt{2.27058 - 0.0100594\,\lambda^2 + 0.010415\,\lambda^{-2} + 0.000288725\,\lambda^{-4} - 2.22145 \times 10^{-5}\,\lambda^{-6} + 1.42586 \times 10^{-6}\,\lambda^{-8}}$$
Thermal Properties
| TCE -30/70°C (10-6/K) | 6.3 |
|---|---|
| TCE 100/300°C (10-6/K) | 8.5 |
| Thermal Conductivity (W/mK) | — |
| Heat Capacity (J/gK) | — |
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[6.84 \times 10^{-7} + 2(2.05 \times 10^{-8})\,\Delta T + 3(-1.55 \times 10^{-10})\,\Delta T^2 + \frac{4.18 \times 10^{-7} + 2(2.74 \times 10^{-10})\,\Delta T}{\lambda - 0.178}\right]
\Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
| Density (g/cm³) | 2.52 |
|---|---|
| Relative Cost | — |
Mechanical Properties
| Young's Modulus (GPa) | — |
|---|---|
| Poisson's Ratio | — |
| Knoop Hardness (kgf/mm²) | — |
Chemical Resistance
| Climatic Resistance | 1 |
|---|---|
| Stain Resistance | — |
| Acid Resistance | 1 |
| Alkali Resistance | — |
| Phosphate Resistance | — |
Similar Glasses (Other Manufacturers)
| Glass | Manufacturer | nd | Vd | |
|---|---|---|---|---|
| L-BSL7 | Ohara | 1.51633 | 64.065129 | |
| D-K9 | CDGM | 1.51633 | 64.058952 | |
| D-K9GT | CDGM | 1.51633 | 64.058952 | |
| P-BK7 | Schott | 1.5164 | 64.06 | |
| S-BSL7 | Ohara | 1.51633 | 64.142022 | |
| BK7HT | Schott | 1.51633 | 64.14348 | |
| BSL7 | Ohara | 1.51633 | 64.150145 | |
| BK7 | Schott | 1.5168 | 64.167336 | |
| N-BK7 | Schott | 1.5168 | 64.17 | |
| N-BK7HT | Schott | 1.5168 | 64.17 |
Similar Glasses (Sumita)
| Glass | Manufacturer | nd | Vd | |
|---|---|---|---|---|
| BK7 | Sumita | 1.51633 | 64.1 | |
| P-BK40 | Sumita | 1.5176 | 63.5 | |
| K-PBK40 | Sumita | 1.5176 | 63.5 | |
| K-PBK40(M) | Sumita | 1.51497 | 63.3 | |
| BK1 | Sumita | 1.51009 | 63.4 | |
| K-PBK50(M) | Sumita | 1.52025 | 62.2 | |
| K-PBK50 | Sumita | 1.5225 | 62.3 | |
| K-PBK60 | Sumita | 1.5274 | 62.3 | |
| K-PBK60(M) | Sumita | 1.52483 | 62.0 | |
| BK3 | Sumita | 1.49831 | 65.1 |