LAKN8 by Sumita
Obsolete
Very Rare
Environmentally Dangerous
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) | 1.678 |
|---|---|
| Abbe Number (Vd) | 50.7 |
| Dispersion Formula | Schott |
| Wavelength Range | 0.27 — 2.0 µm |
$$n(\lambda) = \sqrt{2.75352 - 0.00810902\,\lambda^2 + 0.023318\,\lambda^{-2} - 0.000656777\,\lambda^{-4} + 0.000137244\,\lambda^{-6} - 5.63523 \times 10^{-6}\,\lambda^{-8}}$$
Thermal Properties
| TCE -30/70°C (10-6/K) | — |
|---|---|
| TCE 100/300°C (10-6/K) | 8.3 |
| Thermal Conductivity (W/mK) | — |
| Heat Capacity (J/gK) | — |
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[0 + 2(0)\,\Delta T + 3(0)\,\Delta T^2 + \frac{0 + 2(0)\,\Delta T}{\lambda - 0}\right]
\Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
| Density (g/cm³) | 3.8 |
|---|---|
| Relative Cost | — |
Mechanical Properties
| Young's Modulus (GPa) | — |
|---|---|
| Poisson's Ratio | — |
| Knoop Hardness (kgf/mm²) | — |
Chemical Resistance
| Climatic Resistance | 1 |
|---|---|
| Stain Resistance | — |
| Acid Resistance | 4 |
| Alkali Resistance | — |
| Phosphate Resistance | — |
Similar Glasses (Other Manufacturers)
| Glass | Manufacturer | nd | Vd | |
|---|---|---|---|---|
| S-LAL56 | Ohara | 1.677898 | 50.722184 | |
| LAL56 | Ohara | 1.677898 | 50.723364 | |
| LACL9 | Hoya | 1.6779 | 50.551353 | |
| LACL4 | Hoya | 1.669603 | 51.65903 | |
| H-LAK67 | CDGM | 1.67 | 51.738482 | |
| LAFL1 | Hoya | 1.686004 | 49.347081 | |
| LAFN23 | Schott | 1.689004 | 49.711581 | |
| C90-50 | Corning | 1.689009 | 49.625392 | |
| LAFL23 | Hoya | 1.689 | 49.475821 | |
| LAL58 | Ohara | 1.693495 | 50.807634 |