LAK9 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) | 1.691 |
|---|---|
| Abbe Number (Vd) | 54.8 |
| Dispersion Formula | Schott |
| Wavelength Range | 0.27 — 2.0 µm |
$$n(\lambda) = \sqrt{2.80649 - 0.0120282\,\lambda^2 + 0.0184837\,\lambda^{-2} + 0.000473212\,\lambda^{-4} - 1.83077 \times 10^{-5}\,\lambda^{-6} + 1.18242 \times 10^{-6}\,\lambda^{-8}}$$
Thermal Properties
| TCE -30/70°C (10-6/K) | — |
|---|---|
| TCE 100/300°C (10-6/K) | 8.6 |
| 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) | 4.06 |
|---|---|
| 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 | |
|---|---|---|---|---|
| C90-55 | Corning | 1.691008 | 54.793839 | |
| H-LAK59A | CDGM | 1.691 | 54.815309 | |
| S-LAL9 | Ohara | 1.691002 | 54.822578 | |
| LAL9 | Ohara | 1.691002 | 54.84322 | |
| LAK9G15 | Schott | 1.69064 | 54.76 | |
| N-LAK9 | Schott | 1.691 | 54.71 | |
| LAK9 | Schott | 1.691002 | 54.708408 | |
| LAC9 | Hoya | 1.691 | 54.7 | |
| H-LAK2A | CDGM | 1.69211 | 54.539198 | |
| N-LAK14 | Schott | 1.6968 | 55.41 |