LAF70 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) | 1.7495 |
|---|---|
| Abbe Number (Vd) | 35.0 |
| Dispersion Formula | Schott |
| Wavelength Range | 0.27 — 2.0 µm |
$$n(\lambda) = \sqrt{2.96739 - 0.0129794\,\lambda^2 + 0.0305856\,\lambda^{-2} + 0.00114095\,\lambda^{-4} - 3.36726 \times 10^{-5}\,\lambda^{-6} + 6.97337 \times 10^{-6}\,\lambda^{-8}}$$
Thermal Properties
| TCE -30/70°C (10-6/K) | — |
|---|---|
| TCE 100/300°C (10-6/K) | 6.9 |
| 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) | 4.4 |
|---|---|
| Relative Cost | — |
Mechanical Properties
| Young's Modulus (GPa) | — |
|---|---|
| Poisson's Ratio | — |
| Knoop Hardness (kgf/mm²) | — |
Chemical Resistance
| Climatic Resistance | 1 |
|---|---|
| Stain Resistance | — |
| Acid Resistance | 5 |
| Alkali Resistance | — |
| Phosphate Resistance | — |
Similar Glasses (Other Manufacturers)
| Glass | Manufacturer | nd | Vd | |
|---|---|---|---|---|
| H-LAF4GT | CDGM | 1.7495 | 34.989266 | |
| H-LAF4 | CDGM | 1.7495 | 34.989266 | |
| E-LAF7 | Hoya | 1.7495 | 35.04 | |
| LAF7 | Hoya | 1.749497 | 35.042695 | |
| LAFN7 | Schott | 1.7495 | 34.95 | |
| N-LAF7 | Schott | 1.7495 | 34.82 | |
| LAM7 | Ohara | 1.749497 | 35.278026 | |
| S-LAM7 | Ohara | 1.749497 | 35.283397 | |
| S-NBH51 | Ohara | 1.749504 | 35.33248 | |
| NBFD6 | Hoya | 1.756702 | 36.345258 |