S-TIM25 by Ohara
Standard
Common
Environmentally Friendly
S-TIM25 by Ohara is a standard optical glass with a common melt frequency. It transmits from 0.36 to 2.40 µm with an nd of 1.6727 and a Vd of 32.099206. It has medium thermal expansion (CTE of 7.9×10⁻⁶/K), good chemical resistance, and low relative cost.
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) | 1.6727 |
|---|---|
| Abbe Number (Vd) | 32.099206 |
| Dispersion Formula | Sellmeier |
| Wavelength Range | 0.404656 — 2.32542 µm |
$$n(\lambda) = \sqrt{1 + \frac{1.50659\,\lambda^2}{\lambda^2 - 0.0109502} + \frac{0.204786\,\lambda^2}{\lambda^2 - 0.057498} + \frac{1.92037\,\lambda^2}{\lambda^2 - 178.129}}$$
Thermal Properties
| TCE -30/70°C (10-6/K) | 7.9 |
|---|---|
| TCE 100/300°C (10-6/K) | — |
| Thermal Conductivity (W/mK) | — |
| Heat Capacity (J/gK) | — |
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[-3.93 \times 10^{-7} + 2(1.2 \times 10^{-8})\,\Delta T + 3(-3.29 \times 10^{-11})\,\Delta T^2 + \frac{8.13 \times 10^{-7} + 2(1.17 \times 10^{-9})\,\Delta T}{\lambda - 0.284}\right]
\Delta T = T - T_0, \quad T_0 = 25\,°\text{C}$$
Chemical Resistance
| Climatic Resistance | 2 |
|---|---|
| Stain Resistance | — |
| Acid Resistance | 1 |
| Alkali Resistance | — |
| Phosphate Resistance | 1 |
Notes
Recommended
Similar Glasses (Other Manufacturers)
| Glass | Manufacturer | nd | Vd | Compare |
|---|---|---|---|---|
| E-FD5 | Hoya | 1.6727 | 32.17 | |
| H-ZF2 | CDGM | 1.6727 | 32.171186 | |
| FD5 | Hoya | 1.672701 | 32.173263 | |
| ZF2 | CDGM | 1.672707 | 32.180986 | |
| SF5 | Sumita | 1.6727 | 32.2 | |
| SF5 | Schott | 1.6727 | 32.21 | |
| N-SF5 | Schott | 1.67271 | 32.25 | |
| C72-32 | Corning | 1.672698 | 32.31788 | |
| SF19 | Schott | 1.6668 | 33.005581 | |
| H-ZF39 | CDGM | 1.6668 | 33.053728 |
Similar Glasses (Ohara)
| Glass | Manufacturer | nd | Vd | Compare |
|---|---|---|---|---|
| PBM25 | Ohara | 1.6727 | 32.101636 | |
| PBM39 | Ohara | 1.666799 | 33.046816 | |
| S-TIM39 | Ohara | 1.6668 | 33.054985 | |
| PBM28 | Ohara | 1.68893 | 31.082901 | |
| PBM28W | Ohara | 1.68893 | 31.082901 | |
| S-TIM28 | Ohara | 1.688931 | 31.07545 | |
| L-TIM28 | Ohara | 1.689479 | 31.023399 | |
| L-TIM28P | Ohara | 1.694529 | 30.655992 | |
| S-TIM22 | Ohara | 1.647689 | 33.792803 | |
| PBM22 | Ohara | 1.647689 | 33.802937 |