22 May 2019 Description
Faraday rotator glass is a kind of magneto-optical glasses with good transmittance in the visible and infrared range（520～1400nm）. Faraday rotator glass is more suitable for medium and low power level lasers, and is cheaper compared with the other magneto-optic crystals such as TGG,TSAG. TG20 has been used widely in switch, modulator, sensor, magneto-optical isolator.
Parameter
Material and Specifications
| Diameter Tolerance |
< λ/8 @ 633nm |
|
| Length Tolerance |
±0.05mm |
|
| Flatness |
<λ/8 @ 633nm |
|
| Surface Quality |
10/5 scratch/dig |
|
| Parallelism |
< 5 seconds |
|
| Clear Aperture |
>90% |
|
| Edge Chamfer |
0.1mm x 45° |
|
Physical and Chemical Properties
| Materials |
TG20 |
TG28 |
| Thermal Coefficient of Refractive Index (10-7 /℃) |
74 |
– |
| Thermal Coefficient of Optical Path (10-7 /℃) |
105 |
– |
| Transmission Window (nm) |
520-1400 |
520-1400 |
| Coefficient of Thermal Expansion (10-7 /℃) |
51.3 |
69 |
| Transition Temperature (℃) |
760 |
759 |
| Sag Temperature (℃) |
800 |
800 |
| Density (g/cm 3 ) |
4.32 |
4.99 |
| Young’s Modulus GPa) |
108 |
|
| Poisson’s Ratio |
0.22 |
|
| Knoop Hardness (Kg/cm2 ) |
760 |
|
Optical and Spectral Properties
| Materials |
TG20 |
TG28 |
| Refractive Index (1064nm) |
1.6721 |
1.736 |
| Refractive Index (d 589.3nm) |
1.6888 |
1.75 |
| Nonlinear Refractive Index (10-13 e.s.u .) |
2.46 |
2.42 |
| Abbe Number |
53.14 |
50.98 |
Verdet Constant
| Materials |
TG20 |
TG28 |
| Verdet Constant V (min/Oe.cm): 632.8nm |
-0.258 |
-0.361 |
| Verdet Constant V (min/Oe.cm): 1064nm |
-0.075 |
-0.106 |
Features
-
High verdet constant
-
Good chemical durability
-
Excellent transparency
Applications
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