Faraday rotator glass
has been used for magneto-optical isolator,
switch, modulator and sensor. Faraday rotator glasses have been developed by LLG. TG20 is a high Verdet constant glass in common uses. TGP20 is characterized by a high Verdet constant and a lower nonlinear refractive index n2 to avoid self-focusing in high power laser system. |
|
|
TG20
|
TGL20
|
|
Verdet constant V (min/Oe.cm) |
|
|
|
632.8nm |
-0.258 |
-0.149 |
|
1064nm |
-0.075 |
-0.05 |
|
Refractive Index nd |
1.6888 |
1.5588 |
|
Abbe Number |
53.14 |
62.92 |
|
Nonlinear refractive index (10-13 e.s.u.) |
2.46 |
1.34 |
|
Thermal coefficient of refractive index (10-7/¡æ) |
74 |
6.9 |
|
Thermal coefficient of optical path (10-7/¡æ) |
105 |
46 |
|
Transmission window (nm) |
520-1400 |
520-1400 |
|
Coefficient of thermal expansion (10-7/¡æ) |
51.3 |
70 |
|
Transition temperature (¡æ) |
760 |
566 |
|
Sag temperature (¡æ) |
800 |
596 |
|
Density (g/cm3) |
4.32 |
3.32 |
|
Young¡¯s modulus GPa |
108 |
65.2 |
|
Poisson¡¯s ratio |
0.22 |
0.24 |
|
Knoop hardness (Kgf/cm2) |
760 |
515 |
|
Chemical durability |
Excellent |
Excellent |
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