Magneto Optical Glass /Faraday rotator glass materials Tb-10, Tb-12 and Tb-15 are designed for laser light flux output control in the magnetic field in visible and near-IR spectral range. It is used in manufacture of faraday rotating components based on Faraday rotation of the light polarization plane, such as optical isolators,circulators, magneto-optical modulators, fast optical switches, interleavers, laser gyroscopes, goniometric devices, magneto-optic storage and optical information process system, current measuring transducers for magnetic field measuring and high-voltage transmission line, new generation current sensors, wave guides, astrology, spaceflight control, satellite survey and other functional devices.
In high power laser systems, optical isolators are necessary to prevent the destruction of laser disks or other optical components caused by reflected laser from target. Faraday Isolators are passive unidirectional, non reciprocal devices that utilize the phenomenon of Magneto-Optic Rotation to isolate the source from reflections in an optical system. The isolator protects the laser oscillator from optical feedback making Faraday Isolators a key component in many of today's laser systems.
Large aperture Faraday rotator glass with high Verdet constant (defined as the rotation per unit path per unit field strength) is used as rotator material to obtain large rotation angle of linearly polarized laser form the given length of glass at low intensity of magnetic field. The amount of polarization rotation is
where:
= polarization rotation angle
= Verdet constant of optical element
= longitudinal component of magnetic intensity vector
= optical path length
Since glass material in high power laser system is damaged as a consequence of self-focusing, low non-linear refractive index as well as high Verdet constant is important factors for Magneto-Optical Glass.
Our advantages
Magneto Optical Glass /Faraday Rotator Glass offer the following advantages:
* High Verdet constant
* Excellent homogeneity
* High damage threshold
* Broad wavelength range
* Better transparency properties
* Lower nonlinear refractive index
* Lower absorption co-efficient
* Lower cost
* Available in very large plates / disks
Specifications
|
Material |
Tb-10 |
Tb-12 |
Tb-15 |
|
Verdet constant(min·Oe-1·cm-1) |
|||
|
λ = 632.8 nm |
-0.26 |
-0.29 |
-0.33 |
|
λ = 1064 nm |
-0.075 |
-0.090 |
-0.11 |
|
Transmission window |
400nm-1600nm | ||
|
Transparence rate T% (Uncoated) |
89% |
87% |
85% |
|
Density(g/cm3) |
4.29 |
4.62 |
4.98 |
|
Refractive index(at 589.3 nm) |
1.6989 |
1.7279 |
1.7551 |
|
Abbe number |
53.1 |
53.7 |
53.4 |
|
Non-linear coefficient,n2(10-13esu) |
2.65 |
2.51 |
2.55 |
|
Thermal expansion coefficient |
50.6×10-7℃-1 |
60.5×10-7℃-1 |
63.2×10-7℃-1 |
|
Transformation temperature Tg(℃) |
683 |
732 |
788 |
|
Sag temperature Ts(℃) |
724 |
776 |
824 |
|
Optical losses at 632.8nm and 1064 nm(cm-1) |
0.001 |
0.001 |
0.001 |
|
Optical quality ,Δ n (cm-1) |
< 2×10-6 |
< 2×10-6 |
< 2×10-6 |
|
Bulk laser damage threshold 3ns pulse width at 1064 nm(J/cm2) |
>10 |
>10 |
>10 |
|
Chemical durability |
Excellent |
Excellent |
Excellent |
|
Elements maximum dimensions |
Φ400×35 mm |
Φ220×35mm |
Φ100×30 mm |
* Specifications and information are subject to change without prior notice.
State Key Laboratory of Transient Optics & Photonics, Xi'an Institute of Optics & Precision Mechanics, Chinese Academy of Sciences, Xi'an, 710068
Tel: 862988887605
Email: yshwang@opt.ac.cn
