Optical glass

Faraday‑rotation glass (also known as Faraday‑rotating glass or magneto‑optical glass) is a specialized paramagnetic optical glass that exploits the Faraday magneto‑optic effect. Typically composed of a terbium‑doped (Tb³⁺) borosilicate system, it induces a directional rotation of the polarization plane of light in the presence of a magnetic field, exhibiting nonreciprocal behavior. It serves as a key material for fabricating optical isolators, optical switches, and modulators.

Keywords:

Product Category:

  • Product Introduction
  • Key advantages
  • Application areas
  • Product Features
    • Commodity name: Optical glass

    Faraday‑rotation glass (also known as Faraday‑rotating glass or magneto‑optical glass) is a specialized paramagnetic optical glass that exploits the Faraday magneto‑optic effect. Typically composed of a terbium‑doped (Tb³⁺) borosilicate system, it induces a directional rotation of the polarization plane of light in the presence of a magnetic field, exhibiting nonreciprocal behavior. It serves as a key material for fabricating optical isolators, optical switches, and modulators.

    Main advantages

    1. Strong optical rotation and a high Verdet constant  
    2. Excellent optical quality  
    Broadband high transmission (520–1400 nm)
    Low absorption, low scattering, high optical homogeneity, and low stress‑induced birefringence.
    3. Good thermal and chemical stability  
    Good resistance to heat, weathering, water, and weak acids.
    4. Large size, easy to process, low cost  
    Capable of handling large apertures (φ300mm class)
    5. Nonreciprocal Magneto-optical Properties  
    Strict unidirectional optical rotation is the indispensable core principle underlying optical isolators and circulators.

     

    Application areas

    1. Laser System: Optical Isolator (the most critical component)
    2. Optical Communication and Optical Information
    3. High-Power / Large-Aperture Laser System
    4. Sensing and Measurement
    5. Research and Instruments

     

    Product Features

    Optical Glass Grade Tb-20 Tb-25 Tb-30
    Feld Chang  
    (min·Oe-1·cm-1)
    λ = 632.8 nm -0.26 -0.29 -0.33
    λ = 1064 nm -0.075 -0.090 -0.11
    Through the window 400nm-1500nm
    Transmittance T% (uncoated) 89% 87% 85%
    Density (g/cm³) 4.29 4.62 4.98
    Refractive Index (ND) 1.6989 1.7219 1.7551
    Abbe number (vD) 53.1 52.2 51.4
    Nonlinear refractive index, n2 (10⁻¹³ esu) 2.65 2.68 2.78
    Coefficient of thermal expansion (°C⁻¹) 50.6×10⁻⁷ 60.5×10⁻⁷ 63.2×10⁻⁷
    Glass transition temperature Tg (°C) 683 732 788
    Softening temperature Ts (°C) 724 776 824
    Light absorption coefficient (cm⁻¹) 0.001 0.001 0.001
    Optical uniformity, Δn (cm⁻¹) < 2×10-6 < 2×10-6 < 2×10-6
    Laser damage threshold (3 ns pulse) >10 J/cm² >10 J/cm² >10 J/cm²
    Chemical stability Excellent Excellent Excellent
    Maximum component size Φ400×35 mm Φ220×35mm Φ100×30 mm

Online Quotation Request

Please provide your phone number and email address, and we’ll get in touch with you as soon as possible.

操作
Submit