1. Home
  2. Products
  3. Special Materials
  4. IR Materials
  5. Witness Samples - IRG Chalcogenide
  6. IRG 27
All

    IRG 27

    IRG 27 exhibits excellent transmission through the short and mid-wave IR (SWIR-MWIR). The germanium-free composition offers various advantages, including a near zero dn/dT starting at 1.5 μm that continues through the MWIR and into the LWIR.

    IRG 27 displays low dispersion for SWIR and MWIR applications and can be used as a flint material in achromatic doublets for multi-band IR applications.

    The glass can be processed by conventional grinding and polishing methods, as well single point diamond turning, and molding. Based on similar thermal and mechanical characteristics to IRG 26, IRG 27 will be processed in a similar manner.

    IRG 27
    IR characteristics
    Composition As2S3
    Density 3.20 g/cm3
    Thermal Expansion (20°C-100°C) 22.5·10-6/K
    Transition Temperature 197°C
    Thermal Change dn/dT (at 1 µm) 15.6·10-6/K
    Thermal Change dn/dT (at 5 µm) -3.2·10-6/K
    Thermal Change dn/dT (at 10 µm) -3.7·10-6/K
    Refractive Index (n at 10 µm) 2.3873
    Surface quality 60/40 polished both sides
    Surface flatness ≤ 5 waves P-V per surface at 632.8nm
    Edge Worked Saftety bevel
    Select product
    SCHOTT Article
      €00.00
      Need help or a quote?
      CONTACT OUR SUPPORT
      Download Data sheet IRG 27
      Article Details
       
      Technical Details
      Internal Transmittance (Chart)
      Internal Transmittance (Table)
      Wavelength
      [µm]      		 Transmission
      (10 mm)      		 Transmission
      (2 mm)      		 Extinction
      [cm-1]
      0.6 5.8 56.5 2.853
      0.7 93.3 98.6 0.070
      0.8 95.7 99.1 0.044
      1.0 97.2 99.4 0.028
      1.5 98.7 99.7 0.013
      2.0 99.0 99.8 0.010
      2.5 99.1 99.8 0.009
      3.0 98.5 99.7 0.015
      3.5 98.9 99.8 0.011
      4.0 87.1 97.3 0.138
      4.5 99.2 99.8 0.008
      5.0 99.5 99.9 0.005
      5.5 99.5 99.9 0.005
      6.0 99.2 99.8 0.008
      Wavelength
      [µm]      		 Transmission
      (10 mm)      		 Transmission
      (2 mm)      		 Extinction
      [cm-1]
      6.5 99.0 99.8 0.010
      7.0 97.8 99.5 0.023
      7.5 96.5 99.3 0.036
      8.0 96.5 99.3 0.035
      8.5 91.0 98.1 0.094
      9.0 69.3 92.9 0.367
      9.5 46.8 85.9 0.760
      10.0 38.8 82.8 0.946
      10.5 44.9 85.2 0.801
      11.0 43.9 84.8 0.822
      11.5 28.2 77.7 1.264
      12.0 11.8 65.2 2.137
      12.5 1.6 43.5 4.158
      12.7 0.1 24.5 7.026
      Material Data
      Constants of Dispersion Formulas
      B1 1.4005
      B2 3.4429
      B3 1.0394
      C1 0.0000
      C2 0.0871
      C3 805.5000
      D0 -3.89·10-6
      E0 1.77·10-5
      λTK 2.46·10-1
      Calculation Formula: Refractive index as a function of wavelength and temperature
      Wavelength
      [µm]      		 Refractive Index
      (@ 22 °C)      		 Δn abs/ΔT [10–6/K]
      22 °C
      0.6 2.6347 62.2
      0.7 2.5665 40.6
      0.8 2.5268 28.4
      0.8 2.5014 20.7
      0.9 2.4841 15.6
      1.0 2.4452 4.3
      1.5 2.4320 0.6
      2.0 2.4257 -1.0
      3.0 2.4218 -1.9
      4.0 2.4169 -2.8
      5.0 2.4129 -3.2
      6.0 2.4090 -3.4
      7.0 2.4046 -3.5
      8.0 2.3997 -3.6
      9.0 2.3939 -3.6
      10.0 2.3873 -3.7
      11.0 2.3795 -3.7
      12.0 2.3705 -3.7
      Wavelength
      [µm]      		 Thermal Change
      [dn/dt]
      1 µm 15.6·10-6/K
      5 µm -3.2·10-6/K
      10 µm -3.7·10-6/K
      Back