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ALKOR Technologies - your CRYSTAL optics supplier.
Materials>>Sapphire windows

Sapphire windows, Sapphire lenses, Sapphire blanks.

Sapphire windows are ideal for vacuum chambers, submarine and other harsh environment applications. We provide sapphire windows and sapphire lenses according to customer's specifications.

Please contact us us for quotation of your Sapphire windows or lenses. Our Sales Team will prepare an answer within 24 hours. If you do not see a suitable size in catalogue, write a request, we will make Sapphire windows according to your drawing at no additional cost. The largest dimensions of Sapphire window - Diameter 100mm. Rectangular Sapphire windows are also available.

Sapphire window feature:

  • Extreme Surface Hardness Chemical Resistance
  • Transmits Wavelengths Ranging From UV to Mid-Infrared
  • Thinner and Stronger than Standard Glass Windows
  • Sapphire window: Design of pressure windows in Excel file

Sapphire transmission curve

See also: Material datasheet; Sapphire lenses; Sapphire windows from stock;

Sapphire windows

Sapphire is used for windows in 250-5000nm wavelength range. It is recognized as a highly important optical material because optical grade sapphire combines high transmission with outstanding mechanical-strength properties at high temperatures. Sapphire windows can be made thinner than alternative crystals thanks to its structural integrity and can operate up to 2030⁰C.

Sapphire windows are widely used as protective windows or viewports. Sapphire windows are ideal for applications where high pressure, vacuum, or corrosive atmospheres are a consideration.

Sapphire optical properties, chemical, mechanical properties
Transmission Range 0.17 to 5.5 μm
Refractive Index No 1.75449; Ne 1.74663 at 1.06 μm (1)
Reflection Loss 14% at 1.06 μm
Absorption Coefficient 0.3 x 10-3 cm-1 at 2.4 μm (2)
Reststrahlen Peak 13.5 μm
dn/dT 13.1 x 10-6 at 0.546 μm (3)
dn/dμ = 0 1.5 μm
Density 3.97 g/cc
Melting Point 2040C
Thermal Conductivity 27.21 W m-1 K-1 at 300K
Thermal Expansion 5.6 (para) & 5.0 (perp) x 10-6/K *
Hardness Knoop 2000 with 2000g indenter
Specific Heat Capacity 763J Kg-1 K-1 at 293K (4)
Dielectric Constant 11.5 (para) 9.4 (perp) at 1MHz
Youngs Modulus (E) 335 GPa
Shear Modulus (G) 148.1 GPa
Bulk Modulus (K) 240 GPa
Elastic Coefficients C11=496 C12=164 C13=115 C33=498 C44=148
Apparent Elastic Limit 300 MPa (45,000 psi)
Poisson Ratio 0.25
Solubility 98 x 10-6 g/100g water
Molecular Weight 101.96
Class/Structure Trigonal (hex), R3c

Wavelength,μm
No
Ne
0.193
1.92879
1.91743
0.213
1.88903
1.87839
0.222
1.8754
1.86504
0.226
1.87017
1.85991
0.244
1.85059
1.84075
0.248
1.84696
1.83719
0.257
1.83932
1.82972
0.266
1.83304
1.82358
0.280
1.82437
1.81509
0.308
1.81096
1.80198
0.325
1.80467
1.79582
0.337
1.80082
1.79206
0.351
1.79693
1.78825
0.355
1.79598
1.78732
0.442
1.78038
1.77206
0.458
1.77843
1.77015
0.488
1.7753
1.76711
0.515
1.77304
1.76486
0.532
1.7717
1.76355
0.590
1.76804
1.75996
0.633
1.7659
1.75787
0.670
1.76433
1.75632
0.694
1.76341
1.75542
0.755
1.76141
1.75346
0.780
1.76068
1.75274
0.800
1.76013
1.7522
0.820
1.75961
1.75168
0.980
1.75607
1.81974
1.064
1.75449
1.74663
1.320
1.75009
1.74227
1.550
1.74618
1.73838
2.010
1.73748
1.72973
2.249
1.73232
1.72432
2.703
1.719
1.711
2.941
1.712
1.704
3.333
1.701
1.693
3.704
1.687
1.679
4.000
1.674
1.666
4.348
1.658
1.65
4.762
1.636
1.628
5.000
1.623
1.615
5.263
1.607
1.599

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