ALKOR Technologies - your CRYSTAL optics supplier.   ALKOR Technologies - your CRYSTAL optics supplier.
ALKOR Technologies - your CRYSTAL optics supplier.
Materials>>Fused Silica windows

Fused Silica windows and lenses

Alkor Technologies - manufacturer of IR and UV Fused Silica optical components.
We supply the following Fused Silica optics:
- Fused Silica windows up to 210mm diameter;
- Fused Silica lenses with any desired focal length;
- Fused Silica wedged windows and Fused Silica prisms;
- Fused Silica mirrors with Protected Aluminum or Protected Gold coatings.
Please send us your specifications, we will quote it for you within 24 hours.

Fused Silica available in UV and IR grades for different applications:

1. KU-1 - Ultraviolet grade (UV) Fused Silica (SiO2)

KU-1 - UV Fused Silica has high transparency within ultraviolet and visible regions. It has no absorption bands within 170-250 nm wavelength interval. It has an intensive OH-absorption band at 2600-2800nm wavelength range. This grade does not express fluorescence as a result of UV excitation, and is characterized by optical-radiation stability. It is practically free from bubbles and inclusions.
The nearest analogues of quartz glass KU-1 are:
Suprasil Standard (Heraeus), Spectrosil A and B (Saint-Gobain), Corning HPFS 7980 (in stock) , JGS1, Dynasil 1100 and 4100 (Dynasil).
KU-1 Fused Silica Windows are in UV grade material and usable down to 170nm.
Maximum dimensions: Dia 300x100mm. Contact us for further information.

Fused Silica transmission. Window thickness 10mm

KU-1 Fused Silica Transmission (10 mm thickness, reflective losses included)

2. KI - Infrared grade Fused Silica (low OH, water free)

KI - IR Fused Silica features high transparency within visible and infrared regions. It has no OH-absorption bands within 2600-2800 nm wavelength interval. Extremely low bubble and inclusion content (0.3 defects/100cm3 of defects larger than 200 microns), low-OH (<50ppm OH), low cost.
Infrared fused silica windows with low "OH" content can be used for applications requiring IR transmission to about 2900-3500nm. IR Fused Silica windows and mirrors by Alkor works in European gas analyzers and gas detectors.
Maximum dimensions: Dia400x250mm. Contact us for furhter information.

IR grade Fused Silica transmission

KI IR Fused Silica Transmission (10 mm thickness, reflective losses included)

For large quantity Heraeus Quartz glass can be requested (Suprasil 3001, Suprasil 3002, Spectrosil, Infrasil and more).

Fused Silica is used for windows, lenses and prisms in the transmission range 0.16-3.5m. Fused Silica refractive index varies from 1.55 to 1.40 through the transmission range. It is resistant to scratching and thermal shock.

Fused Silica is suitable for applications in the UV, VIS, IR band and is often used as a viewport window. We provide a large variety of Fused Silica windows for vacuum viewports suitable for ISO-K, KF and flanges. AR and Reflective Coatings are available for Fused Silica optics.

Transmission Range : 0.18 to 2.2 μm (3 μm for IR grades)
Refractive Index : 1.47012 at 4 μm (1)
Reflection Loss : 7.0% at 0.4 μm (2 surfaces)
Absorption Coefficient : 10 x 10-6 cm-1 at 1 μm
Reststrahlen Peak : n/a
dn/dT : +11.9 x 10-6 /C
dn/dμ = 0 : 1.3 μm
Density : 2.203 g/cc
Melting Point : 1600 C (softening)
Thermal Conductivity : 1.38 W m-1 K-1
Thermal Expansion : 0.55 x 10-6 /C at 300K
Hardness : Knoop 500 with 200g indenter
Specific Heat Capacity : 703 J Kg-1 K-1
Dielectric Constant : 3.78 at 25GHz
Youngs Modulus (E) : 73.1 GPa
Shear Modulus (G) : 31.2 GPa
Bulk Modulus (K) : 36.7 GPa
Elastic Coefficients : n/a
Apparent Elastic Limit : 55 MPa (7980 psi)
Poisson Ratio : 0.17
Solubility : Insoluble in Water
Molecular Weight : 28.09
Class/Structure : Amorphous glass

Standard Specifications High Precision
Material UV or IR Fused silica
Dimensions 0.00/-0.10mm +0.00/-0.05mm
Thickness 0.10mm 0.05mm
Surfaces 60/40 20/10
Edges Fine Ground Polished
Flatness ≤5 Fringes 0.1 fringes
Parallelism ≤ 3 Arc mins 30 Arc seconds

See also: Sapphire optics