Fused Silica Window

Fused Silica Windows is based on UV synthetic Corning 7980 fused silica.

This Fused silica shows better performance from the UV to the IR spectrum than BK7 windows.

Fused Silica is the best choice in terms of thermal stability. In addition to superior transmission characteristics, fused silica exhibits higher thermal properties, exceptional purity, and excellent environmental durability for applications.

Specifications: 

Material                                                           Fused Silica

Source/Grade                                                Corning HPFS 7980

Diameter Tolerance                                      +0.0 mm/-0.1 mm

Thickness Tolerance                                    +/-0.1mm 

Parallelism                                                      < 3 arc minute

Surface Quality                                              20-10 (Scratch/Dig)

Surface Figure                                               λ/10 @ 633 nm or better

Bevel                                                               0.25mm×45°

Clear Aperture                                               90%

Coating                                                           As Requested 

Corning HPFS 7980 Glass is a result of melting synthetically derived silicon dioxide and is used in many of the same applications as fused quartz. The main differences are that fused silica transmits better in the UV and fused quartz is lower in OH content. Both are highly pure, have high chemical resistance, good thermal shock resistance, and low thermal expansion coefficient.

Thermal Properties                                                                             Mechanical Properties

Thermal Coefficient of Expansion:   (0/300°C): 5.5 X 10 -7/°C                    Density:                          2.201 g/cm³

Annealing Point:                                  1042°C/1907.6 °F                                 Knoop Hardness:         522 Kg/mm²

Softening Point:                                    1585°C / 2885 °F                                Young's Modulus:        72.7 Gpa

Strain Point:                                           893°C/1639.4°F                                   Poisson's Ratio:            0.16

Optical Properties                                                                               Electrical Properties

Refractive Index:                                   1.45840 (589 nm)                               Dielectric Constant:     E=3.8

UV Grade Fused Silica Transmission Curve