Abbe Number (v_d):

72.24

Axis Orientation:

Random

Bevel:

Protective as needed

Birefringence (n_o-n_e):

0.008 for Visible Light Orthogonal to Optical Axis

Clear Aperture (%):

85

Clear Aperture CA (mm):

32.38

Diameter (mm):

38.10 +0.00/-0.13

Thickness (mm):

3.00 ±0.13

Coating:

Uncoated

Coefficient of Thermal Expansion CTE (10^-6/°C):

8.8

Density (g/cm³):

3.97

Edges:

Fine Ground

Index of Refraction n_d:

1.77

Knoop Hardness (kg/mm²):

1900

Parallelism (arcmin):

<3

Poisson's Ratio:

0.27

Substrate: Many glass manufacturers offer the same material characteristics under different trade names. Learn More

Sapphire (Al₂O₃)

Surface Flatness (P-V):

2λ per 25.4mm

Surface Quality:

60-40

Type:

Protective Window

Wavelength Range (nm):

330 - 5500

Young's Modulus (GPa):

435

Model Number:

AL-W-38-3

38.1mm Dia., 3mm Thick, Uncoated, ISP Optics Sapphire Window | AL-W-38-3