Abbe Number (v_d):

64.17

Bevel:

Protective as needed

Clear Aperture CA (mm):

22.50 x 22.50

Dimensions (mm):

25.00 x 25.00

Thickness (mm):

4.00 ±0.20

Coating:

MgF₂ (400-700nm)

Coating Specification:

MgF₂: ¼λ @ 550nm, R_avg ≤1.75% @ 400 - 700nm

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

7.1 (-30 to +70°C)
8.3 (+20 to +300°C)

Density (g/cm³):

2.51

Edges:

Fine Ground

Index of Refraction n_d:

1.516

Knoop Hardness (kg/mm²):

610

Parallelism (arcmin):

≤5

Poisson's Ratio:

0.206

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

N-BK7

Surface Accuracy:

1λ

Type:

Protective Window

Wavelength Range (nm):

400 - 700

Young's Modulus (GPa):

82

Length (mm):

25.00

Width (mm):

25.00

25 x 25 x 4mm MgF₂ Coated, N-BK7 Window

25 x 25 x 4mm MgF2 Coated, N-BK7 Window