F2

BK7, SF11, LaSFN9, BaK1, and F2 are the most important optical and physical constants for Schott optical glass types. These types are used in most Dream Lasers simple lens products and prisms. The most commonly required chemical characteristics and mechanical constants, are listed. Further numerical data and a more detailed discussion of the various testing processes can be found in the Schott Optical Glass catalog.

F2 Constants
Abbé Constant
36.37
Density
3.61 g/cm-3
Young's Modulus
5.70 x 109 dynem2
Poisson's Ratio
0.220
Coefficient of Thermal Expansion (-30° to +70°C)
8.2 x 10-6/°C
Coefficient of Thermal Expansion (20° to 3000°C)
9.2 x 10-6/°C
Stress Birefringence, (Yellow Light)
10 nm/cm
Melt-to-Melt Mean Index Tolerance
±0.001
Homogeneity within Melt
±1x10-4
Striae Grade (MIL-G-174-A)
A
Transformation Temperature
438°C
Climate Resistance
1
Stain Resistance
0
Acid Resistance
1.0
Alkali Resistance
1.3
Phosphate Resistance
1.3
Knoop Hardness
420
Dispersion Constants
B1 = 1.34533359 
B2 = 2.09073176x10-1 
B3 = 9.37357162x10-1
C1 = 9.97743871x10-3 
C2 =4.70450767x10-2 
C3 = 1.11886764x102
The external transmittance of F2 is shown in the figure below:
External transmission for 10-mm-thick F2 glass