Large size optics
Elan offers fabrication of large-size substrates and windows made
of various types of materials. Specification is listed below
|
|
| Material |
LK5, LK7 (equivalent to Pyrex) |
BK7 |
Fused |
Sitall
(equivalent to Pyrex)
|
| Refraction index, ne |
LK-5: 1,478162
LK-7: 1.482866
|
1.516369 |
1.460078 |
1.5447 |
| Linear expansion coefficient |
LK-5: 35•10-7
LK-7: 44•10-7 |
76 •10-7 |
5.5•10-7 |
0.5 •10-7 |
Dimensions
| Dimensions |
Diameter |
Up
to 400 mm |
 |
| Diagonal |
Specification
| |
Up to
200 mm |
Up to
300 mm |
Up to
400 mm |
| Surface quality |
S/D 20/10 |
| Surface flatness |
λ/4 |
λ/3 |
3λ/4 |
| Surface irragularity |
λ/10 |
λ/7 |
λ/4 |
|
