| Filter | Test method | f-ratio | Surface measured | FSR | FWHM | BW at 10% peak transmission | delta CWL | |
| Alluxa Ha 10 A | Sol'Ex spectro | f/35 |
10 micron x 4.5 mm | 10.0 A (normal incidence) |
14.0 A (normal incidence) |
+ 1 A | Peak transmission : > 85% 3-cavity filter (BW at 10% < 1.5 FWHM) |
|
3-cavity filter (BW at 10% < 1.5 FWHM)
Temperature coefficient = 0.05 A/°C
Borofloat substrate
Temperature coefficient = 0.05 A/°C
Borofloat substrate
Measurement in f/35 telecentric beam
Optical setup: Sun => C8 EdgeHD => f/35 telecentric => Solex
Sol'Ex spectrograph : 10 microns slit, 200 mm collimating lens, 2400 l/mm garting, 200 mm imaging lens, ASI290 camera, 12-bit acquisition.
Dispersion = 0.0471 A/pixel.
Two succesive images :
- solar spectrum,
- solar spectrum transmitted by the Alluxa 10 A at normal incidence,.
- solar spectrum,
- solar spectrum transmitted by the Alluxa 10 A at normal incidence,.
Measured peak transmission :> 85%
