Specific Parameters for BARR's H Filters
- Thickness: 3.3 mm.
- Usable Aperture: 31 x 31 mm square.
- Special: Sandwich two glass layer construction.
Filter ID # | Short HPP (300K)
| Long HPP (300K) |
Short HPP (77K) | Long HPP (77K)
|
1 | 1.505
| 1.817 | 1.475
| 1.781 |
2 | 1.505
| 1.816 | 1.475
| 1.780 |
3 | 1.504
| 1.814 | 1.474
| 1.778 |
4 | 1.504
| 1.810 | 1.474
| 1.774 |
5 | 1.501
| 1.810 | 1.471
| 1.774 |
6 | 1.501
| 1.820 | 1.471
| 1.784 |
7 | 1.498
| 1.814 | 1.468
| 1.778 |
8 | 1.504
| 1.821 | 1.474
| 1.785 |
Note: BARR's measurements were performed at 300K. The values
given for 77K were calculated by applying a 2% blueward shift
to the wavelengths (expected shift to be from 1 - 3%).
All values given in nm.
Postscript of a typical transmission curve scan for a standard BARR H filter performed
at 77K.
François Piché
Latest Revision: July 11, 1997