| Revision: | 1.1 |
| Committed: | Sat Feb 22 02:07:21 2003 UTC (21 years, 2 months ago) by greg |
| Branch: | MAIN |
| CVS Tags: | rad5R2, rad4R2P2, rad5R0, rad5R1, rad3R7P2, rad3R7P1, rad4R2, rad4R1, rad4R0, rad3R5, rad3R6, rad3R6P1, rad3R8, rad3R9, rad4R2P1 |
| Log Message: | Changes and check-in for 3.5 release Includes new source files and modifications not recorded for many years See ray/doc/notes/ReleaseNotes for notes between 3.1 and 3.5 release |
| # | Content |
|---|---|
| 1 | { |
| 2 | These formulas compute the index of refraction and |
| 3 | normal transmission for a pane of glass given the |
| 4 | measured normal transmittance and reflectance values, |
| 5 | Tn and Rn, respectively. |
| 6 | |
| 7 | These formulas are approximate -- the exact solution |
| 8 | involves a quartic equation and seemed more trouble |
| 9 | than it was worth. If you know the index of refraction, |
| 10 | you are better off with the formula in trans.cal. |
| 11 | |
| 12 | Oct. 2002 Greg Ward |
| 13 | } |
| 14 | { formula for normal transmission } |
| 15 | tn = Tn / (1 - Rn); |
| 16 | F = Rn / (1 + tn*tn); |
| 17 | n = (1 + sqrt(F)) / (1 - sqrt(F)); |