Experimenter's Corner
Holography has a wealth of possibilities for the amateur and professional holographer, alike.
Ferric Ammonium Oxalate
Ferric ammonium oxalate (FAO) and possibly ferric ammonium citrate (FAC) have possibilities as a substitute for ammonium or potassium dichromate in gelatin. Experimentation is chronicled in two Holoforum threads: http://holoforum.org/forum/viewtopic.php?f=7&t=440 and http://holoforum.org/forum/viewtopic.php?f=7&t=497 . Test plates were fabricated using:
The coating thickness was estimated to be 7 to 9 microns. Plates were three days after coating. Geometry was a two-beam transmission grating at zero degrees and 24 degrees (~900 l/mm) at 457 nm from a solid state Melles Griot laser. The pictured plate was a 60 mJ exposure (mJ/cm^2?). Processing was as follows:
The second picture is a single-beam reflection hologram take with a 25 minute exposure. |