J. Phys. Radium
Volume 11, Numéro 7, juillet 1950
Page(s) 413 - 417
J. Phys. Radium 11, 413-417 (1950)
DOI: 10.1051/jphysrad:01950001107041300

Étude théorique de couches quintuples du type Ag-F 2Mg-Ag-F2Mg-Ag

Ch. Dufour

Compagnie des Compteurs

The theory of the interferometric combination formed by the coupling of two Fabry-Perot etalons (with two films fused into one) can be applied to five-fold thin films of the type : metal, non-absorbing film, metal, non-absorbing film, metal. Such complex films can form monochromatic interference filters if certain conditions are fulfilled. Filters of maximum transparence and resolution are obtained if the two outer metal films together are identical with the one metal film in the middle which is much more dense. If the three semitransparent metal films are identical, a dichroitic filter is obtained. The principal interest of this combination of thin films consists in the achievement of great optical density far from the transmission band.

4279C - Filters, zone plates, and polarizers.
4225H - Interference.
4279W - Optical coatings.

Key words
optical filters -- light interference -- optical films