THREE-LAYER REFLECTION-REDUCING COATINGS FOR OPTICAL ELEMENTS,
Abstract
An investigation was made of three-layered reflectionreducing films similar in principle to those recently developed in Germany. Very effective coatings have been produced by use of materials of the type developed by the American Optical Company. The maximum expected reduction in reflection has not been obtained, however, because none of the available materials has a high enough refractive index. The difficulty involved in the preparation of the coatings probably makes them undesirable for general use but they may be suitable for special uses where the greatest possible reduction in reflection is required. For the latter cases, it might be desirable to produce these coatings through use of an evaporation process similar to that now used to produce magnesium fluoride coatings or through a vapordeposition process similar to the German one, since materials of higher index are available through these techniques and three-layered coatings of lower reflection are thus possible. The three-layered reflection-reducing coatings produced through the use of the American Optical Company type solutions are sufficiently durable to withstand normal usage but they are not as resistant to abrasion as the best grade of evaporated magnesium fluoride coatings. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 29, 1946
- Accession Number
- AD0623520
Entities
People
- L. B. Lockhart
Organizations
- United States Naval Research Laboratory