Dielectric optical switch
AssigneeThe United States of America as represented by the Secretary of the Air Force
InventorRobert J. Spry
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Abstract
A novel optical filter structure for selectively blocking radiation of predetermined wavelength is described which comprises a plurality of alternate first and second layers deposited on a substantially transparent substrate, the first layers comprising a transparent nontransitioning material of first refractive index, the second layers comprising a material characterized by a transition from ferroelectric phase having second refractive index to nonferroelectric phase having third refractive index different from the first and second indices upon being heated to a characteristic transition temperature, each of the first and second layers having a thickness substantially equal to one-fourth times the ratio of the predetermined wavelength to the respective index of refraction.
Claims6
An optical filter structure for selectively block radiation of preselected wavelength, comprising:
- (a) a substantially transparent substrate;
- (b) a plurality of alternate substantially identical first layers and substantially identical second layers on said substrate, wherein said first layers comprise a transparent material of preselected first refractive index, and said second layers comprise a material having a substantially transparent ferroelectric phase of second refractive index below a characteristic transition temperature and a nonferroelectric phase of third refractive index different from said first refractive index and from said second refractive index above said characteristic transition temperature, said first layers having said first refractive index above and below said characteristic transition temperature;
- and
- (c) wherein the thickness of each of said first layers is equal to one-fourth times the ratio of said preselected wavelength to said first refractive index and the thickness of each of said second layers is equal to one-fourth times the ratio of said preselected wavelength to said third refractive index.
Dependencies are inferred from the claim text.