Samuel Y Lu

US Patent:

54575702, Oct 10, 1995

Filed:

May 25, 1993

Appl. No.:

8/067863

Inventors:

Samuel Lu - Agoura CA
Alan F. Stewart - Thousand Oaks CA
Anthony W. Louderback - Eugene OR

Assignee:

Litton Systems, Inc. - Beverly Hills CA

International Classification:

G02B 520

US Classification:

359361

Abstract:

A coating for an optical component is formed to be antireflective for a selected wavelength and resistive to the transmission of ultraviolet radiation. The coating has first layer is formed of a dielectric material having a refractive index n. sub. 1 coated onto the optical component. A second layer is formed of a dielectric layer having a refractive index n. sub. 2 that is smaller than the refractive index n. sub. 1 of the first layer. The second layer is formed of a material that transmits the selected wavelength while blocking ultraviolet light, thereby protecting the first layer and the optical component from damage due to exposure to ultraviolet radiation. The thicknesses of the layers is selected so that the coating is antireflective for the selected wavelength.

US Patent:

55130399, Apr 30, 1996

Filed:

May 26, 1993

Appl. No.:

8/067385

Inventors:

Samuel Lu - Agoura CA
Alan F. Stewart - Thousand Oaks CA
Anthony W. Louderback - Eugene OR

Assignee:

Litton Systems, Inc. - Woodland Hills CA

International Classification:

G02B 110

US Classification:

359584

Abstract:

A mirror for reflecting a selected frequency of light includes a plurality of alternating quarter wavelength thick layers of two dielectric materials that are resistive to physical and chemical changes upon exposure to ultraviolet radiation coated upon a substrate. The materials have different refractive indices. The materials preferably are comprised of a mixture of alumina and tantala as the high refractive index layer and alumina as the low refractive index layer.