Douglas L Blackburn

US Patent:

47099879, Dec 1, 1987

Filed:

Dec 10, 1985

Appl. No.:

6/807150

Inventors:

Douglas Blackburn - Damascus MD
Albert Feldman - Rockville MD
Nicholas Lagakos - Silver Spring MD

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

G02B 644

US Classification:

350 9634

Abstract:

Pressure and temperature insensitive optical fibers are produced using a Ta. sub. 2 O. sub. 5 based glass composition which has a high bulk modulus and a low thermal expansion coefficient. The glass composition can function as the cladding in the optical fiber or as a protective coating which surrounds the cladding thereby protecting the fiber from fluctuations in temperature and pressure.

US Patent:

52216462, Jun 22, 1993

Filed:

Jul 15, 1991

Appl. No.:

7/730144

Inventors:

Douglas H. Blackburn - Damascus MD
Craig Stone - San Jose CA
David C. Cranmer - Brookeville MD
Dale A. Kauffman - Frederick MD
James Grundl - Gaithersburg MD

Assignee:

The United States of America as represented by the Secretary of Commerce - Washington DC

International Classification:

C03C 3076

US Classification:

501 55

Abstract:

Neutron absorbing glass compositions comprise SiO. sub. 2,. sup. 6 Li. sub. 2 O and optionally Al. sub. 2 O. sub. 3. The compositions may further include PbO. The compositions provide neutron absorption without release of gamma rays.

US Patent:

53648196, Nov 15, 1994

Filed:

Apr 28, 1993

Appl. No.:

8/053287

Inventors:

James L. Dexter - Alexandria VA
David G. Cooper - Riva MD
Douglas H. Blackburn - Damascus MD
David C. Cranmer - Olney MD
Dale A. Kauffman - Frederick MD

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

C03C 332

US Classification:

501 45

Abstract:

A Faraday rotator glass composition based on a fluoride glass, phosphate glass, fluorophosphate glass or a mixture thereof is doped with a lanthanide in a concentration sufficient to provide a Verdet constant above at least 2870 deg/Tesla-meter [(1 min/cm-Oe). times. (1. 667. times. 10. sup. 4)=1 deg/Tesla-meter] and optical transmission above at least 50 percent in a 25 mm thick polished glass sample at least at one wavelength in the 200 to 400 nm wavelength region. The Faraday rotator glass also includes monovalent non-lanthanide cations such as Na, Li, K or mixtures thereof in a concentration sufficient to provide a Verdet constant above at least 2870 deg/Tesla-meter and optical transmission above at least 50 percent in a 25 mm thick polished glass sample at least at one wavelength in the 200 to 400 nm wavelength region. The Faraday rotator glass further includes a concentration of divalent or trivalent non-lanthanide cations such as Mg, Be, Ca, Al or mixtures thereof sufficient to provide surface flatness of at least 1/10 of the operating wavelength at 632. 8 nm.

Author:

Douglas Blackburn

ISBN #:

0898753538