Charles F Houghton

US Patent:

20030231390, Dec 18, 2003

Filed:

Mar 14, 2003

Appl. No.:

10/389706

Inventors:

Steven Wein - Sudbury MA, US
David Korwan - Westford MA, US
Charles Houghton - Manchester MA, US
James Targove - Sudbury MA, US

International Classification:

G02B005/30
G02B027/28

US Classification:

359/495000

Abstract:

An athermalized delay line having two optical paths whose difference in optical path length is thermally insensitive. Each optical path typically includes a reflecting quarterwave plate, each path being fed by the output from a polarizing beamsplitter. The delay line is suitable for incorporation into a PMD compensator having at least one compensation stage formed from a polarization controller and an athermalized delay line.

US Patent:

50023780, Mar 26, 1991

Filed:

Aug 3, 1990

Appl. No.:

7/563025

Inventors:

Joseph M. Colarusso - Nashua NH
Charles D. Houghton - Manchester MA

Assignee:

Litton Systems, Inc. - Lexington MA

International Classification:

G02B 508

US Classification:

350610

Abstract:

A lightweight cooled mirror is disclosed in which cooling of the mirror's reflecting surface is provided by a two-phase fluid contained in an enclosed chamber behind the reflecting surface. The chamber includes an evaporator section in contact with the reflecting surface and a condenser section spaced apart from the reflecting section. The fluid is capable of existing in both liquid and gaseous states. When in a liquid state, the fluid can absorb heat from the reflecting surface which transforms the liquid into a gas. The gas is transported away from the reflecting surface to a section in the enclosed chamber where it gives up the absorbed heat by condensation and is converted back into a liquid which is reused to absorb additional heat from the reflecting surface. The liquid is transported back toward the reflecting surface by a wicking action to complete the closed loop fluid flow system.