Film confined to a frame having relative anisotropic expansion characteristics

US6160663A · kind A · utility

Assignee

• 3M INNOVATIVE PROPERTIES COMPANY · US

Inventors

• William W. Merrill · White Bear Lake, US
• John Christopher Harvey · New York, US
• Reney R. Langlois · River Falls, US
• Michael W. Mills · Cottage Grove, US
• Rosalind E. Peebles · Chicago, US
• Fred J. Roska · Woodbury, US

Key dates

• Filing date: Oct 1, 1998
• Grant date: Dec 12, 2000
• Expiry date: Oct 1, 2018

Classification

• Technology area (CPC G): Physics
• CPC primary: G02F2203/60
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An assembly comprising a film bounded by a frame, the film having a first thermal expansion coefficient along a first direction parallel to the film and a second thermal expansion coefficient along a second direction parallel to the film, wherein thermal expansion of the film compared to that of the frame is greater along the first direction than along the second direction, and wherein the film has a shape at an ambient reference temperature different from that of the frame, the shape of the film being selected to reduce clearance while allowing sufficient room between the film and the frame for thermal expansion in the first direction for temperatures up to a predetermined elevated reference temperature.