Integrated optical polarizer with high extinstion ratio and low insertion loss, and improved method of fabrication thereof

US4789212A · kind A · utility

Assignee

• Amphenol Corporation · US

Inventors

• Julian P. G. Bristow · Lakeville, US
• Michael R. Keur · Niles, US
• Gregory J. Lukas · Wheaton, US
• Sriram S. Sriram · Naperville, US
• Albert Chin-Tang Wey · Westmont, US

Key dates

• Filing date: Dec 22, 1986
• Grant date: Dec 6, 1988
• Expiry date: Dec 22, 2006

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B6/126
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An optical polarizer is described in which a propagation layer, i.e., a titanium diffused light guiding region in a lithium niobate Z-cut crystal, is covered with a dielectric buffer layer of ZnO. The dielectric buffer layer is covered by a meal layer, typically aluminum, although gold or silver can be used. The thickness of the buffer is chosen so as to increase the attenuation of TM modes of radiation in the waveguide relative to TE modes. The buffer layer thickness can fall within a broad range and is not required to fall within a very precise range to achieve a peak level of attenuation.