US 4,789,212 A · Integrated optical polarizer with high extinstion ratio and low insertion loss, and improved method of fabrication thereof

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.

Claims14

Dependent claims

An integrated optical circuit device for polarizing light comprising:

an in-diffused channel light guiding region in a substrate comprising LiNbO.sub.3 or LiTaO.sub.3, said substrate being a Y-cut or Z-cut LiNbO.sub.3 or LiTaO.sub.3 crystal with said light guiding region having been defined by diffusing titanium into the crystal;
a dielectric layer of ZnO overlying the light guiding region and adhered to the substrate;
an aluminum layer overlying the ZnO layer and adhered thereto;
and said ZnO and aluminum layers being of a thickness effective to cause substantial attenuation of TM like modes of light being transmitted through the light guiding region while minimizing attenuation for TE like modes.

1 more element

Dependencies are inferred from the claim text.

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

Life of this patent

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

Life of this patent

Abstract

Claims14