Patent ID: 6088495
Filing Date: 2000-07-11
Classification: G02B,H04N

Abstract:
An optical coupler, comprising:(a) a first optical waveguide including a guide portion, said guide portion including a coupling section having a certain length;(b) a second optical waveguide including a guide portion, said guide portion including a coupling section substantially parallel to said coupling section of said guide portion of said first optical waveguide, said coupling section of said guide portion of said second optical waveguide having a certain length;(c) an optical medium intervening between said coupling sections, thereby providing said coupling sections with a certain beat length, with respect to monochromatic light transmitted by said waveguides, that is longer than a larger of said lengths of said coupling sections; and(d) a coupling enhancement mechanism operative to reduce said beat length to below a smaller of said lengths of said coupling sections by coupling at least one mode confined to said coupling section of said first waveguide with at least one mode confined to said coupling section of said second waveguide via at least one mode common to both of said coupling sections.