Device and method for coupling light of different wavelengths into a waveguide

US11435568B2 · kind B2 · utility

Assignee

• DR. JOHANNES HEIDENHAIN GMBH · DE

Inventors

• Wolfgang Holzapfel · Obing, DE
• Michael Kugler · Vestenbergsgreuth, DE
• Martin Roetzer · Traunreut, DE
• Marco Schade · Nordhausen, DE

Key dates

• Filing date: Dec 4, 2020
• Grant date: Sep 6, 2022
• Expiry date: Jan 22, 2041

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B2006/12152
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A device includes a grating coupler with a grating constant, two light sources, and a planar waveguide, which are configured to couple light with two different wavelengths λ1, λ2 into the waveguide. The waveguide has a waveguiding layer disposed adjacent to a substrate layer and a cover layer. The waveguiding layer has a thickness d and effective refractive indices of N(λk, jk), wherein λk is one of the wavelengths and jk is an order of a waveguide mode, wherein the coupled light of the wavelength λk has a coupling angle αk into the waveguide, and wherein an amount of difference between the coupling angles is a divergence angle Δα. Guiding of waveguide modes of the order jk>0 is possible for a wavelength of the coupled light. The waveguiding layer is arranged to couple the light via the grating coupler under a divergence angle of Δα<6.