Structure for shielding stray light in optical waveguide module
AssigneeNEC Corporation
InventorYasuhiro Fukutomi
Life of this patent
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Abstract
A structure for shielding a stray light in an optical waveguide module is composed of an optical waveguide substrate supported in an optical waveguide module package, an optical waveguide formed on the optical waveguide substrate, a LD mounted on the optical waveguide substrate, an optical fiber-placement section formed on the optical waveguide substrate, an optical fiber situated on the optical fiber-placement section, a WDM filter formed on the optical waveguide substrate, a PD-mounting carrier situated behind the WDM filter, a PD mounted on the PD-mounting carrier, a metallic layer evaporated on the WDM filter, and a pin hole formed on the metallic layer at nearly a center thereof.
Claims6
A structure for shielding a stray light in an optical waveguide module, comprising:
- an optical waveguide substrate supported in an optical waveguide module package,
- a laser diode (LD, hereinafter) which is mounted on said optical waveguide substrate and emits a first signal light,
- an optical waveguide which is formed on said optical waveguide substrate and propagates a part of said first signal light,
- a wavelength division multiplexing (WDM, hereinafter) filter which is formed on said optical waveguide substrate,
- an optical fiber which is situated on said optical waveguide substrate and transmits said part of said first signal light to an optical transmission line,
- a photodiode (PD, hereinafter) for receiving a second signal light which is propagated through said optical transmission line and transmitted through said WDM filter via said optical waveguide, and
- a metallic layer which is evaporated on a surface of said WDM filter and provided with a pin hole for transmitting said second signal light to said PD via said WDM filter,
- wherein a remaining part of said first signal light (a stray light, hereinafter) which is not optically coupled with said optical waveguide is reflected by said metallic layer so that said stray light is prevented from being coupled with said PD.
A structure for shielding a stray light in an optical waveguide module, comprising:
- an optical waveguide substrate supported in an optical waveguide module package,
- a LD which is mounted on said optical waveguide substrate and emits a first signal light,
- an optical waveguide which is formed on said optical waveguide substrate and propagates a part of said first signal light,
- a WDM filter which is formed on said optical waveguide substrate,
- an optical fiber which is situated on said optical waveguide substrate and transmits said part of said first signal light to an optical transmission line,
- a photodiode for receiving a second signal light which is propagated through said optical transmission line and transmitted through said WDM filter via said optical waveguide, and
- a plate which is stuck to a surface of said WDM filter, does not transmit said first and second signal lights but reflect them, and is provided with a pin hole for transmitting said second signal light to said PD via said WDM filter,
- wherein a remaining part of said first signal light which is not optically coupled with said optical waveguide is reflected by said plate so that said stray light is prevented from being coupled with said PD.
Dependencies are inferred from the claim text.