Optical connector assembly

Abstract

A method and apparatus is disclosed for enabling a coupling of at least one optical fiber with an optoelectronic device. The apparatus comprises at least one v-groove for receiving at least one optical fiber. A first end of the apparatus is then polished at a predetermined angle in order to enable an optical coupling with the optoelectronic device.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This is the first application filed for the present invention. This application is related to commonly assigned co-pending applications filed herewith bearing agent docket numbers 16005-2US entitled “Optical Ferrule” and 16005-3US entitled “Encapsulated Optical Package”, the specifications of which are hereby incorporated by reference. TECHNICAL FIELD [0002] This invention relates to the field of optical connecting devices. More precisely, this invention relates to methods and apparatus for connecting optical fibers to optoelectronic devices. BACKGROUND OF THE INVENTION [0003] The optical coupling of light emitted, absorbed or altered by optoelectronic (OE) devices, such as photodetectors, light emitting diodes (LED's), lasers, and vertical cavity surface emitting lasers (VCSEL), with optical waveguides, such as optical fibers and planar waveguides, is well known in conventional photonics. One technique that is known involves cutting an...

AI Technical Summary

Benefits of technology

[0014] This invention relates to the optical coupling of light emitted, absorbed or altered by optoelectronic devices (such as photodetectors, light emitting diodes, lasers, vertical cavity surface emitting lasers (VCSEL), etc.) with optical waveguides (such as optical fibers, planar waveguides, etc.). The invention facilitates the coupling procedure by using mechanical assemblies to hold the waveguides in contact with the optoelectronic devices. These assemblies do not require any other coupling agent, such as lenses, but must be sufficiently close in order to maximize the coupling efficiency into (or out of) the waveguide (optical fiber). Both assemblies are particularly amenable to a one-step alignment process involving the planar-on-planar (or stacked) 2-D alignment of the waveguide assembly with an optoelectronic assembly. The assemblies are stacked on top of each other and viewed from above to simultaneously observe features on both the waveguide assembly and the optoelectronic assembly. The alignment process involves sliding the two assemblies (waveguide assembly and optoelectronic assembly) with respect to each other on their co-incident 2-D surfaces. This procedure can be done passively (without energizing the optoelectronic assembly), and requires only one alignment step to be performed. This is contrary to other methods described in the prior art that use mechanical constraints, such as extra grooves, stop-walls, stand-offs, precision machining or precise pick-and-place methods to align waveguides to optoelectronic devices. It also supercedes older methods that rely on large optoelectronic devices to overcome slight misalignments of the optical fiber.

[0015] The essential aspect of the waveguide assembly described below is the 45-degree bevel at the tips of the waveguides (optical fiber). This feature allows for side-coupling of light into the core of the waveguide (optical fiber) by using the 45-degree bevel as a mirror surface. The light is initially directed at 90-degrees to the longitudinal direction of the optical fiber and travels through the cladding towards the center of the beveled tip. Total internal reflection at the 45-degree beveled tip forces the light to reflect at 90-degrees and couple along the longitudinal axis of the optical fiber. A metallic reflection coating can be applied to the beveled tip with an appropriate metal to enhance the coupling into the optical fiber. One of the earliest references of the 45-degree beveling of optical fiber can be found in U.S. Pat. No. 4,130,343 granted Dec. 19, 1978. In this patent, a single optical fiber is beveled at 45-degrees and placed in-contact over a single optoelectronic device. The embodiment described in this document uses this now common approach but improves the alignment method.

Problems solved by technology

This method allows more conventional packaging and reduces the alignment tolerance because the length of the optical fiber is essentially laid over the flat surface of the PCB.

The alignment procedures for these types of assemblies are complicated.

These methods typically involve micro-solder ball re-flow, flip-chip alignment and / or precisely machined parts, which require significant resources and materials.

This technique may be adequate for large area optoelectronics, but would not be a suitable alignment methodology for small devices such as VCSELs.

This completely rules-out a VCSEL chip since the vertical cavity laser would be damaged if bonded up-side-down, not to mention that the wirebond connections are made on the same surface as the vertical cavity laser and it would be physically impossible to wirebond to the VCSEL chip in such an orientation.

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