1987-01-23
1989-06-06
Sikes, William L.
350 9620, G02B 632, G02B 636
Patent
active
048366331
DESCRIPTION:
BRIEF SUMMARY
This invention relates to optical connecting arrangements providing for the precise optical alignment of optical fibres relative to the active or operational surfaces of optical devices (e.g. light generating devices, such as light emitting diodes and lasers, light responsive devices, such as photo-diodes and photo-transistors or light modulating devices).
According to the present invention there is provided an optical connecting arrangement between an optical device (e.g. light generating or light responsive device) and an optical fibre in which the optical device is mounted with positional precision on a substrate which is fabricated for locating one end of a so-called GRIN rod lens in precise optical alignment with the active surface of the optical device mounted on said substrate and in which the other end of the same GRIN rod lens or the corresponding end of a further GRIN lens coupled to it has the optical fibre optically coupled thereto in optical alignment.
In carrying out the present invention the substrate on which the optical device is mounted may be fabricated with a relatively deep cylindrical well for receiving the end of the aforesaid GRIN rod lens which is preferably enclosed within a close fitting ferrule (e.g. metal) the end of which is a precision fit in the cylindrical well of the substrate and may be metallically or otherwise securely bonded to the substrate.
The relatively deep well of the substrate in the case of many substrate materials, including silicon, may be produced by well-known etching techniques (e.g. photo-lithographic etching, sputter etching, reactive ion etching and chemical etching) according to the particular material employed for the substrate.
For the purpose of attaching an optical device to the substrate so that the device is accurately located relative to the position of the end of the GRIN rod lens the device may be provided with an array or pattern of accurately positioned metallic bonding pads arranged to be bonded to correspondingly positioned pads or equivalent on the substrate.
To facilitate the bonding of the optical device to the substrate the metallic bonding pads on the substrate and/or the optical device may be coated with solder or solder bumps provided and so-called solder reflow self-aligning techniques then employed to actually effect bonding of the device to the substrate. The manner in which the metallic bonding pads may be formed on the substrate and the optical device and the solder reflow techniques are fully described in our co-pending patent application No. (84 08877). The solder flow self-aligning bonding techniques eliminate the need for costly manual alignment techniques for the location of the optical devices relative to the substrates.
The substrate material is preferably silicon which is readily available at moderate cost and which has good thermal conductivity thereby enabling the substrate to function as an effective heat sink structure. Moreover, processing technology (e.g. etching, doping, metallisation etc) associated with silicon is already well developed and, moreover, the semiconductor properties may be used to provide for example an integral substrate driver transistor for driving a light emitting diode mounted on the substrate as aforesaid.
The present invention enables optical devices mounted on substrates to be optically aligned with optical fibres in a highly controlled and repeatable process suitable for large volume manufacture.
By way of example a number of embodiments of the present invention will now be described with reference to the accompanying drawings in which:
FIG. 1 is a part cross-sectional side view of an optical connecting arrangement according to the present invention;
FIG. 2 is a cross-sectional enlarged view of the substrate and associated optical device forming part of the optical connecting arrangement shown in FIG. 1;
FIG. 3 shows an underneath view of an exemplary optical device of FIG. 2;
FIG. 4 shows a plan view of a fragment of an exemplary substrate of FIG. 2;
FIG. 5 shows a plurality of substrate
REFERENCES:
patent: 4186995 (1980-02-01), Schumacher
patent: 4307934 (1981-12-01), Palmer
patent: 4357072 (1982-11-01), Goodfellow et al.
patent: 4383731 (1983-05-01), Simon et al.
patent: 4427879 (1984-01-01), Becher et al.
patent: 4575194 (1986-03-01), Strefer et al.
patent: 4653847 (1987-03-01), Berg et al.
patent: 4658130 (1987-04-01), Durbin
"A GaAlAs Edge Emitting LED with a Lunched Power in Excess of 1W", by Davies, Standard Telecommunications Lab: Ltd. Sep. 1980.
Carter Andrew C.
Davis Richard
Morgan Peter J.
Randle Frederick A.
Plessey Overseas Limited
Sikes William L.
Ullah Akm E.
LandOfFree
Optical connecting arrangements does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Optical connecting arrangements, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical connecting arrangements will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-35745