Optical assembly

Details Optical assembly Optical assembly

2001-03-01

2003-02-25

Kim, Ellen E. (Department: 2874)

Optical waveguides

With disengagable mechanical connector

Optical fiber to a nonfiber optical device connector

C285S021100, C219S538000, C156S060000

Reexamination Certificate

active

06524018

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an optical assembly and more specifically to a transceiver assembly which is used for receiving or transmitting optical signals.
2. The Related Art
An optical transceiver module is an important part of an optical communication system. The optical transceiver requires an optical assembly for receiving or transmitting optical signals. The optical assembly consists of many parts which must have precise relative orientation with respect to each other. This complicates the assembling process of the optical assembly. Thus a variety of methods have been developed for manufacturing the optical assembly.
Heat cured epoxy is one of the methods for assembling the optical assembly. The optical assembly includes a support member and a cap member, wherein the support member has a first surface, and the cap member has a corresponding and matching second surface. To assemble, the cap member and the support member are held by an aligning apparatus which is adjusted to have the members in perfect alignment. The members are brought together with the first surface and the second surface mating each other. Heat cured epoxy is applied between the surfaces. Heat is then applied to cure the epoxy by placing the aligning apparatus and the members in a heating oven.
Since it is difficult to have a uniform heating result on the members, the members may displace with respect to each other during the heating process, deteriorating the alignment between the members. Furthermore, unexpected contacts or impacts may occur on the aligning apparatus when it is moved into the heating oven. Such contact or impact may cause misalignment between the members.
Besides the above drawbacks, this method is not suitable for single-mode fiber transmission system. A single-mode optic fiber has a core with a diameter of only 6-10 &mgr;m. An offset of 0.5 &mgr;m between the members will significantly affect the system.
U.S. Pat. No. 4,969,702 (See
FIG. 1
) teaches a different method. As shown in
FIG. 1
, a laser diode
12
is positioned in a support member
14
. A focusing member
16
, such as a gradient index lens having a planar surface and an opposing convex surface, is positioned with respect to he laser diode
12
such that an output beam from the laser diode
12
passes through the lens
16
. A cap member
18
which defines an aperture
22
for receiving a ferrule
26
in which a fiber optic cable
24
is retained is attached to the support member
4
with a mounting surface
20
of the cap member
18
in contact with the support member
14
. The relative position between the cap member
18
and the support member
14
is adjusted by aligning apparatus to have the aperture
22
of cap member
18
in alignment with the lens
16
. A UV (ultraviolet) cured epoxy is applied between the cap member and the support member so that when the assembly is exposed to UV light, the epoxy is cured and thus fixes the cap member to the support member.
To allow the epoxy to be exposed to the UV, at least one of the members must be transparent. This limits the selection of the material. Furthermore, to avoid blocking UV light, a special design of the aligning apparatus is required. This increases the cost of design and manufacture.
Another method of assembling the optical assembly is disclosed in U.S. Pat. No. 5,073,047 (See FIG.
2
). The optical assembly shown in
FIG. 2
includes a light source
15
retained in a holder
19
, a housing
17
and a receptacle
1
. The holder
19
is fusion-welded to the housing
17
by a laser beam. A positional adjustment is performed to align the housing
17
with respect to the receptacle
1
. The aligned housing
17
and receptacle
1
are also solidly welded together by means of a laser beam. The cost for performing laser welding is high.
Instant glue is also often employed to attach parts of an optic assembly together due to its low cost. After a positional adjustment is performed between a support member and a cap member by means of an aligning apparatus, the instant glue is applied on the interface between the cap member and the support member. The members are fixed together when the instant glue is cured. The method suffers a non-uniform curing result of the glue because the glue is cured by being contacted with steam and it is hard to control the distribution of steam in a given space. This may cause displacements of the members with respect to each other, resulting in misalignment.
In view of the above, an optical assembly which is assembled easily and has a precise relative orientation is required.
SUMMARY OF THE INVENTION
In view of above described problems of the prior art, it is an object of the present invention to provide an optical assembly which can be assembled easily and effectively.
Another object of the present invention is to provide an optical assembly having a precise relative orientation.
To achieve the above objects, the present invention provides a method of assembling an optical assembly using a heat cured epoxy. The optical assembly includes a support member and a receptacle. The support member has a first junction surface and the receptacle has a second junction surface. An electrical heating wire is positioned in the support member proximate the first surface. After having the members in perfect alignment, a heat cured epoxy is applied between the first and second junction surface. The epoxy is cured by heat generated by the heating wire thereby securing the receptacle to the support member.


REFERENCES:
patent: 4684417 (1987-08-01), Grandclement
patent: 5150922 (1992-09-01), Nakashiba et al.
patent: 5255942 (1993-10-01), Kenworthy
patent: 6137926 (2000-10-01), Maynard
patent: 6392208 (2002-05-01), Arx

Affiliated with

Also associated with

Rating

Optical assembly 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 assembly, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical assembly will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3128682