Optical: systems and elements – Lens – With lens casing
Reexamination Certificate
2002-10-15
2004-05-11
Mack, Ricky (Department: 2873)
Optical: systems and elements
Lens
With lens casing
C359S819000
Reexamination Certificate
active
06735023
ABSTRACT:
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to an optoelectronic module and to a method for its production. A preferred application area of the invention is that of low-cost optoelectronic modules that are coupled to Plastic Optical Fiber (POF) optical waveguides.
German Published, Non-Prosecuted Patent Application DE 199 09 242 A1, corresponding to U.S. Pat. No. 6,309,566 to Mueller, discloses an optoelectronic module and a method for its production in which a support with an optoelectronic transducer is positioned in a mold and surrounded with a translucent, moldable material. The moldable material in this case forms a molding that contains a functional surface serving for the coupling. The shaping of the functional surface takes place by a dead mold, which is shaped in a way corresponding to the functional surface and is removed once the moldable material has been introduced into the module housing.
A disadvantage of the prior art production method is that a dead mold is required for shaping the functional surface and this is a disposable part. A further disadvantage is that there is the risk of the functional surface formed by the moldable material in the molding being defectively produced. In particular, there is the risk of an air bubble being formed in the dead mold forming the functional surface during filling with the moldable material so that the functional surface is not formed as a converging lens and, instead, due to the air bubble, is formed as a diverging lens.
The problems described arise to an increased extent if a photodiode or a laser diode that has a smaller diameter in comparison with the component to be coupled on is used as the optoelectronic transducer. So, there is an especially high risk of an air bubble becoming lodged in the correspondingly small depressed formation of the dead mold and leading to the forming of a diverging lens instead of a converging lens.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide an optoelectronic module and method for its production that overcome the hereinafore-mentioned disadvantages of the heretofore-known devices and methods of this general type and that avoid the problems explained above and also make it possible to provide a precision-made coupling lens, in particular, even in the case of optoelectronic transducers of small diameter.
With the foregoing and other objects in view, there is provided, in accordance with the invention, an optoelectronic module, including an element, the element being at least one of a transmitting element and a receiving element, a support on which the element is disposed, a module housing defining an opening for introducing the support, the module housing having a coupling region for coupling a component thereat and an interior, a molding of a translucent, moldable material filling the interior of the module housing, and a separate coupling lens for coupling light between the element and the component, the lens disposed adjacent the molding one of in the coupling region and adjacent the coupling region.
Accordingly, in a first aspect of the invention, a coupling lens is disposed in the module housing in or just in front of the coupling region and adjacent to the molding. The coupling lens is formed as a separately produced part that, depending on the method of production used, is inserted into the module housing before or after the filling of the module housing with the molding material.
The coupling lens is, consequently, not formed by the molding but represents a separate part. By using a separately produced part as the coupling lens, it is ensured that the coupling lens has the desired light-shaping properties even in the case of small dimensions.
Preferably, the coupling lens is formed such that it completely closes the coupling region, in particular, toward the interior of the module housing. Such a feature has the advantage that the use of a dead mold or plug formed as a disposable part is superfluous because the module housing is already closed by the coupling lens.
In accordance with another feature of the invention, the coupling lens is accordingly inserted into the module housing before filling of the module housing with the moldable material. Insertion may, in such a case, take place from the inner side or else from the outer side. Preferably, the lens sealingly closes the coupling region with respect to the interior
In accordance with a further feature of the invention, preferably, the coupling lens is shaped such that it has a holding edge, which radially adjoins the light-shaping region of the lens and bears against the module housing in the transitional region to the coupling region. A seal-tight connection with the module housing preferably takes place in such a case by a positive engagement, with peripheral grooves, recesses, or other positively engaging areas being formed in the module housing and/or the holding edge of the coupling lens. The holding edge may be formed integrally with the light-shaping region or represent a separate support, serving for positioning and securing, onto which the light-shaping region, i.e., the actual converging lens, is placed.
In accordance with an added feature of the invention, the module housing has an inner side, the holding edge has an edge region and a peripheral recess in the edge region forming an inner projection and an outer covering region of the holding edge, the lens protrudes with the inner projection into the coupling region and peripherally bears against the coupling region, and the covering region bears against the inner side of the module housing.
In accordance with an additional feature of the invention, the holding edge has a side facing away from the interior of the module housing and forms, on the side, a stop for coupling the component thereon.
In accordance with yet another feature of the invention, the holding edge of the coupling lens is formed with a cranked offset. The periphery of the holding edge in such a case forms, in the direction of the coupling region, a stop for a component to be coupled. The stop is offset axially with respect to the lens vertex in the direction of the coupling region so that there is no risk of an optical waveguide introduced into the coupling region in an abutting coupling with the coupling lens coming directly into contact with the light-shaping region, and possibly damaging the latter thereby.
In accordance with yet a further feature of the invention, the lens is a double lens.
In accordance with yet an added feature of the invention, the molding forms, in the coupling region, a depressed formation that, during the filling of the module housing with the molding, is formed by a projection of a correspondingly shaped dead mold that is removed after filling, and the coupling lens is inserted into this depressed formation of the molding. Unlike in U.S. Pat. No. 6,309,566 to Mueller, the depressed formation does not in such a case form a coupling lens, but represents a receiving and positioning aid for a separately made coupling lens. The coupling lens is, preferably, adhesively bonded into the associated depressed formation of the molding.
In accordance with yet an additional feature of the invention, the element has a smaller diameter than the component.
In accordance with again another feature of the invention, the coupling region is a protruding connecting piece forming a socket for receiving the component.
With the objects of the invention in view, there is also provided an optoelectronic module, including an element, the element being at least one of a transmitting element and a receiving element, a support on which the element is disposed, a module housing defining an opening for introducing the support, the module housing having a coupling region for coupling a component thereat and an interior, and a molding of a translucent, moldable material filling the interior of the module housing, the molding having a functional surface with an outer contour formed during filling of the module housing with the molding by a d
Greenberg Laurence A.
Infineon - Technologies AG
Locher Ralph E.
Mack Ricky
Stemer Werner H.
LandOfFree
Optoelectronic module and method for its production does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Optoelectronic module and method for its production, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optoelectronic module and method for its production will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3206940