Encapsulated light source with coupled fiberguide

• US 4,296,998 A
• Filed: 12/17/1979
• Issued: 10/27/1981
• Est. Priority Date: 12/17/1979
• Status: Expired due to Term

• Current Assignee: Bell Telephone Laboratories, Inc. (Nokia Corporation)
• Original Assignee: Bell Telephone Laboratories, Inc. (Nokia Corporation)
• Inventors: Dufft, William H.
• Primary Examiner(s): Lee, John D.
• Application Number:
  US06/104,364
• Time in Patent Office: 680 Days
• Field of Search: 350/96.15, 350/96.17, 350/96.20, 350/96.21, 350/320, 250/227, 250/552, 357/17, 357/18, 357/30, 357/72, 357/74, 357/80, 357/81
• US Class Current: 385/91
• CPC Class Codes: G02B 6/4202 for coupling an active element with fibres without intermediate optical elements, e.g. fibres with plane ends, fibres with shaped ends, bundles
• CPC Class Codes: G02B 6/4238 Soldering
• CPC Class Codes: G02B 6/4248 Feed-through connections for the hermetical passage of fibres through a package wall see provisionally also G02B6/4428
• CPC Class Codes: G02B 6/4428 Penetrator systems in pressure-resistant devices

Abstract

A laser is coupled to an optical fiber in an hermetic encapsulation by locking a portion of the fiber near the laser in a body of solder. With the laser energized, the position of the optical fiber is adjusted within an aperture through the solder body to optimize the light output at the end of the fiber. The solder body then is heated to cause flow around the fiber and cooled to lock the fiber in position.

Claims

1. An encapsulated light source comprising a housing having walls, light generating means in the housing comprising a semiconductor light emitting device having a light output face, light transmitting means comprising a fiberguide penetrating a wall of the housing for transmitting light from the light emitting device to the exterior of the housing, a pedestal member within the housing having a top surface adjoining the light output face of the light emitting device, an unhoused body of low melting metal mounted on the top surface of the pedestal, the metal body having a portion of the fiberguide embedded therethrough to lock the fiberguide in position relative to the light output from the light emitting device.

2. The method of fabricating an encapsulated light source including a coupled optical fiberguide which is locked in position relative to the source light output, the method comprising the steps of,

(a) mounting a low-melting metal body in the encapsulation in close proximity to the light source, the body having an aperture therethrough several times larger than the diameter of the fiberguide,

(b) inserting a portion of the fiberguide through the aperture,

(c) energizing the light source to provide a light output,

(d) manipulating the fiberguide within the aperture in the X and Y direction while observing the light output from the fiberguide to determine the optimum position of the fiberguide relative to the light source,

(e) heating the body to a state sufficiently molten so that it flows into contact with the fiberguide portion and

(f) cooling the body to the solid state to fix the fiberguide in position relative to the light source.

3. The method in accordance with claim 2 in which the light source is a semiconductor junction laser.

4. The method in accordance with claim 2 in which a laser is used to heat the low-melting metal body.