Abstract: A packaged optical device with an integrated optical component mounted within a housing which includes an end wall confronting a cheek of the component to which an optical fiber is to be connected to communicate with an internal structure of the component. The wall has an aperture in which is mounted an elongate rigid ferrule through which the optical fiber extends, so that the end faces of the fibre and ferrule are co-planar. After the ferrule has been manipulated externally of the housing to align the fibre with the component structure, the ferrule is secured in position by a UV setting adhesive. The end face of the ferrule may be adhered to the cheek of the component to maintain the alignment.

Abstract: An optical fiber coupler and its method of use are disclosed. In the coupler a centrally located lens is disposed between the ends of the source and outlet optical fibers, the fibers themselves are formed into the most spacing filling configuration at their ends adjacent the lens, and the lens and fiber ends are secured with an adhesive. The lens, fibers and adhesive will all have substantially equivalent indices of refraction so that there is no excessive light attenuation through the lens and adhesive layers. The optical fibers may be glass or polymer, be single or multiple mode, and have uniform, step or graded refractive indices. A wide variety of combinations of fiber bundles, from single fibers to bundles of up to 128 or more fibers, can be coupled through this device. In its method of use aspect, the received fibers are inserted into the sleeve and adhered to the lens with the adhesive, while venting trapped air and excess adhesive.

Abstract: The coupling of optical signals to the active region of a FET having a wide source to drain spacing via an optical fiber and material having an index of refraction matching that of the fiber or the FET so as to increase the locking range when the FET is part of an oscillator circuit or to increase the change in the electrical gain of the FET caused by a change in the optical energy if the FET is an amplifier.

Abstract: Photodynamic therapy apparatus providing improved light distribution with an end fitting for use with clad optical fibers, which apparatus cooperates with an unclad stripped terminal end of the optical fiber that is inwardly tapered towards its end such that light scattering media disposed between a glass tube surrounding at least the tapered portion of the optical fiber provides improved and predictable light distribution, the media being suitably cured to a rigid relationship thereby to continuously provide improved light distribution.

Abstract: An optical fiber reinforcing structure and method of manufacture thereof for reinforcing an optical fiber having a cladding portion removed to expose a fiber core portion. The optical fiber with the fiber core portion is placed in a longitudinal groove of a reinforcing member. The optical fiber is fixed to the reinforcing member at the ends of the longitudinal groove using an adhesive. A cover is then fixed to the reinforcing member to hermetically seal the optical fiber within the longitudinal groove. The reinforcing structure of the present invention prevents environmental conditions from adversely affecting the optical characteristics of the optical fiber.

Abstract: A temperature probe includes a sensor material optically communicating with a waveguide, and a sheath having a sheath coefficient of thermal expansion substantially matched to a thermal expansion coefficient of the waveguide. The waveguide has first and second ends secured proximate corresponding sheath ends. In another aspect of the invention, waveguide ends are secured near the sheath ends, the sheath is bent at one or more locations so that it is noncylindrical, and a midsection of the waveguide is loosely held within the bent sheath. In still another aspect of the invention, a metallic tube with the sensor material disposed therein is secured to the waveguide by direct attachment to a metallic coating on the waveguide.

Abstract: A broadband optical fiber coupler comprising at least three continuous optical fibers fused at a region of coupling, at least one of the continuous optical fibers being dissimilar to others of the continuous optical fibers in the region of coupling, the region of coupling being of a length and the dissimilarity being of a degree to provide broadband response over a predetermined range of wavelengths. A related method for making a broadband optical fiber coupler is also disclosed.

Abstract: An integrated optical coupler comprises a substrate with fiber-aligning grooves and waveguiding channels and a covering with complementary grooves and, optionally, channels. These couplers can be made from reproducible masters and electroplated molds made from those masters.

Abstract: A method for internal laser welding of metallized optical components for attachment of optical fibers which comprises the steps of: milling a "V" groove in one end face of a fiber carrier; aligning an optical fiber in the "V" groove; polishing end faces of an integrated optics chip and the fiber carrier assembly; depositing chromium layers on integrated optics chip and the fiber carrier assembly; depositing eutectic alloy on chromium layers; optically aligning the optical fiber and a wave guide in the integrated optics chip; and applying a pulse laser beam for an internal laser weld between the end face of the integrated optics chip and the end face of the fiber carrier assembly.

Abstract: An improvement is proposed for decreasing the variation in the coupling ratio of an optical fiber coupler after a heat shock test. In an optical fiber coupler which is an elongated intergral body formed by fusing a plural number of optical fibers side-by-side consisting of two straightly columnar parts and a biconical part therebetween formed by drawing and adhesively bonded to a reinforcing base with a coating layer of an adhesive therebetween, the improvement can be achieved by limiting the zone where the coating layer of an adhesive to the surface of each of the straightly columnar parts within a range from the boundary between the straightly columnar part and the biconical part to a point 8 mm apart from the boundary.

Abstract: A guided-wave circuit module includes a guided-wave circuit chip having an input waveguide part and an output waveguide part at the ends thereof, a guided-wave circuit part having a predetermined function and positioned between the input waveguide part and the output waveguide part; and a holder for supporting the guided-wave circuit chip, wherein the guided-wave circuit part of the guided-wave circuit chip does not come in contact with the chip holder; at least part of the input and output waveguide parts of the guided-wave circuit chip is fixed to the holder with a fixing agent; and the packaged chip does not have a warp which leads to deterioration of characteristics. A fixing agent having a high hardness is applied to the periphery of the endfaces of the input and output waveguide parts of the guided-wave circuit module and to the periphery of the fiber endfaces of the optical fiber array connected to the module.

Abstract: An optical fiber coupler having a crosstalk characteristic of at least 18 dB. The optical fiber coupler includes a plurality of optical fibers. A length of glass in the optical fibers is exposed by removing the covering. The glass lengths are fused together and extended, during which time the fibers are twisted and subjected to a tension. The twisted fibers are then fixed to a protecting member while the tension is sustained.

Abstract: The first process for producing an optical fiber coupler includes a first step wherein at least one of the optical fibers to be used is stripped of the coating, a second step in which the bare portion of that optical fiber is heated for a predetermined time to diffuse the dopants, a third step wherein the other optical fibers which have not been heat-treated are stripped of their coating, a fourth step in which the bare portions of all the optical fibers are heated as they are brought into intimate contact, thereby forming a unitary portion, and a fifth step wherein the unitary portion is drawn via heating to form the coupling portion of an optical fiber coupler.

Abstract: A permanent optical fiber connector which makes it possible to connect and fix optical fibers (A) in some seconds. This connector comprises a base part (B) including a base body (4) made of a material of low expansion coefficient having a pair of opposed locking elements (7) and one or more capillary tubes (5) bonded to the base body and having an inner diameter slightly greater than the cladding of an optical fiber, and an optical fiber pressing part (C) including a pressing body (21) made of a material of low expansion coefficient and adapted to fit between the locking elements (7) of the base body to be embraced thereby and elastic bodies (22) attached to the lower surface of the pressing body, said pressing body (21) being embraced between the locking elements (7) of the base body, whereby the optical fiber pressing part (C) presses the covers (3) and optical fiber bodies (2) of the optical fibers (A) against the base part (B) to fix them to the latter.

Abstract: A method of attaching a Gradient Index (GRIN) lens to an optical fibre in the course of making an optical instrument for use at a working distance. The method is especially suitable for making an optical instrument with an extended working distance. In the method, a test object, a GRIN lens, and an optical fibre are provided. The GRIN lens is placed at the working distance from the test object, and is axially aligned with the test object. The optical fibre is placed adjacent to, and axially aligned with, the GRIN lens to form an image of the test object at the proximal face of the optical fibre. The distal face of the optical fibre is placed adjacent to the proximal face of the GRIN lens. At least one of the GRIN lens and the optical fibre is moved axially with respect to the other until the image of the test object is in focus. This determines an optimum axial spacing between the GRIN lens and the optical fibre.

Abstract: An achromatic fiber optic coupler of the type wherein three single-mode optical fibers are fused together along a portion of the lengths thereof to form a coupling region. Each fiber includes a core and a cladding, the lowest refractive index of the fiber claddings being n.sub.2. The fibers are disposed in a triangular array in the coupling region. A matrix glass body of refractive index n.sub.3 surrounds the coupling region, n.sub.3 being lower than n.sub.2 by such an amount that the value of .DELTA..sub.2-3 is less than 0.125%, wherein .DELTA..sub.2-3 equals (n.sub.2.sup.2' -n.sub.3.sup.2)/2n.sub.2.sup.2.

Abstract: The invention features a fiber optic coupler package including a rigid substrate and at least two side-by-side optical fibers joined in a coupler region. The substrate has a coefficient of thermal expansion substantially matched to that of the fibers. Each fiber extends axially to opposite sides of the coupler region to a primary and secondary regions of fixation, at each side of the coupler region. In the primary region of fixation, each fiber is separately bonded in close proximity to a rigid mounting surface of the substrate using a small amount of adhesive contiguously disposed on opposite sides of the line of tangency formed by the fiber and the mounting surface. The adhesive is distributed to form a pair of substantially identical masses with mirror symmetry relative to a plane defined by the central fiber axis and the line of tangency.

Abstract: The basic embodiment of the present invention comprises an optical fiber having cores and a claddings, and core-extensions, wherein the individual core-extensions are built onto the core end facets in a shape of the diverging horn-like structure, with the sectional area increasing gradually as the individual core-extensions extend farther away from the core end facets to merge together and form a common core-extension for light mixing and coupling. The core-extension may be made of a photo-reactive material to be shaped after the diverging radiation pattern of light emitted from the core end facets.

Abstract: A method of and apparatus for manufacturing and evaluating an optical fiber coupler in which the optical fibers are heated so that they are conjoined together through fusion and elongated to constitute the tapered portion of the optical fiber coupler, and characterized in that the tapered portion is housed and secured in a protective casing or the like as the portion remains positively twisted after the fusion conjoining and elongation of the fibers.

Abstract: An achromatic fiber optic coupler of the type wherein a plurality of single-mode optical fibers, each having a core and a cladding, are fused together along a portion of the lengths thereof to form a coupling region. The propagation constants of the fibers are preferably equal; however if the fiber claddings have different refractive indices, the lowest cladding refractive index is n.sub.2. A matrix glass body of refractive index n.sub.3 surrounds the coupling region, n.sub.3 being lower than n.sub.2 by such an amount that the value of .DELTA..sub.2-3 is less than 0.125%, wherein .DELTA..sub.2-3 equals (n.sub.2.sup.2- n.sub.3.sup.2)2n.sub.2.sup.2.

Abstract: An optical fiber directional coupler housing having a primary protective body substantially formed as a rectangular block with a receiving space therein. A slot in the primary protective body provides the receiving space therein. The coupled portion of the coupler to be housed is positioned in the receiving space. A resilient support material having an index of refraction less than that of the coupled portion extends into the receiving space extending between the coupled portion of the coupler which it also at least partially surrounds and the primary protective body. Plugs are typically provided at the ends of the protective body to secure the optical fibers extending from the coupled portion to the body. A heat shrinkable tubing is used as a jacket which encompasses and extends beyond the primary body.

Abstract: The invention provides an optical-coupler reinforcing member for fixing and reinforcing a fiber-coupler body and a method of performing the reinforcing. The reinforcing member includes heat-shrinkage tubes which are shrunk by heating, and a hollow protection pipe provided in the heat-shrinkage tubes. Cylindrical heat-fusible adhesive members are provided on opposite ends of the protection pipe, and heating is made such that a fusing portion of an optical-fiber coupler body is inserted through the reinforcing member so that the heat-fusible adhesive members and the heat-shrinkage tubes are shrunk by heating to thereby fix and reinforce the optical coupler body.

Abstract: Apparatus for routing optical fiber comprises an elongated manipulator (20, FIG. 2) having a vertical axis which can be controlled to move in an X-Y plane and in the .theta. direction around its vertical axis. A rotatable wheel (21) is mounted on a free end of the manipulator, and a reel (19) containing optical fiber (17) is mounted on one side of the manipulator. The fiber is threaded over a peripheral portion of the wheel and the wheel presses the fiber against an adhesive-coated surface of a substrate (18) to cause it to adhere to the coated surface. The manipulator is then moved in a direction parallel to the flat surface at an appropriate speed and direction to cause the wheel to rotate and to exert tension on the optical fiber. The tension causes additional optical fiber to unwind from the reel and to be fed to the wheel for adherence to the coated surface, thereby to form a continuous optical fiber portion extending along, and adhered to, the coated surface.

Abstract: Automatic alignment of an optical waveguide to a ridge waveguide laser is accomplished by transferring the ridge structure of the laser to a substrate by etching a mirror groove. The transferred ridge structure serves as a base for the deposition of waveguide layers. The thickness of the waveguide layers are controlled during the deposition such that the waveguide core is laterally and vertically aligned to the lasing active layer of the laser structure.

Abstract: An optical fiber tip for use in a laser delivery system comprising a distal end of an optical fiber having an exposed cylindrical core. A flat elliptical surface is formed across a distal end of said cylindrical core and intersects a center line of said cylindrical core at a predetermined angle. In one embodiment, a reflective coating is deposited on said flat elliptical surface such that a laser beam carried by said fiber will be reflected by said reflective coating. In another embodiment, said flat elliptical surface intersects said center line of said cylindrical core at an angle exceeding a critical angle necessary for said flat elliptical surface to totally reflect a laser beam carried by said optical fiber.

Abstract: A fiber optic coupler is formed by inserting a plurality of optical fibers into the longitudinal bore of a glass tube so that at least a portion of each fiber extends from at least one end of the tube. The midregion of the tube is collapsed onto the fibers, uncollapsed bore portions remaining at the tube end regions. Each bore portion is connected to the tube end surface by a funnel that facilitates the fiber insertion step. The central portion of the midregion is stretched to reduce the diameter thereof. In a first embodiment, glue is applied to the funnel. Before the glue is cured, a sufficient period of time is allowed to elapse to permit said glue to flow by capillary action between the fibers and the adjacent portion of the wall of the bore portion. The glue flows at least 3 mm into the bore portion beyond the bottom of the funnel. The glue that flows by capillary action fails to completely surround the fibers with glue. The glue is then cured.

Abstract: An overclad fiber optic coupler of the type wherein a plurality of optical optical fibers, each having a core and a cladding, are fused together along a portion of the lengths thereof to form a coupling region. Surrounding the coupling region is a matrix glass body of refractive index n3 which is lower than the fiber cladding refractive index n.sub.2. The body has an inner region adjacent the optical fibers, an outer region having a radius greater than that of the inner region, and a transition region between the inner and outer regions. The softening point temperature of the inner region is greater than that of the outer region. The coupler exhibits both low polarization dependent loss and low excess loss.

Abstract: A fiber optic coupler is formed by providing a glass tube having a longitudinal bore and first and second funnels connecting the bore to the ends of the tube. The protective coating is stripped from the central portion of two optical fibers. The first and second fibers are threaded into the tube bore until the uncoated portions thereof are located within the bore. The protective coating of only one of the fibers extends into the first end of the bore, and the protective coating or only one of the fibers extends into the second end of the bore. The fibers extend beyond the tube ends. The bore diameter is just slightly larger than the sum of the diameter of the first fiber and the diameter of the coating of the second fiber. The resultant tight fit of the fibers in the tube promotes the retention the fibers in parallel alignment during the subsequent tube collapse step. The midregion of the tube is heated, collapsed about the fibers, and drawn to form a coupling region.

Abstract: A microlens assembly for use with an optical fiber or fiber bundle that requires no crimping or mechanical distortion of the optical fiber. The microlens assembly has a front lens mounting portion and a rear portion. The rear portion is a cylindrical tube which is bonded to the sheath and cladding of the optical fiber or fiber bundle by means of suitable adhesive. The front lens mounting portion which houses the output lens is also tubular, having an inner diameter greater than the outer diameter of the rear portion. The front lens mounting portion is slid over the rear portion until the desired distribution of light emanating from the lens is achieved. The front lens mounting portion is then locked into position by bonding it to the rear portion by means of an appropriate adhesive. The adhesives are stable at high temperature and have an index of refractions suitable for preventing refractive loss of light from the lateral walls of the fiber core.

Abstract: A light coupling arrangement for efficiently coupling a light source to a light distribution arrangement includes a solid optical coupling device constructed of a light transmissive material and configured in an essentially planar manner such that the length and width dimensions are significantly greater than the depth dimension. An aperture is formed on at least one side along the equatorial surface of the optical coupling device and allows connection to the light distribution arrangement. A bore, formed in the optical coupling device and having a flat polished surface, houses the light source in a manner such that the optical coupling device can act as a heat sink for the light source.

Abstract: A bundle (12) of optical fibers (13) is fixed in a matrix array by apertures in a guiding plate (14) and a securing plate (15). The apertures (18) in the guiding plate are larger than those in the securing plate and the securing plate apertures (17) are funnel-shaped to aid in insertion of the fibers. Each row of optical fibers may be inserted simultaneously by mounting the row on a uniquely designed vacuum holder (26).

Abstract: An integrated optical component comprising at least one waveguide integrated into a substrate and connected to the end of an optical fiber which is attached to the substrate at said fiber end and in a region separated from said fiber end by a first drop of adhesive and a second drop of adhesive, respectively. The adhesive product which constitutes the first drop has a glass transition temperature located in a predetermined operating temperature range of the component, while the adhesive product which constitutes the second drop has a glass transition temperature located generally above this operating temperature range, thereby assuring the absorption of differential expansions in such a way as to maintain the optical continuity of the fiber/waveguide attachment and the mechanical strength of the fiber/substrate attachment.

Abstract: A circuit arrangement is provided for allowing the bidirectional exchange of received and transmitted signals over a single monomodal optical fiber. The light transmitter (usually a laser or a LED), the receiver of optical signals and an optical system suitable for directing the optical signal to be transmitted to the monomodal optical fiber ad for directing the optical signal from the monomodal optical fiber to the receiver collects the signals in one passage. The optical system uses an optical transceiver employing a light transmitter and a light receiver. This optical transceiver is formed in a unitary housing. The optical system includes first and second lenses which may be graded-index waveguide sections and a planar filter disposed therebetween, the planar filter typically being an interferential filter. The optical system is formed on a support which allows the light transmitter which is typically a laser to be disposed directly adjacent one of the lenses.

Abstract: A coupler (2,3) comprises, a central single mode optical fiber (5) and N number of glass fibers (4), having radii of equal dimensions, fused together along biconic tapered sections (13, 13) to couple optical power from the central fiber (5) completely and uniformly to only the fibers (4) that have optical cores (6).

Abstract: A robust optic fiber coupler which connects to an optic fiber cable via a quick disconnect optic fiber connector. The robust coupler contains a GRIN lens positioned in a bore through the coupler axially aligned with the optic fiber. The GRIN lens acts to expand and collimate input/output optic signals which are then passed through a protective window in the axial bore and emitted from the end plate face of the robust coupler. The optic signals are coupled between two optic fiber cables, each fitted with a subject robust coupler, when the coupler end plate faces are positioned adjacent to each other with each axial bore and associated GRIN lens and optic fiber commonly and axially aligned through a process such as a robotic arm and end effector connection.

Abstract: The present invention relates to a housing for an optical coupler. The housing includes a primary protective body having a receiving space therein, wherein the coupled portion of the coupler is positioned. A support material at least partially about the coupled portion of the coupler extends in the receiving space to the primary protective body. The support material is resilient and has an index of refraction less than that of the coupled portion of the coupler.

Abstract: The present invention is directed to an optical coupler, only formed by a plurality of all plastic fibers, and a method of producing the same. Two all plastic fibers each of which has a core are placed in contact with each other over a predetermined length. Ultrasonic vibration is applied to a contacting portion of the all plastic fibers so as to bond the cores with each other at the contacting portion. Thus, the optical coupler with a low-excess-loss can easily be produced.

Abstract: A fused coupler is formed from two twisted optic fibers (2, 3) of fluoride glass by heating them in the slot (18) of a temperature-controlled heater (15) in a shroud (14) containing an oxygen-free atmosphere. The glass of the fibers may be ZBLAN glass in which case the temperature is 323.degree. C..+-.10.degree. C. In an alternative embodiment the shroud is dispensed with and inert gas (nitrogen) is injected into a hole in the slot (18).

Abstract: An optical power summing apparatus that allows a multiplicity of optical signals to be combined with minimal signal transmission loss. A single photodiode simultaneously receives all of the input signals to perform a summation of signal powers. Alternative embodiments of the apparatus use either a tightly packed bundle of etched optical fibers or a converging arrangement of optical waveguides on a dielectric substrate to focus the optical signals onto the base region of a single photodiode.

Abstract: The method consists of first splicing (FIG. 2) one short length of a single-mode fiber (3, 4) into each of the optical fibers (1, 2) of fibers lying parallel to each other (FIG. 1), then fusing the two spliced-in single-mode fibers (3, 4) together (FIG. 3) and pulling them to form a coupler (6) (FIG. 4), and then embedding the coupler (6) in a protective housing (7) up to points beyond the splices (5).

Abstract: The invention provides a method for fabricating a polarization independent narrow channel wavelength division multiplexing fiber optic coupler, comprising the steps of: holding two optical fibers in an abutting longitudinal relation along a predetermined length of the fibers; injecting light energy into one of the fibers; fusing the optical fibers together along the predetermined length to form a fused length of a fiber optic coupler; elongating the fused length of the fusing optical fibers; measuring the light energy output from the ends of the first and second fibers; ceasing the fusing and elongating when the measured light energy output from the ends of the first and second fibers indicates that a predetermined number, N.sub.S, of one-half power transfer cycles have occurred in the coupler, where the N.sub.S th one-half power transfer cycle occurs within a K.pi. phase region of a polarization envelope associated with the coupler, where K is a positive integer.

Abstract: The optical waveguide coupler device is formed on two laterally adjacent optical fibers for splitting with wavelength-flattened ratios an incident light intensity into the two fibers. Adjacent sections of the two fibers are fused together and first and second concatenated tapered portions are formed. These two tapered portions are separated by a central optical waveguide portion including two parallel branches of slightly different lengths, each capable of propagating a light signal from either tapered portion to the other. The first and second tapered portions define optical waveguide couplers presenting coupling ratios varying with optical wavelength in accordance with different curves. The different lengths of the two parallel branches of the central portion cause a shift .phi. between the phases of the optical signals propagating through these two branches. The coupling ratios of the tapered portions and the phase shift .phi. are selected to wavelength-flatten the coupling ratios of the coupler device.

Abstract: A fiber optic attenuator having a predetermined, fixed attenuation value and low back reflection properties across a broad wavelength spectrum is disclosed. Attenuation is achieved by providing an optical fiber pathway having an attenuation region which causes a predetermined signal loss. The medium defining the pathway is of a substantially constant index of refraction through the device to minimize or eliminate interference caused by Fresnel reflections.

Abstract: Two single mode optical fibers are reduced in diameter over a predetermined length to form reduced-diameter portions whose center portions have different diameters. The two optical fibers are intersected at a small angle to each other substantially centrally of their reduced-diameter portions and then are fused together at the intersecting portions and the fused portions of the two optical fibers are heated and stretched to provide an optical coupler having a desired coupling ratio.

Abstract: A method of fabricating an optical branching and coupling device includes the steps of preparing at least a pair of coated optical fibers; partly stripping the coating of the optical fibers; and fixedly inserting the coating stripped portions of the optical fibers into a pair of comb-shaped grooves under a condition prior to a unification step which is free from tension and torsional stress in an optical axial direction to bring the coating stripped portions into contact with each other between the comb-shaped grooves. The method also includes the steps of melting the coating stripped portions thus contacting each other by heating to unify the coating stripped portions and extending the coating stripped portions in the optical axial direction while in the melted state.

Abstract: Two single mode optical fibers are stretched to form prestretched portions of different diameters, and then the optical fibers are fused together at their prestretched portions to form a coupling region which is stretched to obtain a wide-band optical fiber coupler of a desired splitting ratio.

Abstract: A fiber is mounted with a bare portion extending between two blocks. Four blocks securing a pair of fibers in this manner are mutually aligned by one or more external sleeves, and the fibers are fused and drawn to form a coupler of defined coupling ratio. One sleeve then slides over all four blocks and is bonded to constitute a rigid housing surrounding the fusion region. A preferred coupling block is a grooved D-rod, and different geometries are shown to provide effective PZ and PM fusion couplings, with fiber stress axes aligned with respect to a flat surface of the rod. Portions of the rod provide fiber support and alignment during fusion, and break away from the assembled coupler when complete.

Abstract: A coupling arrangement for optically coupling a fiber to a planar optical waveguide integrated on a substrate, such as employed in silicon micromechanical units. The substrate together with the waveguide and a cover member placed over the waveguide form component parts of a carrier member. The carrier member is fashioned such that the end of the waveguide lies in an end face of the carrier member. Two triangular openings between which the waveguide is arranged, are fashioned in the end face of the carrier member. The end face of the carrier member has a dimension similar to an outside diameter of the fiber and the end face of the fiber has its outer circumference welded to the end face of the carrier member.

Abstract: A semiconductor laser module comprises a semiconductor laser device, an optical fiber, and a lens for coupling light emitted from the semiconductor laser device to the optical fiber. There is provided a metal base having a flat portion and a pipe portion in a metal case. The semiconductor laser device is mounted on a chip carrier which is mounted on the flat portion of the metal base. The lens is fixed in the inside of the pipe portion of the metal base. The optical fiber is protected at one end by a ferrule which is fixed to the pipe portion of the metal base. A device such as a monitor photodiode and a thermistor may be mounted on the flat portion of the metal base. The flat portion of the metal base may be formed with a concave portion of an area smaller than an area of the bottom of the chip carrier.

Abstract: During the process of manufacturing polarization-selective fused-fiber couplers (1) having two or more input fibers and two or more output fibers and formed in the coupling region (fused region 6) from parallel, nonbirefringent, matched-cladding single-mode fibers, prior to the fusion of the fibers, linearly polarized light with a selected wavelength is fed into one of the input fibers (2) and detected at the ends of the two output fibers (3). The fibers are thereupon fused together with the coupler (1) being drawn until the coupling between the two fibers ceases to fluctuate. The source of heat is then turned off. With the method it is possible to manufacture fused-fiber couplers (1) whose lengths are only approximately 10 mm to 15 mm.