Abstract: A low-cost approach is provided for forming a low splice loss, low back reflection loss and mechanically robust angle-fusion splice between a standard silica fiber and a low-temperature non-silica glass fiber. This is accomplished by angle cleaving the silica fiber, square cleaving the non-silica fiber and then asymmetrically heating the fibers to form an angle fusion splice. A matched angle at the end of the non-silica fiber is generated in situ during the splicing process. The tip of the angle-cleaved silica fiber may be polished flat back to the edge of the core to reduce the range of motion of the non-silica fiber during splicing thereby further reducing splice loss and enhancing the mechanical strength of the joint.

Abstract: In a method for fusing splicing optical fibers having different diameters of fiber coating portions, the fiber coating portions of optical fibers to be spliced are clamped on V-groove boards and end faces of the optical fibers are aligned. Then, the end faces of the optical fibers are fused spliced by a discharged heating. An inclination angle &thgr;g of glass fibers of the fusion spliced optical fibers is measured from an observed image of a fusion splicing portion after fusion splicing the optical fibers to estimate a splice loss of the optical fibers.

Abstract: A low splice loss optical fiber transmission line is disclosed which has a first optical fiber portion and a second optical fiber portion, the first and second optical fiber portions having different mode field diameters. The optical fiber transmission line is advantageously loss-flattened. Additionally, a method of making an optical fiber transmission line is disclosed such that the loss due to the spliced connection is reduced during the fabrication of the optical transmission line.

Abstract: An automated fusion system includes a draw assembly for holding optical fibers and for applying a tension to the fibers. The fibers are held substantially parallel to each other in the draw assembly. The system also includes a removal station that etches or strips buffer material from the fibers after the fibers have been placed in the draw assembly, and a heater or torch assembly for heating the fibers as the draw assembly applies a tension to the fibers in a manner that causes the fibers to fuse together to form a coupler region. In addition, a packaging station is used to secure a substrate to the coupler region of the fibers to form the optical coupler.

Abstract: A system is disclosed for assembling optical components relative to one another, the system comprising: a plurality of carrier components, each one of the carrier components having a base portion, a top surface and a bottom surface of the base portion in opposition to one another, the base portion defining a given geometric shape, and at least one of the optical components disposed on the top surface of the base portion; an optical platform having an upper surface and a lower surface in opposition to one another, the upper surface of the optical platform having alignment patterns extending upwardly therefrom, and the alignment patterns defining a plurality of regions therebetween on the optical platform, wherein one of the regions is configured to secure the given geometric shape of the base portion of one of the carrier components thereto; and alignment means for aligning an optical transmission between the optical components mounted on separate ones of the carrier components.

Abstract: Good quality fusion splicing of optical fibers with very different melting points (even 800° C. and 1800° C.) can be achieved by heating the end (3) of the fiber of lower melting point to a substantial extent (preferably entirely) by conduction from the pre-heated end (4) of the fiber of higher melting point. Preheating is suitably by a laser with its beam (15) centered close to the interface between the two fibers (or slightly displaced in the direction of the fiber of higher melting point if the intensity of the beam is relatively evenly spread) using a screen (13) to shade the fiber of lower melting point from the beam.

Abstract: The present invention relates to an optical fiber device having a structure for effectively restraining the splice loss from increasing between two kinds of optical fibers having respective mode field diameters different from each other. The optical fiber device comprises first and second optical fibers fusion-spliced to each other, which are partly heat-treated such that both of their respective ratios of change in mode field diameter in the longitudinal direction become a predetermined value or less after fusion-splicing. When the ratios of change in mode field diameter in the vicinity of the fused point are appropriately controlled as such, the increase in splice loss at the fused point between the first and second optical fibers is effectively suppressed.

Abstract: A fusion splicer and fusion splicing method for optical fibers is disclosed including a TV camera 32 which obtains transmitted light images passing through side areas of respective optical fibers 10, 20, an image processing unit 33 which calculates mode field diameters of the respective optical fibers from brightness distributions of the images in terms of directions traverse to the optical fibers to calculate a diametric difference between the mode field diameters, a movable base 57 to move abutted portions between the optical fibers relative to an electric discharge beam position, a drive unit 35 which implements additional electric discharge heating after applying electric discharge fusion splicing heating to the abutted portions while moving the electric discharge beam position toward one of the optical fibers, of which mode field diameter is regarded to be small, and a control unit 34 which controls an electric discharge power supply 36.

Abstract: An optical fiber fixing system includes a clamp base and a clamp member. The clamp base has a V-groove on a top surface thereof. The depth of the V-groove is configured such that a ridgeline of an optical fiber projects beyond the top surface of the base when the optical fiber is mounted therein. The clamp member has a protrusion on a bottom surface thereof. The protrusion depresses, from the upside, the optical fiber mounted in the V-groove of the clamp base. Further, the protrusion is configured to extend substantially perpendicularly to the axial direction of the optical fiber.

Abstract: It is an object of the present invention to enable quick, easy, and inexpensive connections even in a narrow area using an inexpensive device and an inexpensive optical fiber connecting element, thereby achieving high operability and high durability reliability. An optical fiber connecting element includes an optical alignment sleeve having tapered insertion ports formed at opposite ends thereof and having an ejection port opened in an area in which the two optical fibers inserted through the insertion ports are butted against each other, a cyanoacrylate-type glue injected into the insertion ports and the injection port to fix the two optical fibers, and a heat-shrinkable tube wrapped around the optical alignment sleeve and two optical fiber coatings and having a hot-melt adhesive provided therein.

Abstract: A method and apparatus for aligning an optical waveguide with a radiation source are provided. The waveguide has a longitudinal axis that defines a main optical propagation path. The optical waveguide is illuminated by the radiation source such that the waveguide generates light via photoluminescence, at least a portion of the light generated via photoluminescence being emitted from the waveguide along a direction generally transverse to the longitudinal axis. An output signal is generated at least in part on the basis of light emitted from the waveguide along a direction generally transverse to the longitudinal axis. The alignment of the radiation source and the waveguide is varied at least partly in dependence of the output signal.

Abstract: The present invention relates to a method of splicing together two optical waveguides, such as an optical fibre and a planar waveguide, or two optical fibres. The method involves the steps of etching a terminal end of an optical fibre in the manner so as to create a tapered core projection. Another optical fibre or waveguide has a complimentary recess etched therein. The projection and recess are placed together and the waveguides moved together to facilitate alignment of the respective cores of the waveguides. A tube etching method is utilised to create the projection.

Abstract: There are provided a method of manufacturing a glass part for connecting optical fibers, which allows insertion of optical fibers into the internal hole of the glass part smoothly, and glass parts for connecting optical fibers manufactured using the method. Predetermined parts of a glass tube having an internal hole are heated while pressure is applied into the internal hole, to expand the predetermined parts, thus forming tapered portions. As a result, a continuous curved surface can be achieved at the boundary between each tapered portion of each obtained glass part and the internal hole thereof, and the surface can be made smooth where the tapers are formed.

Abstract: An optical fiber splicing device has guide grooves for aligning fiber ends. The fibers ends are held in the grooves by hold-down means including cylindrical pressing surfaces which are capable of rotating freely. Due to the free rotation, when lowering the hold-down means to hold the fiber ends, no longitudinal displacement of the fiber ends will occur and the fiber ends maintain their initial positions. The fiber ends are, after the holding operation having been completed, moved linearly, sliding in the guide grooves, an accurate linear movement being obtained from double parallelogram structures. Electrodes between which an electric arc is formed for heating the fiber ends at a splice position to fusion splice them to each other are given accurate, predetermined positions by means of adjustable positioning rings mounted to the electrodes.

Abstract: An optical fiber splicer includes a pair of retainers for retaining optical fibers to be spliced, a block formed with a groove of V-shaped cross-section, and abutment and pressure-contact mechanism for sliding terminal portions of the optical fibers in mutually opposite directions along the groove, producing substantially equal elastic forces in the terminal portions, bringing the terminal portions into abutment, and bringing the abutted terminal portions into pressure contact. An optical fiber splicing method includes a step of sliding terminal portions of optical fibers to be spliced along a groove of V-shaped cross-section in mutually opposite directions and producing substantially equal elastic forces in the terminal portions, and a step of bringing the terminal portions into abutment and then bringing the abutted terminal portions into pressure contact.

Abstract: In-situ and post-cure methods of joining optical fibers and optoelectronic components are provided. An in situ method of joining an optical fiber to an optoelectronic component includes positioning an optical fiber and optoelectronic component in adjacent relationship such that light signals can pass therebetween, applying a curable resin having adhesive properties to an interface of the optical fiber and the optoelectronic component, aligning the optical fiber and optoelectronic component relative to each other such that signal strength of light signals passing between the optical fiber and the optoelectronic component is substantially maximized, and irradiating the interface with non-ionizing radiation in RF/microwave energy to rapidly cure the resin.

Abstract: An optical fiber transmission line including first, second and third optical fibers connected together so that light travels through the transmission line from the first optical fiber, then through the second optical fiber and then through the third optical fiber. The first, second and third optical fibers have first, second and third characteristic values, respectively. The second characteristic value is larger than the first characteristic value and the third characteristic value. The characteristic value of a respective optical fiber being a nonlinear refractive index of the optical fiber divided by an effective cross section of the optical fiber. Pump light is supplied to the transmission line so that Raman amplification occurs in the transmission line as an optical signal travels through the transmission line.

Abstract: A low-cost approach provides a low loss and mechanically robust fusion splice between a standard silica fiber and a low-temperature multi-component glass fiber. An asymmetric heating configuration creates a temperature gradient between the silica and multi-component glass fibers that enhances diffusion, hence bond strength. The multi-component glass fiber may also be drawn with an outer cladding of a different multi-component glass. The outer cladding is selected so that it is thermally compatible with the multi-component glass used for the core and inner cladding and compatible with forming even stronger thermal diffusion bonds with the silica fiber.

Abstract: An optical fiber splicing method capable of fully reducing the splice loss at room temperature is provided. In the optical fiber splicing method in accordance with the present invention, respective end faces of optical fibers are fused together in a splicing step (S101). In a condition setting step (S102), a set value &agr;0 is set. Thereafter, a heating step (S103), a measuring step (S104), and a termination determining step (S105) are carried out repeatedly. In the heating step, a region including the fusion-spliced point is heated under a predetermined heating condition. In the measuring step, splice loss is measured. In the termination determining step, the splice loss &agr;n measured in the measuring step and the set value &agr;0 set in the condition setting step are compared with each other in terms of magnitude.

Abstract: Each of optical fibers has a core and stress applying members disposed around the core. End portions of the optical fibers are mounted on a fusion-splicing apparatus, and aligned through the image observation from two different lateral directions of the optical fibers. Then, a distance between positions of a bright portion end and a luminance peak closest to the bright portion end is obtained on each bright portion end of a luminance distribution of the optical fiber obtained from at least one picked-up image. The optical fibers are fusion-spliced by aligning the stress applying members so that the sum of the distances is adjusted to be minimum. Alternatively, a distance between positions of the luminance peaks respectively closest to the respective bright portion ends is obtained and the optical fibers are fusion-spliced by aligning the stress applying members so that the distance is adjusted to be maximum.

Abstract: A method of controlling an optical fiber splicing machine utilizes a power control mode to control the amount of power delivered to fuse the fibers. In the power control mode, the attenuation is measured while the fusing process is occurring. A rate of attenuation loss is predicted from the measured attenuation values by using an estimator. If the rate of attenuation loss indicates that a threshold insertion loss will be crossed before the next attenuation measurement, the splicing machine is stopped prior to the next attenuation measurement. If the desired attenuation is not achieved, an energy control mode is utilized which controls the amount of energy delivered to fuse the fibers. After delivering this energy, the method measures the attenuation. If not within desired values, the energy mode is repeated. At each iteration the splicing control function utilized by the energy control mode may be reprogrammed. A PID control formula may be used to determine the arc current for each iteration.

Abstract: Provided are an optical transmission line including a connected part of the optical fibers having different refractive index profiles, wherein at least one of the optical fibers has a hollow region, and a method for connecting such optical fibers, wherein connection loss in a connection of such optical fibers is reduced. In the case of connecting an optical fiber 1, which does not have a hollow region and which consists of a core region 3 and a cladding region 4, and an optical fiber 2, which consists of a hollow core region 5 and a cladding region 6 having a plurality of refractive index variation parts 7 which extend along optical fiber 2, matching oil M is first injected into the connecting end portion of the hollow core region 5 to be connected with the optical fiber 1. The matching oil M is a substance that has a matched refractive index greater than the refractive index of the material which forms the cladding region 6.

Abstract: Optical systems that include optical fiber splices are provided. Such an optical system includes first and second optical fibers, each of which has an end surface and a side surface adjacent to the end surface. An adhesive joins the end surface of the first optical fiber to the end surface of the second optical fiber. Additionally, at least a portion of the end surface of the first optical fiber exhibits a wettability for the adhesive that is higher than a wettability for the adhesive exhibited by at least a portion of the side surface of the first optical fiber. Methods and other systems also are provided.

Abstract: A method is described for producing a fiberoptic waveguide with a basic segment (11) and a phase shift segment (12), the basic segment (11) and phase shift segment (12) having fiber cores (K) of the same form and the fiber cores being aligned at a defined angle (&agr;) to one another. In the method, use is made of an optical fiber (1) having a fiber core (K) of the abovenamed form, which fiber is twisted at least approximately by the abovenamed defined angle (&agr;) and held fixed in this torsional position. Subsequently, a stress-relief zone (13) is heated inside the twisted fiber (1) until the torsion is released inside the stress-relief zone (13) and the basic segment (11) is produced on one side of the stress-relief zone (13) and the phase shift segment (12) is produced on the other side. In this case, the fixing of the torsional position is maintained until after solidification of the stress-relief zone (13).

Abstract: A fiber optic device for changing direction along a fiber optic path is provided. A first optical fiber having a first end portion, and a second optical fiber having a second end portion are joined at a fusion splice. A miniature bend is formed in the region of the fusion splice. The device is particularly useful for routing optical fibers in the field. A method of forming such a miniature bend in a fusion splice region between two optical fibers is also provided.

Abstract: A fiber splicing apparatus of the present invention includes a support (120a, 120b) for supporting the two optical fibers (112a,112b) such that the ends (114a, 114b) thereof are aligned and in physical contact, and a laser (130) emitting a laser beam (142) onto the ends of the optical fibers to heat and thereby fuse together the ends (114a, 114b ) of the fibers (112a, 112b). According to another embodiment, an apparatus is provided for heating a region (115) of one or more optical fibers(112a, 112b). This apparatus includes a laser (130) emitting a laser beam (132) and an optical modulator (134) positioned to receive and selectively modulate the intensity of the laser beam (132) to project a modulated laser beam (138) along a first optical path that terminates at the end (114a, 114b ) of the optical fiber(s) (112a, 112b)to be heated.

Abstract: A method of cross-connecting or reorganizing individual optical fibers of a plurality of fiber optic ribbons include the steps of providing a substrate having an adhesive thereon with a mixing zone within the boundaries thereof. A plurality of individual optical fibers are routed onto the substrate to form a plurality of fiber optic input ribbons, reorganizing the fibers in the mixing zone, and forming a plurality of fiber optic output ribbons. At least some of the output ribbons have fibers from more than one of the input ribbons. The input and output ribbons are coated on the substrate outside the mixing zone to hold the routed fibers in ribbon form, leaving at least portions of the fibers in the mixing zone uncoated. The coated ribbons are stripped from the substrate with the uncoated fibers from the mixing zone being loose. A holding device is placed about at least the uncoated loose fibers between the input and output ribbons.

Abstract: An optical transmission line with reduced splice loss, and methods for fabricating an optical transmission line with reduced splice loss, are described. In one described method, a length of dispersion-compensating fiber, or other suitable first transmission fiber, is spliced to a first end of a length of a bridge fiber. The splice is heated to a maximum temperature to cause a measurable reduction in splice loss. The temperature of the splice is then ramped down to room temperature, such that the reduction in splice loss is maintained. A second end of the bridge fiber is then spliced to a length of a second transmission fiber. Further described is a technique for determining the maximum temperature for heating the splice between the first transmission fiber and the bridge fiber.

Abstract: A bridge fiber and a method of connecting two other dissimilar optical waveguide fibers is presented. The bridge fiber may be utilized to connect positive dispersion fibers or step index single mode fibers to compensative fibers, such as dispersion compensation fibers or dispersion-slope compensation fibers.

Abstract: The present invention includes a composite optical waveguide fiber. The composite optical waveguide fiber includes a first optical waveguide fiber. The first optical waveguide fiber has a first diameter and a first outermost layer having a first coefficient of thermal expansion. The composite optical waveguide fiber further includes a second optical waveguide fiber coupled to the first optical waveguide fiber. The second optical waveguide fiber has a second diameter and a second outermost layer, the second outermost layer having a second coefficient of thermal expansion. Wherein the first coefficient of thermal expansion is greater than the second coefficient of thermal expansion. Wherein the first diameter is greater than the second diameter.

Abstract: A low-cost approach provides a low loss and mechanically robust fusion splice between a standard silica fiber and a low-temperature multi-component glass fiber. An asymmetric heating configuration creates a temperature gradient between the silica and multi-component glass fibers that enhances diffusion, hence bond strength. The multi-component glass fiber may also be drawn with an outer cladding of a different multi-component glass. The outer cladding is selected so that it is thermally compatible with the multi-component glass used for the core and inner cladding and compatible with forming even stronger thermal diffusion bonds with the silica fiber.

Abstract: A method for splicing optical fibers is disclosed. The fibers are held by ferrules with a softening temperature at least 30° C. below that of the lower of the glass transition temperatures of the fibers. The ends of the fibers are actively aligned and brought into contact, then energy is applied to fuse the ferrules together, maintaining the alignment of the ends of the fibers. The ferrules may be a low-melting inorganic glass, such as a lead bismuth borosilicate glass. The method and ferrules of the present invention are especially useful in splicing fibers of dissimilar thermomechanical properties.

Abstract: Improved apparatus and method allow rapid and precise alignment of a fiber optic array on a substrate, in which the offset between the end faces of the array and the edge of the substrate must be precisely known. The arrangement is adaptable for the construction of microlens assemblies and other optical elements that must be precisely placed proximate the end faces of the optical fibers.

Abstract: The connecting method of different kind optical fibers of the present invention is a connecting method able to improve the strength of connecting portions of the different kind optical fibers of different mode field diameters. In this connecting method, connecting ends of the different kind optical fibers removing their coating therefrom are mutually butted and fusion-spliced by gripping the coating in a step (S4). Next, the mode field diameters of different kind optical fiber connecting portions are conformed to each other by the heat treatment of a step (S5). This heat treatment is taken within a low dust space having a clean degree of 1000 or less in class. Thus, the heat treatment is taken under an environment in which foreign matters floated around the connecting portions of the different kind optical fibers are very small. Therefore, it is possible to restrain a crack from being caused by burning the foreign matters into the connecting portions.

Abstract: A method for splicing optical fibers is disclosed. The fibers are held by ferrules with a softening temperature at least 30° C. below that of the lower of the glass transition temperatures of the fibers. The ends of the fibers are actively aligned and brought into contact, then energy is applied to fuse the ferrules together, maintaining the alignment of the ends of the fibers. The ferrules may be a low-melting inorganic glass, such as a lead bismuth borosilicate glass. The method and ferrules of the present invention are especially useful in splicing fibers of dissimilar thermomechanical properties.

Abstract: A method of coupling optical waveguides comprising the steps of: (i) providing at least one pair of waveguides located such that (a) light radiation propagating through one of the waveguides will be at least partially coupled to a corresponding waveguide and, (b) these waveguides are separated by a gap of about 2 &mgr;m to about 500 &mgr;m long; the waveguides having positive dn/dT; (ii) filling the gap with a photo-polymerizable composition, the composition having dn/dT of −2×10−4/C to −4×10−4/C; (iii) providing simultaneous photo-radiation through said waveguides, wherein the photo-radiation photo-polymerizes the composition, thereby (a) creating a first region bridging between the waveguides, the first region having a first index of refraction, and (b) a second region encapsulating the first region, the second region having a second index of refraction, such that said first index of refraction of the first region is at least 0.

Abstract: The present invention relates to a method for mid-span branching of optical fiber cable which makes the mid-span branching possible without excess length of the optical fiber cable by forming main branching part and sub branching part for branched cores to be taken out from an existing main cable. It is an object of the present invention to provide a method for mid-span branching that provides marginal length of the existing main cable from which the branch cable branches off without the excess length of cables.

Abstract: An object is to provide an optical fiber fusion splicing method in which splice loss can be reduced, and also to provide an arc-heating unit used for heating the fusion spliced part of an optical fiber. The method comprises a process of fusion-splicing together the end faces of two optical fibers and a process of continuously heating the fusion spliced part by arc while moving one pair of electrodes provided opposite to each other across the fusion spliced part. The arc heating process is performed with the operation for decreasing arc temperature.

Abstract: An optical fiber splice protector protects a splice between a first optical fiber and a second optical fiber. The first optical fiber includes a first fiber coating and the second optical fiber includes a second fiber coating where the second fiber coating has a larger diameter than the first fiber coating. The splice protector includes a sleeve that is applied around the first fiber coating. The sleeve has a similar diameter to the diameter of the second fiber coating. A splint is applied around the splice of the first optical fiber and the second optical fiber and extends from the sleeve to the second fiber coating. Additionally, a method for applying a fiber optic splice protector is provided. The method includes the steps of positioning the splint around the splice, proof testing the splice, and heat curing the splint around the splice after proof testing of the splice.

Abstract: A method of controlling an optical fiber splicing machine utilizes a power control mode to control the amount of power delivered to fuse the fibers. In the power control mode, the attenuation is measured while the fusing process is occurring. The power control mode shuts down the splicer when the measured insertion loss is less than or equal to the target insertion loss value plus a margin value. The margin value accounts for the transient attenuation difference value indicative of the changing attenuation as the splice cools. If the desired attenuation is not achieved, an energy control mode is utilized which controls the amount of energy delivered to fuse the fibers. After delivering this energy, the method measures the attenuation. If not within desired values, the energy mode is repeated. At each iteration the splicing control function utilized by the energy control mode may be reprogrammed. With these techniques, optical fibers may be spliced having a controlled attenuation to within +/−0.

Abstract: Good quality fusion splicing of optical fibers with very different melting points (even 800° C. and 1800° C.) can be achieved by heating the end (3) of the fiber of lower melting point to a substantial extent (preferably entirely) by conduction from the pre-heated end (4) of the fiber of higher melting point.

Abstract: The invention is directed to a dispersion-compensating optical fiber which can compensate for the chromatic dispersion and dispersion slope of a non-zero dispersion-shifted optical fiber by a short length. The dispersion-shifted optical fiber constitutes an optical transmission line together with a dispersion-compensating optical fiber fusion-spliced thereto. The dispersion-compensating optical fiber has, at a wavelength of 1550 nm, a chromatic dispersion DDCF of −40 ps/nm/km or less and a ratio (DDCF/SDCF) of dispersion slope SDCF to the chromatic dispersion DDCF of 0.005/nm or more.

Abstract: A method of controlling an optical fiber splicing machine utilizes an optimized power control mode to control the amount of power delivered to fuse the fibers. The attenuation is measured while the fusing process is occurring and a final jump value is calculated. The final jump value is indicative of the transient attenuation difference that occurs as the splice cools. The optimized power control mode shuts down the splicer when the measured insertion loss is less than or equal to the difference between the estimated final jump value and the desired attenuation. The final jump value may also be recalculated as further data are gathered during the splicing process. If the desired attenuation is not achieved, an optimized energy control mode is utilized which determines optimal energy settings and controls the amount of energy delivered to fuse the fibers. After delivering this energy, the method measures the attenuation. If not within desired values, the optimized energy mode is repeated.

Abstract: In an optical connector, a sleeve is located between an optical fiber 6 and a light receiving/transmitting module 4 and makes an optical connection therebetween. The sleeve has a light guiding passage which is tapered from the optical fiber toward the light receiving/transmitting module, thereby forming a conical shape with its sloped side wall. The end face having a reduced diameter of the light-guiding passage 26 thus formed is arranged oppositely to the light receiving/transmitting module.

Abstract: The present invention relates to a positioning system for automatically positioning and attaching at least one optical fiber inserted into said positioning system along a predetermined optical axis. This positioning system comprises a base member with a flat upper surface and a V-shaped reception channel which is parallel to the upper surface and is formed therein for receiving at least one optical fiber. This system also includes a spring-effect retaining member which is mounted on the upper surface of the base member for maintaining the at least one optical fiber inserted into the reception channel. This invention provides for a simple structure, as well as, for a precise and mechanically resistant coupling since the retaining member comprises a membrane which is parallel to the upper surface of the base member, which is mounted above the reception channel and which can be resiliently diverted in a direction perpendicular to the upper surface of said base member.

Abstract: Splice between a first optical fiber, having a first propagation constant, and a second optical fiber, having a second propagation constant which is different from the first. The said splice comprises a coupling region between an end portion of the said first optical fiber and an end portion of the said second fiber, such that a coupling of at least 90% of the optical power in a waveband of at least 100 nm is obtained between the said first fiber and the said second fiber.

Abstract: A method and apparatus for assembling optical components and a substrate. A glass coating is located at the inner base between the optical component and the substrate. The assembly of the component, substrate and glass coating can be used in the field of imaging and in particular for endoscopy.

Abstract: In a process of splicing optical fibers, a temperature distribution during the splicing of the waveguides at a constant discharge current will depend on ambient parameters, which include temperature, air pressure and air humidity, and these parameters also influence the quality of the splice being produced. The discharge current is regulated by measuring the actual intensity distribution of the thermionic emissions of the waveguide during the splicing operation and by comparing this intensity distribution with a stored reference intensity distribution. The device includes a sensor which is used for measuring the intensity distribution and for adjusting the ends of the waveguides relative to each other.

Abstract: An optical fiber splice apparatus has a covering that surrounds the splice between two optical fibers, and conducts residual pump energy in the fiber claddings away from the splice. This prevents the residual light from reaching components, such as plastic buffers, that are susceptible to failure from excess light absorption. The apparatus may use an optical epoxy covering that surrounds adjoining portions of both fibers, and that has a refractive index higher than that of the outermost fiber claddings. The covering may be surrounded by a glass capillary that is transparent to the residual light, and that conducts light from the covering further away from the splice. The capillary may be mounted in a metal housing by an adhesive epoxy that is transparent to the residual pump light, and can conduct light to an inner surface of the housing, which may be light absorbent to the wavelength range of the residual pump light.

Abstract: An optical signal limiter is provided for limiting transmission of a continuous wave optical signal that exceeds a preselected threshold power level. The limiter includes a body having input and output ends that is formed at least in part from a material having a negative thermal index coefficient of between about −0.5×10−4 °C.−1 and −4.0×10−4 °C.−1 and an absorption coefficient of between 1.0 to 5.0 dB/cm at wavelengths between 980-1650 nm. The limiter also includes collimating fibers mounted on the input and output ends to minimize low power signal losses across the limiter body. It may be installed at a junction between two optical fibers and is preferably formed from a curable adhesive having the aforementioned negative thermal index coefficient to obviate the need for separate bonding materials and joining steps during the installation of the limiter.