An article of manufacture including a fiber optic termination of a small core optical fiber for use with a surgical laser (characterized by a high M.sup.2 factor) or other high-power or high-energy pulse laser is configured for safe and efficient coupling of light at a large laser focal point and/or to enable the process of coupling of radiant intensities exceeding the silica fiber damage thresholds and/or those ionizing the air if fully focused therein. The termination includes a glass cylinder structured to include a core region and a glass cladding region the ratio of dimensions of which is substantially equal to the ratio of respectively-corresponding dimensions of the employed optical fiber. A method of coupling laser light characterized by an M.sup.2 factor of 25 or higher into an optical fiber with the use of same.

In various embodiments, the beam parameter product and/or beam shape of a laser beam is adjusted by coupling the laser beam into an optical fiber of a fiber bundle and directing the laser beam onto one or more in-coupling locations on the input end of the optical fiber. The beam emitted at the output end of the optical fiber may be utilized to process a workpiece.

Embodiments of the present disclosure include optical transmitters and transceivers with improved reliability. In some embodiments, the optical transmitters are used in network devices, such as in conjunction with a network switch. In one embodiment, lasers are operated at low power to improve reliability and power consumption. The output of the laser may be modulated by a non-direct modulator and received by integrated optical components, such as a modulator and/or multiplexer. The output of the optical components may be amplified by a semiconductor optical amplifier (SOA). Various advantageous configurations of lasers, optical components, and SOAs are disclosed. In some embodiments, SOAs are configured as part of a pluggable optical communication module, for example.

A laser delivery device may include a connector portion at a proximal end of the laser delivery device and an optical fiber connecting the connector portion to a distal end of the laser delivery device. The connector portion may include a capillary at least partially surrounding a proximal portion of the optical fiber, and the capillary may include dimples on at least a portion of a circumferential surface thereof.

In various embodiments, the beam parameter product and/or beam shape of a laser beam is adjusted by directing the laser beam across a path along the input end of a cellular-core optical fiber. The beam emitted at the output end of the cellular-core optical fiber may be utilized to process a workpiece.

In various embodiments, one or more optical elements are utilized to alter the numerical aperture of a radiation beam received from an optical fiber in order to accommodate the properties of a downstream collimator within a laser delivery head.

An optical coupler includes: input-type optical fibers; an output-type optical fiber; and radiant light processing units. The input-type optical fibers are bundled at leading end side to form a fiber bundle portion, and leading end portion of the fiber bundle portion is connected to the output-type optical fiber. In at least either the input-type optical fibers or the output-type optical fiber, a tapered portion is formed in which cross-sectional area is tapered to become narrower in light traveling direction indicating direction from the input-type optical fibers toward the output-type optical fiber. The number of the tapered portion is equal to or greater than two. Each radiant light processing unit is disposed to mutually overlap with one of the tapered portions or away from one of the tapered portions in the light traveling direction, and is disposed on outer periphery of the input-type optical fibers or the output-type optical fiber.

Methods include, for each of a plurality of pluggable optical transceivers that are fiber-coupled to respective inputs of a passive wavelength division multiplexer having a predetermined loss profile defining a path specific loss between each input and a common output, sending an optical output signal along an optical signal path while the other optical transceivers of the plurality are not sending optical output signals and measuring an optical power of the sent optical output signal at an input of a local optical amplifier downstream from an output of the wavelength division multiplexer, wherein the local optical amplifier is configured to transmit the optical output signals to a distant location, and, based on the measured optical powers, determining a loss distribution across the optical output signals at the input of the local optical amplifier by subtracting the predetermined path specific losses of the wavelength division multiplexer, comparing a variation in the loss distribution to a nominal variation to determine a defect in a transceiver fiber path associated with a higher loss component of the distribution where the variation exceeds the nominal variation, comparing an average or maximum loss in the loss distribution to a nominal average or maximum allowable loss to determine a defect in a common fiber path downstream from the multiplexer, and adjusting one or more of the optical powers of the optical output signals produced by the optical transceivers before transmission through the multiplexer, by an optical power offset that produces a predetermined flat optical power spectrum profile at the input of the local optical amplifier and that increases a transmission distance over which the optical output signals decodably propagate.

A method of processing by controlling one or more beam characteristics of an optical beam may include: launching the optical beam into a first length of fiber having a first refractive-index profile (RIP); coupling the optical beam from the first length of fiber into a second length of fiber having a second RIP and one or more confinement regions; modifying the one or more beam characteristics of the optical beam in the first length of fiber, in the second length of fiber, or in the first and second lengths of fiber; confining the modified one or more beam characteristics of the optical beam within the one or more confinement regions of the second length of fiber; and/or generating an output beam, having the modified one or more beam characteristics of the optical beam, from the second length of fiber. The first RIP may differ from the second RIP.

A fiber connector, comprising a housing comprising a region extending in a lengthwise direction an optical fiber disposed in the region, a first portion of the optical fiber comprising an inner core, a cladding layer surrounding the core, and a first outer polymer layer surrounding the cladding layer and a second portion of the optical fiber comprising the inner core, the cladding layer surrounding the core and a second outer polymer layer that is different from the first polymer layer.