摘要:
An optical fiber coupler capable of providing a low loss, high coupling coefficient interface between conventional optical fibers and optical waveguide devices is provided. The novel coupler, which may be polarization maintaining, if a polarization maintaining preform is used in its fabrication includes a core, a cladding, a first end for interfacing with an optical fiber and a second end for interfacing with an optical waveguide device. The sizes of the core and cladding are gradually reduced from the first end to the second end in accordance with a predetermined reduction profile. Various parameters, such as refractive indices and sizes of the core and cladding and the reduction profile are selected to produce a low numerical aperture at the first end and a high numerical aperture at the second end, while advantageously minimizing insertion loss and maximizing the coupling coefficient at each end. In another embodiment, the novel coupler includes a secondary cladding which is also reduced between the first and second ends to improve the strength of the coupler structure at the second end. In yet another embodiment, one or two novel couplers are formed along with a chiral fiber based optical waveguide device as a single continuous element. The optical fiber preform used to fabricate the novel optical fiber coupler can be etched prior to fabrication to facilitate application of the reduction profile.
摘要:
The inventive optical fiber coupler array is capable of providing a low-loss, high-coupling coefficient interface with high accuracy and easy alignment between a plurality of optical fibers (or other optical devices) with a first channel-to-channel spacing, and an optical device having a plurality of closely-spaced waveguide interfaces with a second channel-to-channel spacing, where each end of the optical fiber coupler array is configurable to have different channel-to-channel spacing, each matched to a corresponding one of the first and second channel-to-channel spacing. The novel optical coupler array includes a plurality of waveguides (at least one of which may optionally be polarization maintaining), that comprises at least one gradually reduced vanishing core fiber, at least in part embedded within a common housing structure. Alternatively, the novel coupler array may be configured for utilization with at least one of an optical fiber amplifier and an optical fiber laser. Advantageously, the refractive indices and sizes of both inner and outer core, and/or other characteristics of vanishing core waveguides in the novel optical coupler array are optimized to reduce the back reflection for light propagating from the plurality of the optical fibers at the coupler first end to the optical device at the coupler second end, and/or vice versa.
摘要:
The inventive optical component assembly advantageously enables a multi-waveguide optical component (such as the inventive optical fiber coupler array, a multi-core optical fiber, etc.), to be coupled to at least one waveguide of an optical device at a predefined coupling angle. The optical component assembly of the present invention comprises a multi-waveguide optical component with an output end, a prism having an input surface, an output surface, and an internal reflective surface with a predefined reflection angle, and a GRIN lens, positioned between the component output end and the prism input surface, along a longitudinal axis of the multi-waveguide optical component. In accordance with the present invention, the length of the GRIN lens, and its refractive index gradient profile are optimized to form an optical image of the output end of the multi-waveguide optical component, at the output surface of the prism, thus enabling the output surface of the prism to be coupled to at least one waveguide of an optical device, with the predefined reflection angle corresponding to the angle at which the multi-waveguide optical component may be coupled to the optical device.
摘要:
An optical fiber mode coupling device, capable of being readily connected to a conventional optical fiber with a high degree of ruggedness, is provided. The inventive mode coupling device only allows transmission of at least one supported fiber mode therethrough, and is preferably configured to maximize the coupling, of at least one desired fiber mode, to the at least one supported fiber mode. Advantageously, the inventive mode coupling device is capable of performing the functions of a mode filter for the signal entering its first end, or serving as a mode conditioner for the signal entering its opposite second end. Thus, in one practical application thereof, the novel mode coupling device functions as a mode filter by maximizing the coupling between at least one desired fiber mode of a multi-mode input signal entering the device's first end, and at least one supported mode of the device, to produce an output signal at the device's second end that comprises at least one predetermined fiber mode, corresponding to at least one desired fiber mode. In another practical application thereof, the novel mode coupling device functions as a mode conditioner by maximizing the coupling between an input signal, comprising at least one predetermined fiber mode, that enters the device's second end, and, and at least one supported mode of the device, to produce an output signal at the device's first end that comprises at least one desired fiber mode, corresponding to a conditioned at least one predetermined fiber mode.
摘要:
The inventive configurable chiral fiber sensor with a tip-positioned sensing element, is readily configurable for use in a variety of applications (such as applications involving pressure, temperature, and even axial twist sensing), and is particularly suitable for applications requiring highly precise and accurate sensor readings within corresponding predefined limited sensing ranges. Advantageously, the inventive configurable chiral fiber sensor with a tip-positioned sensing element, is operable to utilize a wide variety of light sources, photodetectors, and related devices for sensor interrogation.
摘要:
The inventive high density optical packaging header apparatus, in various embodiments thereof, provides configurable, modular, and highly versatile solutions for simultaneously connecting multiple optical fibers/waveguides to optical-fiber-based electronic systems, components, and devices, and is readily usable in a variety of applications involving highly flexible and modular connection of multiple optical fibers/waveguides assembled in a header block configuration to optical-fiber-based system/component backplanes, while providing advantageous active and passive alignment features.
摘要:
A single helix chiral fiber grating of a predetermined grating strength is provided that is operable to control light transmission in a predetermined wavelength range. The novel fiber grating comprises a first optical fiber with a first interface portion at a first end, a second interface portion at a second end, and a middle portion therebetween. The first optical fiber is configured with at least one fiber core, surrounded by a corresponding at least one cladding, with a first longitudinal section disposed within the first interface portion, a second longitudinal section disposed within the second interface portion, and also includes a longitudinal helical section, disposed therebetween within the middle portion, that comprises a longitudinal helix structure of a single predetermined handedness, having a predetermined pitch profile, and having a predetermined helix diameter profile selected and configured to produce the predetermined grating strength. The helical section of the novel fiber grating is preferably produced by placing the first optical fiber, proximal to and parallel with a second fiber (or equivalent elongated member), and longitudinally twisting them together to form a double helix structure. Advantageously, the diameter of the second fiber (or a diameter profile thereof) may be selected to achieve the predetermined helix diameter profile in the helical section of the first fiber. The second fiber may be left proximal to the first fiber after fabrication or removed.
摘要:
An optical fiber coupler array capable of providing multiple low loss, high coupling coefficient interfaces between a predetermined number of low numerical aperture optical fibers and an optical waveguide device with at least a corresponding number of waveguide interfaces. The novel coupler array includes a plurality of coupler inner cores and a plurality of corresponding coupler outer cores, within a medium surrounding each outer core, and also includes a first end for interfacing with optical fibers and a second end for interfacing with a plurality of waveguide interfaces of an optical waveguide device. The sizes of the inner and outer cores are gradually reduced from the first end to the second end in accordance with at least one predetermined reduction profile, such that the coupler array comprises a plurality of low numerical aperture waveguides at the first end, and a plurality of high numerical aperture waveguides at the second end.
摘要:
An optical fiber coupler array capable of providing multiple low loss, high coupling coefficient interfaces between a predetermined number of low numerical aperture optical fibers and an optical waveguide device with at least a corresponding number of waveguide interfaces. The novel coupler array includes a plurality of coupler inner cores and a plurality of corresponding coupler outer cores, within a medium surrounding each plural outer core, and also includes a first end for interfacing with plural optical fibers and a second end for interfacing with a plurality of waveguide interfaces of an optical waveguide device. The sizes of the inner and outer cores are gradually reduced from the first end to the second end in accordance with at least one predetermined reduction profile. Various parameters, such as refractive indices and sizes of the inner and outer cores and the medium (as well as the reduction profile) are selected to produce a plurality of low numerical aperture waveguides at the first end, and a plurality of high numerical aperture waveguides at the second end, while advantageously minimizing insertion loss and maximizing the coupling coefficient at each end. Advantageously, the novel coupler array may be fabricated as an array of individually drawn couplers from multiple parallel fused performs (arranged in a row, or in another geometric cross section). Alternately, the novel coupler array may be fabricated from a single perform (glass or polymer) embedded with a plurality of parallel inner and outer core sets.
摘要:
The system and method of the present invention advantageously enable controllable light extraction from optical fiber waveguides and offer highly configurable light signal guidance and control capabilities, as well as additional advantageous features associated with waveguides, by providing, in various exemplary embodiments thereof, a multitude of novel techniques by which the parameters relating to utilization of various light signals (such as direction of their emission, magnitude of the emission, physical surface area of the emission, etc.), can be readily controlled and configured as a matter of design choice. Additionally, the inventive system and method, in various exemplary embodiments thereof, also enable and facilitate selective configuration of, and/or control over, various characteristics of the light signals guided/controlled/extracted thereby, such as the signals' wavelength, polarization, intensity, amplitude, etc. To achieve the above-noted beneficial functions, the system and method of the present invention utilize a physical property of a standard, or a specialty, chiral optical fiber to scatter light signals entering the fiber in directions away from the fiber core (through the fiber cladding), to thereby advantageously enable selective and controllable extraction of light signals of a desired predetermined wavelength (or, optionally of a predetermined range of wavelengths) therefrom.