Patent application number | Description | Published |
20080219624 | FIBER OPTIC CONNECTOR WITH DOUBLE-CLAD STUB FIBER - A fiber optic connector having a double-clad specialty optical stub fiber with a deep index core-to-inner-cladding profile and a raised index outer-cladding profile. The double-clad optical stub fiber abuts against a single-clad field optical fiber of the single-mode type to form an interface across which the primary mode traverses without significantly interfering with higher-order modes. The ratio of the radius of the inner cladding to the radius of the core of the stub fiber is less than 6.5:1. The index profile of the refractive index of the inner cladding is deep relative to the refractive index of the core to confine the primary mode within the core. The raised refractive index of the outer-cladding pulls the higher-order modes deeper into that region, reducing interference with the primary mode. The respective core diameters of the field and stub fibers are matched to avoid mode-field diameter mismatch. | 09-11-2008 |
20090074361 | Fiber optic connector with double-clad stub fiber - A fiber optic connector having a double-clad specialty optical stub fiber with a deep index core-to-inner-cladding profile and a raised index outer-cladding profile. The double-clad optical stub fiber abuts against a single-clad field optical fiber of the single-mode type to form an interface across which the primary mode traverses without significantly interfering with higher-order modes. The ratio of the radius of the inner cladding to the radius of the core of the stub fiber is less than 6.5:1. The index profile of the refractive index of the inner cladding is deep relative to the refractive index of the core to confine the primary mode within the core. The raised refractive index of the outer-cladding pulls the higher-order modes deeper into that region, reducing interference with the primary mode. The respective core diameters of the field and stub fibers are matched to avoid mode-field diameter mismatch. | 03-19-2009 |
20100154478 | MULTIMODE FIBER HAVING IMPROVED INDEX PROFILE - A graded index multimode fiber and method of producing the graded index multimode fiber utilize a technique of reducing an index profile of the core of the multimode fiber below a standard parabolic index profile. This can be done by changing dopant concentrations in the fiber core over the radius of the fiber core. The result is a multimode fiber having differential mode delay characteristics that are intentionally not minimized. The index profile can be reduced below the standard parabolic index profile over the entire radius of the core, or only for radii above a specified radius. | 06-24-2010 |
20100315620 | Method and Metric for Selecting and Designing Multimode Fiber for Improved Performance - A new metric applicable to the characterization and design of multimode fiber (MMF) is described. The metric is derived from a Differential Mode Delay (DMD) measurement and when used in combination with industry-standard metrics such as Effective Modal Bandwidth (EMB) and DMD, yields a more accurate prediction of MMF channel link performance as measured by Bit Error Rate (BER) testing. The metric can also be used in the design of MMF for improved bandwidth performance. When implemented as a test algorithm in production, it can be used to select, sort, or verify fiber performance. This process can yield a multimode fiber design with a greater performance margin for a given length, and/or a greater length for a given performance margin. | 12-16-2010 |
20110037183 | Self-Compensating Multi-Mode Fiber - An improved multimode fiber optic cable is designed to compensate for the wavelength distribution and emission pattern of laser sources used in high-speed communication systems. The improved multimode fiber optic cable compensates for the wavelength dependent VCSEL polar emission pattern to reduce modal dispersion. Techniques for reducing the modal dispersion within the improved multimode fiber optic cable allow for improved Bit Error Rate (BER) system performance and/or to achieve greater reach in high bandwidth optical channel links are disclosed. Considerable efforts have been undertaken in the design and production of an improved multimode fiber optic cable to minimize modal dispersion, ignoring the effects of wavelength dependent polar emission patterns in lasers. Material dispersion effects have a significant impact on modal dispersion and by modifying a standard parabolic refractive index profile to compensate for material dispersion effects, overall modal dispersion can be reduced. | 02-17-2011 |
20110044594 | Modified Refractive Index Profile For Low-Dispersion Multi-Mode Fiber - An improved multimode fiber optic cable is provided. The improved multimode fiber optic cable includes, but is not limited to, a refractive index profile which is designed to compensate for a radially dependent wavelength distribution of laser launch modes coupled into the multimode fiber optic cable in order to minimize modal dispersion within the multimode fiber optic cable. | 02-24-2011 |
20110054862 | Multimode Fiber Having Improved Reach - A means of improving the performance of laser optimized multimode fiber optic cable (MMF) to achieve improved optical margin and channel reach for use in high-speed data communication networks is described. The disclosed method can be used to improve the performance of both OM3 and OM4 grades of MMF. | 03-03-2011 |
20120099099 | Method for Designing and Selecting Optical Fiber for use with a Transmitter Optical Subassembly - A method for compensating for both material or chromatic dispersion and modal dispersion effects in a multimode fiber transmission system is provided. The method includes, but is not limited to measuring a fiber-coupled spatial spectral distribution of the multimode fiber laser transmitter connected with a reference multimode fiber optical cable and determining the amount of chromatic dispersion and modal dispersion present in the reference multimode fiber optic cable. The method also includes, but is not limited to, designing an improved multimode fiber optic cable which compensates for at least a portion of the chromatic dispersion and modal dispersion present in the reference multimode fiber optic cable resulting from the transmitter's fiber-coupled spatial spectral distribution. | 04-26-2012 |
20130070237 | Method and Metric for Selecting and Designing Multimode Fiber for Improved Performance - A new metric applicable to the characterization and design of multimode fiber (MMF) is described. The metric is derived from a Differential Mode Delay (DMD) measurement and when used in combination with industry-standard metrics such as Effective Modal Bandwidth (EMB) and DMD, yields a more accurate prediction of MMF channel link performance as measured by Bit Error Rate (BER) testing. The metric can also be used in the design of MMF for improved bandwidth performance. When implemented as a test algorithm in production, it can be used to select, sort, or verify fiber performance. This process can yield a multimode fiber design with a greater performance margin for a given length, and/or a greater length for a given performance margin. | 03-21-2013 |
20130289956 | Methods for Designing Improved Multimode Fiber Optic Cables - Methods for designing improved multimode fiber optic cables are provided. In an embodiment, the method includes measuring a DMD waveform profile of a reference multimode fiber optic cable, where the reference multimode fiber optic cable has a reference refractive index profile. The method of this embodiment further includes designing an improved refractive index profile for the improved multimode fiber optic cable, where the improved refractive index profile comprises the reference refractive index profile modified by a quantity Δn(r), where r is a radius from the center of the core, where the quantity Δn(r) is negative over at least some radial window, and where the quantity Δn(r) follows a function such that the improved multimode fiber optic cable having the improved refractive index profile produces a DMD waveform profile having a shift to the left in radial pulse waveforms for increasing radii. | 10-31-2013 |
20140204367 | Method for Designing and Selecting Fiber for Use with a Transmitter Optical Subassembly - A method for compensating for both material or chromatic dispersion and modal dispersion effects in a multimode fiber transmission system is provided. The method includes, but is not limited to measuring a fiber-coupled spatial spectral distribution of the multimode fiber laser transmitter connected with a reference multimode fiber optical cable and determining the amount of chromatic dispersion and modal dispersion present in the reference multimode fiber optic cable. The method also includes, but is not limited to, designing an improved multimode fiber optic cable which compensates for at least a portion of the chromatic dispersion and modal dispersion present in the reference multimode fiber optic cable resulting from the transmitter's fiber-coupled spatial spectral distribution. | 07-24-2014 |
20140241685 | MULTIMODE OPTICAL FIBERS AND METHODS OF MANUFACTURE THEREOF - The present invention generally relates to the field of fiber optics, and more specifically to optical fibers, methods of manufacturing optical fibers, and methods of classifying optical fibers. In an embodiment, the present invention is a multimode optical fiber which comprises a core and clad material system where the refractive indices of the core and cladding are selected to minimize chromatic dispersion in the 850 nm wavelength window and the refractive index profile is optimized for minimum modal-chromatic dispersion in channels utilizing VCSEL transceivers. Multimode optical fibers according to this embodiment may have increased channel bandwidth. | 08-28-2014 |
20150071586 | Multi-Channel, Multi-Port Optical Tap Coupler - A multi-channel, multi-port optical tap coupler with an alignment base element, a pair of sub-assemblies located at opposite ends of the alignment base element, focusing elements located next to each sub-assembly, and an optical filter adjacent to, and in-between the focusing elements is described. The first sub-assembly has an array of waveguides with each waveguide having a radial offset and an azimuthal position with respect to a center axis of the array. The first array includes transmission waveguides and receiving waveguides and each receiving waveguide has a corresponding transmission wave guide that is separated by an azimuthal angle of 180 degrees. The second sub-assembly has a second array of waveguides including a wave guide having the same radial offset and the same azimuthal position for each of the transmission wave guides of the first array. | 03-12-2015 |
20150071587 | Multi-Channel, Multi-Port Optical Tap Coupler - A multi-channel, multi-port bi-directional optical tap coupler with an alignment base element, a pair of sub-assemblies located at opposite ends of the alignment base element, focusing elements located next to each sub-assembly, and an optical filter adjacent to, and in-between the focusing elements is described. The first sub-assembly has an array of waveguides with each waveguide having a radial offset and an azimuthal position with respect to a center axis of the array. The first array includes transmission waveguides and receiving waveguides and each receiving waveguide has a corresponding transmission wave guide that is separated by an azimuthal angle of 180 degrees. The second sub-assembly has a second array of waveguides including a wave guide having the same radial offset and the same azimuthal position for each of the transmission wave and receiving guides of the first array. | 03-12-2015 |