Abstract: A fiber optic assembly includes a multi-port fiber optic device (100) with a buffer (200) circumferentially mounted thereon. A metallic foil (300) with the sealant (400)coated thereon, wraps around the buffered multi-port fiber optic device, and is crimped at two opposite longitudinal ends thereof. Both the buffer (200) and the sealant (400) are cured for reinforcement of the whole package assembly.

Abstract: The present invention, generally speaking, provides compact design of optical couplers for combining two differently polarized light beams onto a collimator or splitting a composed light beam into two differently polarized light beams. According to another embodiment, the size of the polarization beam combiner is minimized by using a pair of specially designed fiber collimators that use an asymmetrical sleeve. As a result, a coupler, according to the present invention, uses less components, is of small in size and provides an easy-aligning structure. Further the coupler offers lower optical insertion loss with minimized physical size.

Abstract: An optical fiber structure for demultiplexing/multiplexing includes a coupler which splits an incoming signal with multiple channels into two substantially identical signals that are respectively processed to separate the closely located successive channel groups for further demultiplexing or multiplexing. The spectrum characteristics to process the two identical signals are so chosen that the channel distortion and/or transmission loss are minimized. In particular, multiple stages of splitter filters are used to shorten the transmission path a channel signal has to pass through. As a result, signal distortion and/or transmission loss are minimized and the channel groups are interleaved by a single channel group.

Abstract: A retro-reflective multi-port fiber optic device includes the triple-fiber ferrule with a GRIN rod lens to couple the light. The triple-fiber ferrule with three fibers thereof is attached to the angled facet of the GRIN rod lens and the WDM filter is attached to the opposite side of the lens. A reflective mirror is aligned with and attached next to the other side of the WDM filter opposite to the lens. The triple-fiber ferrule, which is specifically selected from adense series of triple-fiber ferrules respectively defining three-fiber assemblies with different fiber spacings, is used to couple light in and out of the device, and tune the filter center wavelength to the desired ITU grid.

Abstract: A V-groove dual fiber DWDM collimator (1) including an optical lens (10) and a V-groove dual fiber ferrule means (12) fixed with each other. The ferrule means (12) includes a V-groove chip (14) and a cover chip (20) commonly enclosed by a protective guiding sleeve (22) wherein two pigtail fibers (24, 26) are respectively received within the corresponding grooves (16) of the V-groove chip (14). The V-groove ferrule means (12) is itself fixed by adhering its own internal components (14, 20, 22) and the embedded fibers (24, 26), and also fixed to the lens (10).

Abstract: An unpolarized monochromatic light source with wavelength tunable capability wherein a monochromatic laser source (10) is connected to an incoherent cascaded fiber-ring depolarizer (14) through a single mode fiber (16) under the condition that Ld>>LC wherein Ld is the length of fiber-ring delay line (18) and LC is the coherence length of the light source (10). The combination of the monochromatic laser source (10) and the incoherent cascaded fiber ring depolarizer (14) can be further connected to an external modulator (30) for amplitude modulation, frequency modulation, or phase modulation of the light signal.

Abstract: A multi-port fiber optic device (100) includes a pair of opposite collimators (50, 51), of which each includes a V-groove dual fiber ferrule (20, 21) with a GRIN rod lens (2, 1). At least one band-pass DWDM thin film filter (4) is securely sandwiched between the two opposite GRIN rod lens (2, 1) of the pair of collimators (20, 21). The V-groove dual fiber ferrule (20, 21) is used to couple light in and out thereof and tune the thin film filter center wavelength to the ITU grid. The light coupled in from the input fiber (13) of the V-groove dual fiber ferrule (20) will be collimated and transmitted to the DWDM thin film filter (4). The part of the in-pass-band light will pass through the filter (4) as performing a demultiplexed channel and is successively coupled into the other collimator (21) aside.

Abstract: Improved designs of fiber collimators that include an asymmetric sleeve are disclosed. According to one embodiment of the present invention, the asymmetric sleeve is so shaped that, when arranged next to each other, two collimators with the asymmetric sleeve achieves a lateral distance shorter than the outer diameter of the collimators, which makes it possible to design smaller optical components without effecting the performance and characteristics thereof.

Abstract: An optical depolarizer and method of depolarizing light is described. An input light beam is split into two beams. One split beam is recirculated through a birefringent medium and looped back to be recombined with the input light. This allows a weighted averaging of the different polarization states that result from birefringence in the recirculation path of the recirculated beam. The depolarizer is formed from single mode fiber optic cables and fused single mode fiber couplers. Each fiber coupler has an input pair of fibers and an output pair of fibers. One of the output fibers is coupled to one of the input fibers to form a recirculation loop. Additionally, polarization controllers provided in the input fiber and recirculation loop allow the degree of polarization of the output beam to be varied across a wide spectrum of values.

Abstract: A retro-reflective multi-port fiber optic device (100) includes the triple-fiber ferrule (10) with a GRIN rod lens (12) to couple the light. The triple-fiber ferrule (10) with three fibers (18, 20, 22) thereof is attached to the angled facet of the GRIN rod lens (12) and the WDM filter (14) is attached to the opposite side of the lens (12). A reflective mirror (16) is attached next to the other side of the WDM filter (14) opposite to the lens (12) after alignment. The triple-fiber ferrule (10) is used to couple light in and out of the device, and tune the thin film filter center wavelength to the desired ITU grid.

Abstract: A multi-port fiber optic device (10) includes a dual fiber first collimator (12) which comprises a ferrule (18) with the input fiber (30) and the output fiber (32) therein, a gradient index rod lens (20) adhesively attached to the ferrule (18), and a filter (22) adhesively attached to the lens (20) opposite to the ferrule (18). A second collimator (14) is generally positioned in front of the first collimator (12), includes the similar components thereof while being symmetrical to the first collimator (12) along the middle portion of the whole assembly, except that one of the dual fiber of the second collimator (14) functions idle, thus the pigtail of such a fiber being removed.

Abstract: A circulator (10) includes a first collimating device (12) and a second collimating device (16) with three external optic fibers (14), (18) & (20) thereon wherein the first fiber (18) and the third fiber (20) are coupled to the second collimating device (16) while the second fiber (14) is coupled to the first collimating device (12). A non-reciprocal section (22) is positioned between the first collimating device (12) and the second collimating device (16). The non-reciprocal section (22) includes a first optic isolator section (24) and a second optic isolator section (26) commonly sandwiching a first light deflecting device (28) therebetween, and a second light deflecting device (30) being positioned between the second optic isolator section (26) and the second collimating device (16).

Abstract: A dual fiber collimator (16) is provided in front of the neutral density (ND) filter (22) with a first fiber (18) and a second fiber (20) extending therefrom wherein the ND filter (22) is of a wedge configuration for eliminating oscillation thereof. A compensation lens (28) is positioned between the ND filter (22) and the collimator (16) for lowering the PDL of the attenuator (10).

Abstract: A protection cap for use with a fiber coupler having at least a first housing comprises a casing defining a passage therethrough for receiving at least a portion of the housing, and a covering lid pivotally assembled to the casing for enclosing an end of the passage.

Abstract: A V-groove dual fiber collimator (1) including an optical lens (10) and a V-groove dual fiber ferrule means (12) fixed with each other. The ferrule means (12) includes a V-groove chip (14) and a cover chip (20) commonly enclosed by a protective guiding sleeve (22) wherein two pigtail fibers (24, 26) are respectively received within the corresponding grooves (16) of the V-groove chip (14). The V-groove ferrule means (12) is itself fixed by adhering its own internal components (14, 20, 22) and the embedded fibers (24, 26), and also fixed to the lens (10).

Abstract: An optical depolarizer and method of depolarizing light is described. An input light beam is split into two beams. One split beam is recirculated through a birefringent medium and looped back to be recombined with the input light. This allows a weighted averaging of the different polarization states that result from birefringence in the recirculation path of the recirculated beam. The depolarizer is formed from single mode fiber optic cables and fused single mode fiber couplers. Each fiber coupler has an input pair of fibers and an output pair of fibers. One of the output fibers is coupled to one of the input fibers to form a recirculation loop. Additionally, polarization controllers provided in the input fiber and recirculation loop allow the degree of polarization of the output beam to be varied across a wide spectrum of values.

Abstract: An apparatus for measuring the IL (insertion loss) and the PDL (polarization dependent loss) of an optical device, includes a first switch adapted to connected to plural light sources on one side and to either a first depolarizer or a polarization controller on the other side thereof. A second switch is connected to both the first depolarizer and the polarization controller on one side and to the device under test on the other side. A detection instrument is connected to the device under test opposite to the second switch. Therefore, a first test path is set up from the light source, the first switch, the first depolarizer, the second switch, the device under test (DUT), to the detection instrument for measuring the pure IL of the DUT without the PDL involved therein, while a second test path is set up from the light source, the polarization controller, the second switch, the DUT, to the detection instrument for measuring the PDL of the DUT.

Abstract: A variable attenuator comprises a motor which actuates a lead screw to move rotatably, and a nut associated with the lead screw to move linearly. A neutral density filter moves along with the linearly moving nut wherein the filter is positioned between two spaced collimators for providing linear attenuation changes of light transmitted therebetween.

Abstract: An optics assembly (10) includes an associated optical fiber (12). A ferrule (14) is formed with an output end (16) of the fiber (12) as a reinforcement interface device for connectively confronting a lens (18). Both the ferrule (14) and the lens (18) are inserted into an resilient split holder (20) from two opposite open ends thereof for self-adjustment and self-alignment between both the ferrule (14) and the lens (18), thus assuring both of them are axially aligned with each other. An enclosure (24) encloses the split holder (20) and the associated ferrule (14) and lens (18), optionally.

Abstract: A filtering assembly includes a first substrate piece and a second substrate piece combined together with their dielectric band-pass filter-film adhered to each other in a face-to-face manner. A corresponding method for making the same includes following steps: (1) providing a raw substrate having at least a twice dimension of final assembly; (2) coating a designated dielectric band-pass filter-film on one side of said raw substrate; (3) dividing said coated substrate into two semi-finished substrate pieces with said filter-film thereon; (4) combining these two semi-finished substrate pieces together wherein said filter-film of one piece is directly adhered to that of another piece by a thin adhesive optical coupling layer, so that the filtering assembly has said filtering means sandwiched between said two substrates.