Alliance Fiber Optic Products, Inc.

Alliance Fiber Optics Products, Inc.

Yuqiao Liu

Wei-Shin Tsay

Peter C Chang

Zhupei Shi

Li Wang

Minh Quang Tran

Yale Zhang

Lee Zhang

Jay Dehkordi

Lin Wu

Gaofeng Chen

Chianchiu Li

Lin T Wang

Techniques for calibrating tunable optical devices using a probing signal as a reference so as to achieve an accurate control over an absolute wavelength of the tunable optical devices. A probing signal being a calibrated optical signal with a spectrum centered at a desired add/drop channel or wavelength is introduced into an N-port circulator coupled between two tunable optical devices. When the two tunable optical devices are tuned not exactly at the desired wavelength, a portion of probing signal will be reflected or dropped out by the two tunable optical devices. The dropped probing signal is detected and coupled to a signal processor or circuitry configured to generate adjustments to or the control signals for controlling the tunable optical devices in accordance with the reflected probing signal being maximized.

Fiber optic tunable add-drop multiplexer/demultiplexer

Optical devices and methods for regulating optical channel signals with specified wavelengths are disclosed. According to one aspect of the present invention, a number of variable optical apparatuses are employed. Each of the variable optical apparatuses includes a first and a second optical channel module, both configured at a wavelength &#x3bb;. Each of the variable optical apparatuses further includes an optical regulator (i.e. a neutral density filter controlled by a stepper motor) coupled between the first and second optical channel modules. When signals with different wavelengths arrive, only the signal with the wavelength &#x3bb;will transmit through the first optical channel module and the rest are reflected off. The transmitted signal is regulated (i.e. attenuated or strengthened) accordingly by the optical regulator before transmitting through the second optical channel module. Hence, the signals with different wavelengths can be respectively regulated by one of the variable optical apparatuses.

Dynamic multi-channel power equalizer and regulator

Improved designs of optical devices for processing optical signals with own or more specified wavelengths are disclosed. According to embodiment, a filter mirror assembly appears an 'L' shape and provides a filtering function as well as a reflecting function. The filter mirror assembly is so mounted that a rotation thereof will not alter the optical path the beam positions of signals resulted from the filter mirror assembly.

Tunable wavelength filter with invariant transmission and reflection beam angles

The inventions invention relates to a generic re-configurable WDM optical cross connection device which may be viewed as an optical network element comprising transport interfaces optionally along with tributary interfaces. An switch system includes a plurality of switch modules each essentially including a pair of R-channel input collimators on one side and a pair of R-channel output collimators on the other side with a switching prism moveably positioned therebetween in an existence/active or non-existence/inactive manner. A pair of input fibers are respectively connected to the two input collimators and an pair of output fibers are respectively connected t the two output collimators. A plurality of jumper fibers cascading said switch modules together.

Optical switch system

Techniques for bonding aligned optical parts to a substrate are disclosed. According to one embodiment, one or more wedges are used to fill in gaps between aligned optical parts and a substrate. Using an appropriate material, the wedges are respectively slid in till respective contacts between the aligned optical parts and the wedges are established, a small amount of a bonding agent is then only applied to the respect contacts. As a result, the shrinkage that may be caused by the bonding agent to destabilize the aligned optical parts is minimized and the alignments among the optical parts are preserved and can sustain under very high environmental stresses.

Method for bonding aligned optical parts and apparatus thereof

Fiber optical interleavers based on a retro-reflective structure are disclosed. The retro-reflective structure includes three stages of optical components. A first stage includes walk-off crystals, at least one of the crystals is used to displace a received optical signal with multiplexed bands or channels therein into a first ray (e.g. an O-ray) and a second ray (e.g. an E-ray). A second stage following the first stage includes at least a pair of birefringent crystals to form an interferometer that create path or phase differences introduced by the birefringent index differences between the first ray and the second ray. A third stage following the second stage includes a pair of half wave plates, a walk-off crystal and a quarter wave plate, wherein the quarter wave plate has a highly reflective coating on one end to retro-reflect light beams back through the same stages. Respective reflected and processed first ray and second ray are then combined in the first stage to output respective demultiplexed beams.

Retro-reflective fiber optic interleaver

Improved designs of optical multiplexing/demultiplexing module are disclosed for use in multiplexing a composite optical signal into respective individual channels or wavelengths or demultiplexing individual channels or wavelengths into a composite optical signal. According to one embodiment, the optical multiplexing/demultiplexing module comprises an array of collimators, an array of optical filters and an array of mirrors. The collimators are boned to a common substrate after being aligned with a respect optical filter. Different from the prior art devices, the aligned positions of the collimators are secured or held up by preformed wedges. A bonding agent is then applied only to respective contacts between the collimators and the wedges. The wedges are further bonded to a common substrate to secure the collimators.

Compact multiplexing/demultiplexing modules

A variable optical attenuator ( ) comprises a dual fiber collimator ( ) and a reflection component ( ) separated by a linear moveable ND filter ( ). The collimator ( ) includes a ferrule ( ) with dual fibers ( ) therein, and a GRIN lens ( ) spaced from the ferrule ( ) with a distance in compliance with the distance between the reflection component ( ) and the GRIN lens ( ).

Dual fiber variable optical attenuator

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

Packaging and sealing of multi-port fiber optic device

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.

Multi-stage optical DWDM channel group interleaver

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.

Retro-reflective multi-port filter device with triple-fiber ferrule

A multi-port fiber optic device ( ) includes a pair of opposite collimators ( ), of which each includes a V-groove dual fiber ferrule ( ) with a GRIN rod lens ( ). At least one band-pass DWDM thin film filter ( ) is securely sandwiched between the two opposite GRIN rod lens ( ) of the pair of collimators ( ). The V-groove dual fiber ferrule ( ) 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 ( ) of the V-groove dual fiber ferrule ( ) will be collimated and transmitted to the DWDM thin film filter ( ). The part of the in-pass-band light will pass through the filter ( ) as performing a demultiplexed channel and is successively coupled into the other collimator ( ) aside.

Multi-port fiber optic device with v-groove ferrule

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 attached next to the other side of the WDM filter ( ) opposite to the lens ( ) after alignment. The triple-fiber ferrule ( ) is used to couple light in and out of the device, and tune the thin film filter center wavelength to the desired ITU grid. Therefore, the coupled-in light from the common input pigtail fiber ( ) of the triple-fiber ferrule ( ) will be collimated and transmitted unto the WDM filter ( ) wherein the part of the in-pass-band light with regard to the WDM filter ( ) will transmit through the WDM filter ( ), and then successively retro-reflect back by the mirror ( ) and further transmit through the WDM band-pass filter ( ) again. The retro-reflected in-pass-band signal is then coupled into one retro-reflective transmission output fiber/port ( ) of the triple-fiber ferrule ( ) as a demultiplexed channel. On the other hand, the out-pass-band light with regard to the WDM filter will not transmit through the WDM filter ( ) to interact with the mirror ( ), but instead be directly reflected back by the WDM filter ( ) and coupled into a reflection output fiber/port ( ) of the triple-fiber ferrule ( ) to be transmitted to the next stage for further demultiplexing other channels.

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

Multi-port fiber optic device with V-groove dual fiber collimator for WDM application

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

Growing community of inventors

Sunnyvale, CA, United States of America

Yuqiao Liu