Oclaro (North America Inc.)

Avanex Corporation

Other

Ii-Vi Incorporated

Oclaro Technology Limited

Christopher Lin

Giovanni Barbarossa

Xuehua Wu

Haijun Yuan

Simon Xiaofan Cao

Martin Richard Williams

Xuefeng Yue

Douglas Llewellyn Butler

Simon X F Cao

Peter Gerard Wigley

Ruibo Wang

Ruipeng Sun

Yongsheng Liu

Deepak Devicharan

Ming Cai

Jialing Yang

Mark Summa

Eric Chiu Tat Cheung

Charlene Yang

Jiyong Ma

Younsheng Liu

An optical switch for performing high extinction ratio switching of an optical signal includes a beam polarizing element and one or more optical elements. The optical elements are configured to direct an optical signal along a first or second optical path based on the polarization state of the optical signal as it passes through the optical elements. The optical switch performs high extinction ratio switching of the optical signal by preventing unwanted optical energy from entering an output port by using an absorptive or reflective optical element or by directing the unwanted optical energy along a different optical path.

High extinction ratio liquid crystal optical switch

An optical device is configured to perform both switching and attenuation of an optical beam in response to a single control signal. The optical device includes a liquid-crystal-based beam-polarizing element having polarization-conditioning regions that are controlled using a common electrode. The first polarization-conditioning region conditions the polarization of the input beam in order to separate the input beam into a primary component and a residual component. The second and third polarization-conditioning regions change the polarization of the primary component and the residual component, respectively. The primary component is directed to an output port after it has been attenuated based on its polarization state. The residual component, after passing through the third polarization-conditioning region, has its intensity further reduced based on its polarization state.

Single control liquid crystal optical switch and attenuator

An optical device for a wavelength division multiplexing system has a telecentric lens system and a signal-processing optical element, where the signal-processing optical element performs switching, attenuation, or other optical signal processing for the optical device. The telecentric lens system acts as a self-compensating optical system to minimize sensitivity of the optical device to unwanted displacement of an input image from the optical axis of the optical device. The optical device may include multiple telecentric lens systems, in which case the optical device is also less sensitive to precise alignment between the telecentric lens systems.

Optical device with stable optical configuration

Described are Gain Flattening Filters (GFFs) implemented using mechanical translating assemblies to move selected thin film Gain Attenuating Filters (GAFs), and combinations of selected GAFs, into or out of the output path from an optical amplifier. The GAFs may be used singly, or in combinations that synthesize many target filter characteristics. The GFF is primarily adapted for WDM systems operating with a wavelength range of approximately 1520 nm to 1620 nm. Several embodiments are shown for effectively combining different GAFs to provide multiple GFF curves.

Optical amplifiers using switched filter devices

A fiber lens assembly is configured to optically couple an optical fiber to a signal processing device having free-space optical elements. The fiber lens assembly includes a diverging lens having a focal length that may be around 2 to 6 times the diameter of the optical fiber core. Sensitivity of the fiber lens assembly to angular misalignment and positional displacement is reduced by coupling the optical fiber to the signal processing device using a diverging lens rather than a collimating lens, and by configuring the diverging lens with a suitable focal length.

Fiber lens assembly for optical device

An optical device has the structure to perform switching and attenuation of an optical beam with reduced polarization dependent loss (PDL). The optical device includes a birefringent displacer and two liquid crystal (LC) structures. The first LC structure is used to condition s-polarized components of the optical beam and the second LC structure is used to condition p-polarized components of the optical beam. Each LC structure has a separate control electrode so that the s-polarized components of the optical beam and the p-polarized components of the optical beam can be conditioned differently and in such a manner that reduces PDL. The optical device may be configured for processing multiple input light beams, such as the multiple wavelength channels de-multiplexed from a wavelength division multiplexed (WDM) optical signal.

Liquid crystal optical switch configured to reduce polarization dependent loss

The specification describes optical performance monitors which are simplified by coupling single tunable optical filters to multiple channels being monitored. Optical measurements for more than one channel may be made simultaneously. The optical system architecture is preferably an optical performance monitor for a WDM system. In a system designed according to the invention n channels may be monitored using n photodetectors, n optical splitters, but only n/2 tunable optical filters. Additional system simplification may be obtained using optical switching elements coupled to the optical splitters.

Wavelength division multiplexed systems with optical performance monitors

One embodiment sets forth a technique for measuring chromatic dispersion using reference signals within the operational range of amplifiers used to refresh data signals. One red/blue laser pair in the transmission node is used for measuring dispersion and chromatic dispersion compensation is added at each line node in the system. Since reference and data signals propagate through each amplifier, the reference signals used to measure chromatic dispersion receive the same dispersion compensation (and will have the same residual dispersion) as the data signals. Therefore, any residual dispersion in the data signals will manifest itself in downstream dispersion measurements and, thus, can be corrected. The tunable dispersion compensator in each line node may be set to compensate for the measured dispersion, thereby compensating for both the chromatic dispersion of the link connecting the current node to the prior node and any uncorrected residual dispersion from prior nodes.

System and method for tunable chromatic dispersion compensation

The specification describes an optical wavelength monitor/analyzer that uses a cost effective wavelength reference source. The wavelength reference source is a nominally fixed wavelength laser with inherent tunability over a very limited wavelength range, i.e. a few nanometers. Tuning is effected by changing the temperature of the laser. The limited range is useful for making multiple wavelength measurements in the context of analyzing wavelength drift in tunable optical filters.

Analyzing tunable optical filters using tunable source

A tunable chromatic dispersion and dispersion slope compensator that utilizes a Virtually Imaged Phased Array (VIPA), a rotating transmissive diffraction grating, and a mirror with different curvatures for different cross-sections is disclosed. The compensator in accordance with the present invention provides simultaneous tunable compensation of chromatic dispersion and dispersion slope utilizing a single apparatus. The amount of compensation is accomplished by rotating the transmissive diffracting grating and/or translating the mirror. A system which utilizes the compensator is thus cost effective to manufacture.

Tunable chromatic dispersion and dispersion slope compensator utilizing a virtually imaged phased array and a rotating grating

The present invention provides an improved gain slope equalizer which provides variable optical attenuation. The gain slope equalizer includes a transmission diffraction grating with a first side and a second side; a first lens optically coupled to the second side of the transmission diffraction grating; and at least one reflective surface optically coupled to the first lens at a side opposite to the transmission diffraction grating. The gain slope equalizer in accordance with the present invention can also be used with a Virtually Imaged Phased Array (VIPA) to provide a chromatic dispersion slope and chromatic dispersion compensation as well as variable optical attenuation. The present invention provides the heretofore unavailable capability of simultaneous tunable gain slope equalization and chromatic dispersion compensation utilizing a single apparatus.

Method, apparatus, and system for compensation of amplifier gain slope and chromatic dispersion utilizing a virtually imaged phased array

A dynamic gain equalizer (DGE) includes: a mirror; an electrode; and a lever with a first end and a second end opposite to the first end, where the lever is capable of rotating about a fulcrum, where the lever rotates the first end toward the electrode when the electrode is charged such that the second end blocks a portion of a channel from reaching the mirror, where an unblocked portion of the channel is reflected by the mirror. By manipulating the charge on the electrode, the rotation of the lever is controlled, determining how much of the light is blocked by the lever. Each lever in an array can attenuate a channel or a group of channels of a composite optical signal by a different amount. The DGE provides a significant range of blockage and can be closely spaced. It provides ease in integrating channel monitoring into the DGE.

MEMS see-saw array for dynamic gain equalization of DWDM systems

The present invention provides a dispersion compensator which utilizes a Virtually Imaged Phased Array (VIPA), gratings, and birefringent wedges to moderate chromatic dispersion, dispersion slope and polarization mode dispersion, and a method and system for testing such a dispersion compensator. The dispersion compensator in accordance with the present invention propagates the composite optical signal in a forward direction; separates the wavelengths in the band of wavelengths in each of the plurality of channels, where each of the wavelengths in the band is spatially distinguishable from the other wavelengths in the band; spatially separates each band of wavelengths in the plurality of channels; spatially separates each wavelength of each separated band of wavelengths into a plurality of polarized rays; and reflects the plurality of polarized rays toward a return direction, where dispersion is added to the reflected plurality of polarized rays such that the unwanted chromatic dispersion, dispersion slope, and PMD are compensated. The dispersion compensator provides simultaneous tunable compensation of these various dispersions utilizing a single apparatus. A system which utilizes the compensator is thus cost effective to manufacture. Systems may be provides which determines the operating and performance parameters for the compensator, and measures the spectrum outputted by the compensator.

Method and system for testing a tunable chromatic dispersion, dispersion slope, and polarization mode dispersion compensator utilizing a virtually imaged phased array

Growing community of inventors

El Cerrito, CA, United States of America

Christopher Lin