Oplink Communications Patent Grants

Method for controlling the frequency dependence of insertion loss in an optical assembly

Granted: April 11, 2006
Patent Number: 7027678
A method for controlling the frequency dependence of insertion loss in an etalon-lens-fiber (ELF) optical assembly comprises defining target frequencies and insertion loss objectives therefor and adjusting the optical path length between pairs of the etalon, lens and fiber components until insertion loss objectives are achieved. Insertion loss objectives include insertion loss and insertion loss ripple objectives. The method allows for control of the frequency dependence of insertion…

Integrated high-speed multiple-rate optical-time-division-multiplexing module

Granted: March 7, 2006
Patent Number: 7010230
A novel integrated multiple-rate optical time division multiplexing (OTDM) module is disclosed. An integrated set of modulators generates optical RZ signal streams which are then time-delayed by a set of integrated optical delay switching and combining arrays and interleaved to produce an OTDM signal. The integrated optical delay switching and combining arrays are adapted to be controllably set to various delays to facilitate interleaving of many possible bit-rates. Such an approach…

Chromatic dispersion compensator

Granted: January 31, 2006
Patent Number: 6992823
A chromatic dispersion compensator comprises a beam delay element, such as one or more Gires-Tournois etalon (GTEs); a beam director, such as a polarizing beam splitter (PBS), a prism polarizer, a dielectric polarizer or a crystal polarizer; and a polarization changer, such as one or more quarter-wave plates. The beam director directs an inbound optical beam based on its polarization toward the beam delay element whereat a first unit of group delay is induced. The optical beam traverses…

Optical isolator

Granted: January 17, 2006
Patent Number: 6987896
An optical isolator includes a non-reciprocal combination-device and a reflector. The non-reciprocal combination-device has a principal direction and includes a first birefringent wedge, a second birefringent wedge, and a non-reciprocal rotating element. The non-reciprocal rotating element can be a Faraday rotator. The reflector is positioned proximate to the second birefringent wedge, for reflecting light exiting from the non-reciprocal combination-device in the principal direction to…

Athermal birefringent optical interleavers with flat-top passbands

Granted: January 3, 2006
Patent Number: 6982831
A spectral interleaver providing flat top spectral transmission passbands and athermal operation is disclosed. The spectral interleaver may comprise a pentagon-shaped birefringent crystal, a polarization beam splitter, and a dielectric mirror at one facet of the crystal. Prisms and polarizing beam splitters can be employed for operation with an unpolarized input beam. The cavity formed by the mirror and the crystal serves as a spectrally dispersive mirror. Front mirror reflectivity is…

Auto-setting and optimization of EAM with optical line systems

Granted: November 29, 2005
Patent Number: 6970652
According to the invention there is provided a method of controlling an optical communication system comprising an optical transmitter, an optical receiver and an optical fiber interconnecting the optical transmitter and the optical receiver, the method comprising determining the performance of the optical communication system and controlling at least one setting parameter of the optical transmitter according to the measured performance.

Passive connectivity of waveguides for optical components

Granted: October 18, 2005
Patent Number: 6957004
A packaged waveguide for passive connectivity includes waveguides packaged in a ferrule. The ferrule allows the waveguides to be passively aligned to other waveguides, fibers, or optical components, such as to align a first waveguide in the ferrule with a laser diode in a BiDi. In the exemplary embodiment, a second waveguide in the ferrule the BiDi is at a known and fixed distance apart from the first waveguide at an end face of the ferrule. A detector in the BiDi may be positioned so…

Four-port PM circulator

Granted: October 11, 2005
Patent Number: 6954307
A circulator includes a polarization beam splitter, a first reflector, a first non-reciprocal device, a second non-reciprocal device, and a second reflector. The first reflector is coupled with the polarization beam splitter. The first non-reciprocal device is coupled to the first reflector. The second non-reciprocal device is coupled to the polarization beam splitter. The second reflector is coupled with the polarization beam splitter.

Multi-purpose BER tester (MPBERT) for very high RZ and NRZ signals

Granted: September 27, 2005
Patent Number: 6950972
A multi-purpose bit error rate tester (MPBERT) and a method of bit error rate (BER) testing of electrical and optical components and subsystems of electrical and optical communications systems is provided. The invention provides for bit error rate testing both in the optical and the electrical domain, and for bit error rate testing at higher than achievable rates in the electrical domain by multiplexing and demultiplexing in the optical domain. An MPBERT constructed according to the…

Ultra broadband capacitor assembly

Granted: September 13, 2005
Patent Number: 6944009
Systems and apparatuses for providing a broadband capacitor assembly. One broadband capacitor assembly includes a first capacitor operable to provide a first end of an operational band of frequencies within an operational band of a broadband capacitor assembly. The broadband capacitor assembly also includes a second capacitor coupled in parallel to the first capacitor, the second capacitor operable to provide a second end of the operational band of frequencies within the operational band…

Optical assembly and method for fabrication thereof

Granted: August 23, 2005
Patent Number: 6932521
An optical assembly includes a fiber optic pigtail, a sleeve in which the pigtail is housed, a collimating lens, a rod upon which is mounted an optical device and a lens sleeve in which the lens and rod are housed. Bonding lines bond the rod and lens to the lens sleeve, the pigtail to the pigtail sleeve, and the pigtail sleeve to the lens sleeve. The optical assembly and method of fabrication thereof support multiple optical device geometries, longitudinal adjustment of the position of…

System and method for optical multiplexing and/or demultiplexing

Granted: July 5, 2005
Patent Number: 6914676
Improved methods and systems for routing and aligning beams and optical elements in an optical device include a multiplexing device and/or a demultiplexing device, which includes an optical alignment element (OAE). The OAE can be configured to substantially compensate for the cumulative alignment errors in the beam path. The OAE allows the optical elements in a device, other than the OAE, to be placed and fixed in place without substantially compensating for optical alignment errors. The…

Variable optical attenuator with MEMS devices

Granted: July 5, 2005
Patent Number: 6915061
A variable optical attenuator includes a first lens, a MEMS device, a second lens, and a wedge. The first lens is configured to collimate an input light received on a first port and focus an output light on a focus point proximate to a second port. The MEMS device includes a reflection surface having a tilting angle thereof controllable by a control variable. The second lens has a focus point positioned proximate to the reflection surface of the MEMS device. The wedge is positioned…

Integrated two-pump combiner for optical fiber amplifiers

Granted: May 31, 2005
Patent Number: 6900933
An integrated optical fiber amplifier system includes a non-reciprocal combination-device and an optical fiber amplifier. The non-reciprocal combination-device includes a first birefringent wedge, a second birefringent wedge, and a non-reciprocal rotating element. The optical fiber amplifier is optically coupled to the first birefringent wedge for receiving a combined pump light from the non-reciprocal combination-device.

Single chip ASIC and compact packaging solution for an avalanche photodiode (APD) and bias circuit

Granted: May 17, 2005
Patent Number: 6894266
A compact integrated APD device integrates the bias voltage and temperature compensation functions inside a standard 4-pin PIN package. The active components of the bias and temperature compensation circuits are integrated into a single ASIC using a high-voltage CMOS process and operated at frequencies of at least 1 MHz to greatly reduce the size of the passive components. To mount the relatively large ASIC chip inside the package with the APD chip, TIA chip and passives, the 4-pin…

Optical circulator

Granted: May 17, 2005
Patent Number: 6895129
An optical circulator has a first collimator; a first block of birefringent material; a first compound polarization rotator; a light angle deflector (e.g., Wollaston prism); a second compound polarization rotator; a second block of birefringent material; and a second collimator. Light from the first fiber exits the first collimator along a first path into a first collimated beam that first hits the central plane on a crossing line between the interface and the central plane such that the…

Multi-port circulator

Granted: May 3, 2005
Patent Number: 6888971
An extendable four-port circulator includes a middle birefringent crystal, a first birefringent crystal, a first non-reciprocal device, a second birefringent crystal, and a second non-reciprocal device. The first non-reciprocal device is coupled to the first birefringent crystal. The second non-reciprocal device is coupled to the second birefringent crystal. The middle birefringent crystal includes a first surface, a second surface, a third surface, and a fourth surface. The first…

Four-port PM circulator

Granted: April 19, 2005
Patent Number: 6882759
A four-port circulator includes a first birefringent crystal, a structured polarization rotator, a first birefringent wedge, a second birefringent crystal, a non-reciprocal device, and a second birefringent wedge. The structured polarization rotator is coupled to the first birefringent crystal. The first birefringent wedge is coupled to the structured polarization rotator. The second birefringent crystal is coupled to the first birefringent wedge. The non-reciprocal device is coupled to…

Miniature 2×2 magneto-optic switch

Granted: April 12, 2005
Patent Number: 6879746
A magneto-optical switch includes a first birefringent crystal configured to receive a light beam, a first half-wave compensator plate pair configured to receive split light beams from the birefringent crystal, a first Faraday rotator configured to receive the split light beams from the first half-wave compensator plate pair, and a beam splitter configured to receive the split light beam from the Faraday rotator. The first Faraday rotator is configured to change the polarization of a…

Three-port circulator

Granted: March 29, 2005
Patent Number: 6873462
A three-port circulator includes a non-reciprocal rotating element, a first birefringent wedge, and a second birefringent wedge. The non-reciprocal rotating element has a rotation axis and rotates the polarization of light passing through it by an predetermined angle. The first birefringent wedge has a first optical axis substantially perpendicular to the rotation axis. The second birefringent wedge has a second optical axis substantially perpendicular to both the rotation axis and the…