Abstract: Techniques and devices for modulating an optical signal transmitting through an optical waveguide such as a fiber and a planar waveguide by dynamically controlling an adjustable grating formed in a cladding layer of the waveguide.

Abstract: Techniques and devices for forming a controllable thermal grating in an optical waveguide.

Abstract: Systems and techniques of incorporating an optical resonator in an optical part of a feedback loop in opto-electronic oscillators. This optical resonator provides a sufficiently long energy storage time and hence to produce an oscillation of a narrow linewidth and low phase noise. Certain mode matching conditions are required. For example, the mode spacing of the optical resonator is equal to one mode spacing, or a multiplicity of the mode spacing, of an opto-electronic feedback loop that receives a modulated optical signal and to produce an electrical oscillating signal.

Abstract: Techniques for reducing frequency shifts in an oscillating frequency of an opto-electronic oscillator by having at least two separate optical delay elements in an optical portion of an opto-electronic feedback loop.

Abstract: Techniques and devices for depolaring polarized light by using one or more birefringent optical elements in the optical path of light to scramble the state of polarization of light. Examples of devices for coupling with a fiber or a fiber device, and their applications in various fiber environments are also described.

Abstract: Systems and techniques for suppressing the carrier signal using an optical delay element and an electrical interferometer in an opto-electronic noise suppression module.

Abstract: Techniques for dynamically controlling polarization of an optical signal by combining both feed-forward and feedback controls.

Abstract: Systems and techniques of incorporating an optical resonator in an optical part of a feedback loop in opto-electronic oscillators. This optical resonator provides a sufficiently long energy storage time and hence to produce an oscillation of a narrow linewidth and low phase noise. Certain mode matching conditions are required. For example, the mode spacing of the optical resonator is equal to one mode spacing, or a multiplicity of the mode spacing, of an opto-electronic feedback loop that receives a modulated optical signal and to produce an electrical oscillating signal.

Abstract: Implementations of a polarization control method and apparatus are provided. In one implementation, a device uses super-polished squeezing surfaces to apply pressure against a polyimide coated fiber thereby minimizing micro-bending effects that cause losses in the fiber. Special control circuitry may be used to maintain a driving source of piezo-electrics that control the squeezing surfaces at a resonant frequency, thereby minimizing the voltages needed to drive the piezo-electrics.

Abstract: Opto-electronic devices and techniques using Brillouin scattering to select a sideband in a modulated optical carrier signal for amplification. Two lasers respectively provide a carrier signal beam and a Brillouin pump beam which are fed into an Brillouin optical medium in opposite directions. The relative frequency separation between the lasers is adjusted to align the frequency of the backscattered Brillouin signal with a desired sideband in the carrier signal to effect a Brillouin gain on the sideband. This effect can be used to implement photonic RF signal mixing and conversion with gain, conversion from phase modulation to amplitude modulation, photonic RF frequency multiplication, optical and RF pulse generation and manipulation, and frequency-locking of lasers.

Abstract: Depolarizing system for polarized light formed of a birefringence crystal wedge which receives the beam of polarized light at a first surface and outputs spatially depolarized light from its output surface. The wedge may include small steps on one of the surfaces or special orientations to depolarize the light. The wedge may be substantially triangular in shape so that the surface decreases from one side to the other.

Abstract: An improved polarization control method and apparatus is provided. The described invention uses super-polished squeezing surfaces to apply pressure against a polyimide coated fiber thereby minimizing micro-bending effects that cause losses in the fiber. Special control circuitry has also been designed to maintain a driving source of piezo-electrics that control the squeezing surfaces at a resonant frequency, thereby minimizing the voltages needed to drive the piezo-electrics.

Abstract: A system of coupling optical energy in a waveguide mode, into a resonator that operates in a whispering gallery mode. A first part of the operation uses a fiber in its waveguide mode to couple information into a resonator e.g. a microsphere. The fiber is cleaved at an angle &PHgr; which causes total internal reflection within the fiber. The energy in the fiber then forms an evanescent field and a microsphere is placed in the area of the evanescent field. If the microsphere resonance is resonant with energy in the fiber, then the information in the fiber is effectively transferred to the microsphere.

Abstract: Devices that couple variable attenuators to a single WDM multiplexer to individually adjust and control the power levels of different WDM channels, e.g., substantially equalizing the power levels of the channels. Optical reflection and in-fiber variable attenuators are implemented to simplify the device structure and reduce cost.

Abstract: An improved polarization control method and apparatus is provided. The described invention uses super-polished squeezing surfaces to apply pressure thereby minimizing micro-bending effects that cause losses in the fiber. Special control circuitry has also been designed to maintain a driving source of piezo-electrics that control the squeezing surfaces at a resonant frequency, thereby minimizing the voltages needed to drive the piezo-electrics.

Abstract: Techniques for producing optical pulses based on Brillouin selective sideband amplification by using a common modulation control signal to modulate both a signal beam to produce multiple sideband signals and a single pump beam to produce multiple pump beams.

Abstract: Techniques and devices to modulate light by using a whispering gallery mode optical resonator exhibiting an electro-optic effect. An electrical signal is coupled into the optical resonator to change a dielectric constant of optical resonator and thus to modulate the optical output from the optical resonator.

Abstract: Techniques for reducing frequency shifts in an oscillating frequency of an opto-electronic oscillator by having at least two separate optical delay elements in an optical portion of an opto-electronic feedback loop.

Abstract: Systems and techniques for transmitting and processing an electrical signal through an opto-electronic system with an optical Brillouin amplifier.

Abstract: A wavelength converter including a chip having formed therein a first electro-absorption modulator biased as a photodetector, and a second electro-absorption modulator biased as a modulator electrically coupled to the first electro-absorption modulator. The first electro-absorption modulator detects an input signal at wavelength &lgr;1 and generates an electrical signal to control the second electro-absorption modulator's modulation of light from a wave source at wavelength &lgr;2.