Abstract: A double stage isolator is formed of face-to-face slabs or sheets of materials that will suitably split, combine, non-reciprocally rotate to ensure isolation in a reverse direction from output ports to respective input ports of any light launched into the input ports. A right angled Porro-prism is disposed at an end of the affixed together slabs having planar faces to direct light launched in a folded fashion to the output ports. A half waveplate is used in addition to beam splitter combiners and non-reciprocal rotators means that rotate the light by 90 degrees so as to pass a single beam in a forward propagating direction and to interchange the polarization of two sub-beams that pass through from an output port to an input port in a reverse direction.

Abstract: A M×N wavelength selective optical switch (WSS) for switching K wavelength channels is disclosed. The WSS has two MEMS micromirror arrays, a M×K array and a 1×N array, for switching any wavelength channel from any input port to any output port, provided that any output port receives optical signals from only one input port. The WSS can be used to build fully reconfigurable, colorless and directionless node of an agile optical network.

Abstract: The multi-unit wavelength switch enables multiple independent wavelength switching of a plurality of incoming multiplexed optical beams simultaneously on the same optical platform. The different units can have similar functionality or provide disparate functionality, e.g. any one or more of switching, dynamic gain equalization, wavelength blocking, and power monitoring.

Abstract: A wavelength selective switch (WSS) based on an array of MEMS mirrors tiltable in 1-dimension about only one axis exhibits “hitting” or unwanted port connections during switching. Two WSS's can be cascaded to create M×N switching functionality in a hitless manner by the inclusion of block ports at specified positions in one or both of the WSS's. Greater use efficiency of ports can be achieved if quasi-hitless performance is acceptable.

Abstract: The invention provides a method of reducing a time-averaged coherence of laser radiation for current-tunable lasers, and a laser apparatus realizing the method, by modulating the laser drive current using a modulation function optimized for obtaining a pre-determined time-averaged spectral profile of the laser radiation. In a preferred embodiment, the pre-determined time-averaged spectral profile has a substantially Gaussian shape. The method is described in reference to laser diodes.

Abstract: Diffractive patterns are disposed on a MEMS substrate in the gaps between the MEMS micromirrors to reduce backreflection of light leaking through the gaps and reflected by the MEMS substrate. The diffractive patterns are silicon surface-relief diffraction gratings or silicon oxide gratings on silicon substrate. Sub-wavelength gratings are used to suppress higher orders of diffraction; 50% duty cycle surface relief gratings on a substrate having index of refraction close to 3 are used to suppress both reflected and transmitted zero orders of diffraction simultaneously. The gratings have lines running parallel or at a slight angle to the gaps, to prevent the diffracted light from re-entering the gaps.

Abstract: The invention provides a method of reducing a time-averaged coherence of laser radiation for current-tunable lasers, and a laser apparatus realizing the method, by modulating the laser drive current using a modulation function optimized for obtaining a pre-determined time-averaged spectral profile of the laser radiation. In a preferred embodiment, the pre-determined time-averaged spectral profile has a substantially Gaussian shape. The method is described in reference to laser diodes.

Abstract: A double stage isolator is formed of a face-to-face slabs or sheets of materials that will suitably split, combine, non-reciprocally rotate to ensure isolation in a reverse direction from output ports to respective input ports of any light launched into the input ports. A right angled Porro-prism is disposed at an end of the affixed together slabs having planar faces to direct light launched in a folded fashion to the output ports. A half waveplate is used in addition to beam splitter combiners and non-reciprocal rotators means that rotate the light by 90 degrees so as to pass a single beam in a forward propagating direction and to interchange the polarization of two sub-beams that pass through from an output port to an input port in a reverse direction.

Abstract: The multi-unit wavelength switch enables multiple independent wavelength switching of a plurality of incoming multiplexed optical beams simultaneously on the same optical platform. The different units can have similar functionality or provide disparate functionality, e.g. any one or more of switching, dynamic gain equalization, wavelength blocking, and power monitoring.

Abstract: A multi-unit wavelength dispersive optical device includes a plurality of independent planar lightwave circuit (PLC) wavelength dispersive optical devices in a single device in which a plurality of independent front and backend units can utilize the same dispersion platform and share the same opto-mechanics and packaging.

Abstract: A single-sided optical switching device for functioning as a dual switch wherein individual switches share common switching means is disclosed. The individual switches have separate ports and share common switching means formed by a moveable refractor, a single lens and a stationary reflector, wherein the movable refractor is positionable between the lens and the stationary reflector for redirecting light within ports of individual switches. An embodiment of the device provides a single-sided dual 2×2 bypass switch comprising a single lens and a single switching element.

Abstract: The invention provides a method of reducing a time-averaged coherence of laser radiation for current-tunable lasers, and a laser apparatus realizing the method, by modulating the laser drive current using a modulation function optimized for obtaining a pre-determined time-averaged spectral profile of the laser radiation. In a preferred embodiment, the pre-determined time-averaged spectral profile has a substantially Gaussian shape. The method is described in reference to laser diodes.

Abstract: A system for determining response characteristics, insertion loss and group delay, of an optical component by applying a sweeping wavelength optical signal that is modulated with an RF signal, measuring the insertion loss and group delay at a series of wavelengths and correlating the measurements to wavelengths. A method for synthesis of an effective modulation frequency in determining the group delay response characteristics of an optical component by obtaining a series of measurements over a sample optical spectrum using a given modulation frequency and calculating a weighted average of the group delays in the series of measurements giving a result substantially equivalent to a measurement taken using a modulation frequency equal to the effective modulation frequency.

Abstract: An optical spectrum analyzer for analyzing at least n wavelengths of light is disclosed having a tunable filter with an input port and an output port and a periodic output response with a free spectral range FSR and having a bandwidth B. An AWG is optically coupled to receive light from the output port; and for distributing the light spatially at other locations in a wavelength dependent manner. Optically coupled with the AWG are m detectors for detecting wavelength or channel information. The number of detectors, m is less than n when a single detector is associated with a single channel; and m is less than 2n when two detectors are associated with a single channel.

Abstract: A method and device is disclosed for relaying a narrow diameter collimated optical beam carrying optical communication signal channels between a multilayer interference filters and another reflective surface avoiding signal loss by routing the optical beam to compensate for beam broadening caused by the multilayer interference filter. The method and device are particularly applicable to dispersion compensating filters, especially those wherein one filter is tunable, in that a controllable amount of dispersion is introduced to offset or compensate dispersion. Preferably one of the filters is a tunable periodic device in the form of a multi-cavity etalon structure. In a preferred embodiment of the filters can be designed to provide various controllable but different constant amounts of dispersion.

Abstract: An optical device for rerouting and modifying an optical signal that uses a double pass through a liquid crystal modulator is disclosed. The optical device includes a first polarizer for providing polarized light, a liquid crystal modulator for selectively modifying the polarized light, a second polarizer for analyzing the light passed through the liquid crystal modulator, and a reflector for reflecting the analyzed light back through the second polarizer, the liquid crystal modulator, and the first polarizer. This arrangement provides a double pass through the liquid crystal modulator, thus significantly improving the attainable extinction ratio.

Abstract: A method and device is disclosed for dispersion compensation of an optical signal having periodic dispersion within a multi-channels system. For example interleaved optical channels often exhibit dispersion having a characteristic that is repeated in adjacent channels. By providing a periodic device that allows for polarization dependent routing of an interleaved signal to allow for multiple passes of said signal through a multi-cavity GT etalon, having a free-spectral range that corresponds to the channel spacing, the dispersion in the interleaved signal can be lessened and practically obviated or balanced to a desired level. This invention provides a device and method to achieve that end.

Abstract: A method and device is disclosed for dispersion compensation of an optical signal having periodic dispersion within a multi-channels system. For example interleaved optical channels often exhibit dispersion having a characteristic that is repeated in adjacent channels. By providing a periodic device in the form of a multi-cavity GT etalon having a free-spectral range that corresponds to the channel spacing the dispersion in the interleaved signal can be lessened and practically obviated or balanced to a desired level. Advantageously, the input and output angle of the signal can be varied to provide fine tuning. This invention provides a device and method to achieve that end.

Abstract: An optical spectrum analyzer for analyzing at least n wavelengths of light is disclosed having a tunable filter with an input port and an output port and a periodic output response with a free spectral range FSR and having a bandwidth B. An AWG is optically coupled to receive light from the output port; and for distributing the light spatially at other locations in a wavelength dependent manner. Optically coupled with the AWG are m detectors for detecting wavelength or channel information. The number of detectors, m is less than n when a single detector is associated with a single channel; and m is less than 2n when two detectors are associated with a single channel.

Abstract: A method and device is disclosed for dispersion compensation of an optical signal. By providing two filters having a sloped dispersion and opposite in sign over a wavelength band wherein one filter is tunable, a controllable amount of dispersion can be introduced to offset or compensate dispersion. Preferably one of the filters is a tunable periodic device in the form of a multi-cavity GT etalon. In a preferred embodiment of the filters can be designed to provide various controllable but different constant amounts of dispersion.