| Patent application number | Description | Published |
|---|
| 20080247429 | Coherence reduction of diode lasers - 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. | 10-09-2008 |
| 20090190202 | MEMS MICROMIRROR DEVICES WITH ANTI-REFLECTIVE STRUCTURES - 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. | 07-30-2009 |
| 20100061727 | HITLESS MxN WAVELENGTH SELECTIVE SWITCH - 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. | 03-11-2010 |
| 20100172646 | M X N WAVELENGTH SELECTIVE OPTICAL SWITCH - 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. | 07-08-2010 |
| 20110170867 | Wavelength Switch - The present invention relates to a wavelength switch including two switching stages. A single actuation array of reflecting elements of a first switching stage routes sub-beams at different wavelength bands to a plurality of actuation arrays of reflecting elements of a second switching stage. Each second-stage actuation array routes sub-beams to a group of output ports associated with that second-stage actuation array. Advantageously, the sub-beams are redirected from the first switching stage to the second switching stage by a reflecting relay assembly, without being combined or coupled into fibers. | 07-14-2011 |
| 20120002917 | M X N WSS WITH REDUCED OPTICS SIZE - A M×N wavelength selective switch (WSS) module capable of independently routing any wavelength channel from any input port to any output port is provided. The M×N WSS includes a first beam relayer including first and second elements having optical power, each of which is disposed such that light transmitted to or from a first plurality of ports passes through a common point. The M×N WSS also includes a wavelength dispersive element, a first switching array having M rows including K switching elements, a second beam relayer, and a second switching array including N switching elements. The second switching array includes an optical by-pass disposed at the common point, which provides means for separating the input and output beams of light, and which allows both the input and output optical beams to traverse similar paths throughout the optical train. | 01-05-2012 |
| 20120057869 | M x N WAVELENGTH SELECTIVE SWITCH (WSS) - An M×N wavelength-selective switch (WSS) is provided. M input ports launch M input beams towards a wavelength-dispersing system, which disperses the M input beams into M×K sub-beams at K wavelength bands. A redirecting system redirects the M×K sub-beams towards a first 1×K switching array, which selects K sub-beams from the M×K sub-beams. The redirecting system blocks the (M−1)×K non-selected sub-beams, but re-images the K selected sub-beams onto a second 1×K switching array by means of at least one relaying element having optical power. The second 1×K switching array routes the K selected sub-beams to N output ports. The redirecting system redirects the K selected sub-beams towards the wavelength-dispersing system, which combines any selected sub-beams that are routed to a same output port. The N output ports then output the K selected sub-beams. | 03-08-2012 |
