Silicon-Photonics Optical Switch with Movable Shunt Waveguide
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current optical switching technologies face challenges in achieving rapid, low-loss, and cost-effective switching solutions for high-port-count optical switches, particularly in telecom and datacom networks, due to high optical loss and path-dependent losses in existing silicon-photonics-based systems.
Innovation Solution
The development of an optical circuit switch with a pair of fixed-position bus waveguides and a movable shunt waveguide that can be optically coupled and decoupled, utilizing a multi-mode interference region to mitigate loss and tapered waveguide regions for reduced optical energy scattering, along with integrated electronics and power monitors for enhanced performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If cascaded 1×2 or 2×2 switches are used to form N×N switch fabrics, then the switch can achieve high port count, but the cumulative optical loss becomes unacceptably high
Solution Approach 1:
The patent divides the optical switch into multiple switching planes, each handling a subset of wavelengths. This segmentation allows each plane to use fewer cascaded switches, reducing cumulative optical loss while maintaining high overall port count capability through wavelength multiplexing across planes.
Solution Approach 2:
The patent introduces a wavelength dimension to the switching architecture, transitioning from spatial switching only to combined spatial-wavelength switching. This allows the system to achieve high port counts by utilizing multiple wavelength channels across multiple switching planes, rather than relying solely on cascaded spatial switches.
2Quantity of substance
If more wavelengths and higher data rates are used to increase network bandwidth, then network capacity increases, but practical and technological barriers make it increasingly difficult to implement
Solution Approach 1:
The patent creates a universal switching platform that can handle multiple wavelengths simultaneously across multiple switching planes. This multi-functional architecture allows the same hardware infrastructure to support increased network bandwidth through wavelength division multiplexing, rather than requiring separate infrastructure for each wavelength or data rate increase.
Solution Approach 2:
The patent utilizes wavelength as a controllable parameter for routing and switching decisions. By changing the wavelength parameter, the system can dynamically reconfigure network paths and capacity without physical reconfiguration, enabling agile bandwidth management while avoiding the technological barriers of traditional single-wavelength systems.
3Speed
If path reconfiguration is performed in the optical domain without conversion to electrical domain, then switching speed improves, but the development of practical fast optical-circuit switches has become challenging
Solution Approach 1:
The patent uses planar lightwave circuit technology to create integrated optical switching paths that can be reconfigured rapidly. The PLC platform allows optical signals to be copied and redirected through different waveguide paths without electrical conversion, achieving fast switching while using mature semiconductor fabrication processes to manage device complexity.
Solution Approach 2:
The patent replaces mechanical or electronic switching mechanisms with integrated optical waveguide-based switching. The PLC technology uses etched waveguides and directional couplers to route optical signals directly in the optical domain, eliminating the need for mechanical movement or electrical-to-optical conversion, thereby achieving fast switching speeds.
4Area of stationary object
If silicon-photonics-based PLC technology is used for high-port-count optical switches, then integration density improves, but the switches exhibit significant optical loss
Solution Approach 1:
The patent segments the optical path into multiple switching planes, each optimized for specific wavelength ranges. This segmentation reduces the number of waveguide crossings and coupling events required in each plane, thereby reducing cumulative optical loss while maintaining high integration density through vertical stacking of planes.
Solution Approach 2:
The patent optimizes different regions of the PLC device for different functions: some regions use adiabatic couplers for low-loss wavelength separation, while other regions use compact directional couplers for switching. This local optimization of coupling regions minimizes overall optical loss while maintaining high integration density throughout the device.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution enables low-loss, rapid, and cost-effective optical switching with minimal path-dependent loss, suitable for various optical circuit switch applications, including OXCs, WXCs, and ROADMs, by concentrating optical energy near the waveguide center and using adiabatic couplers for efficient energy transfer.
Implementation Method 1
utilizing a multi-mode interference region to mitigate loss
Implementation Method 2
tapered waveguide regions for reduced optical energy scattering, along with integrated electronics and power monitors for enhanced performance
Implementation Method 3
a movable shunt waveguide that can be optically coupled and decoupled with the bus waveguides
Data Source
AI summary
An optical switching system comprising a switching cell having first and second fixed-position bus waveguides and a moveable shunt waveguide is disclosed. The first bus waveguide includes an input and a first output. The second bus waveguide includes a second output. When the switching cell is in its unswitched state, the shunt waveguide is not optically coupled with either bus waveguide and a light signal can pass from the input to the first output while remaining in the first bus waveguide. When the switching cell is in its switched state, the shunt waveguide is optically coupled with both bus waveguides such that the light signal is coupled out of the first bus waveguide and into the second bus waveguide via the shunt waveguide. As a result, the light signal can pass from the input to the second output while bypassing the first input.