WDM Optical Switch Beam Profile Shaping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wavelength division multiplexed (WDM) optical switches face challenges with crosstalk and reduced beam energy due to beam spreading, especially when multiple switches are cascaded, leading to increased bit error rates and undesirable roll-off in frequency response.
Innovation Solution
A reconfigurable optical switch with a diffractive element and a holographic array that modifies the transverse beam profile to a flattened or steeper-sided shape, better fitting a rectangular envelope, to improve beam alignment and reduce crosstalk, combined with a method for secure routing using a matched spatial filter and key phase pattern for enhanced security.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If beam propagation is allowed to spread naturally through the optical switch, then the beam covers the entire sub-hologram area, but this causes beam energy reduction and increased crosstalk when multiple switches are cascaded
Solution Approach 1:
The patent applies local quality by creating a beam profile that is locally optimized with enhanced energy concentration in the central region and suppressed edges. This is achieved through beam profiling optical elements that modify the transverse beam profile to have steeper sides and a flattened top, concentrating beam energy where it is needed while reducing energy at the edges that would cause crosstalk in cascaded switches.
2Reliability
If the beam profile is modified to a flattened shape with steeper sides, then beam alignment and energy concentration improve, but additional optical elements are required
Solution Approach 1:
The patent merges multiple functions into integrated optical elements. The beam profiling optical elements are positioned to work in conjunction with the existing diffractive elements and holographic arrays, combining beam profile modification with wavelength demultiplexing and spatial dispersion functions. This integration approach reduces the need for completely separate optical subsystems while achieving the desired beam profile modification.
3Productivity
If multiple cascaded switches are used to increase routing capacity, then data handling capability improves, but beam spreading accumulates and increases bit error rates
Solution Approach 1:
The patent applies preliminary action by modifying the beam profile before it enters the cascaded switch system. The beam profiling optical elements prepare the beam with an optimized transverse profile that anticipates and prevents the accumulation of beam spreading effects that would occur through multiple cascaded switches. This preliminary optimization ensures that even after passing through multiple switches, the beam maintains sufficient energy concentration and alignment to avoid increased bit error rates.
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
The solution effectively mitigates crosstalk and bit error rates, enhances data handling capacity, and improves the security of WDM optical switches by optimizing beam profiles and using secure routing techniques.
Implementation Method 1
at least one diffractive element on an optical path between at least one optical input port and said reconfigurable holographic array, to demultiplex said WDM input optical signal into a plurality of demultiplexed optical input beam channels
Implementation Method 2
a reconfigurable holographic array on an optical path between said at least one optical input port and said plurality of optical output ports... wherein a sub-hologram is configured to direct a demultiplexed optical input beam channel to a respective selected one of said optical outputs
Data Source
Figure 1a~1d
Figure 2
Figure 3
AI summary
We describe a wavelength division multiplexed (WDM) reconfigurable optical switch, the switch comprising: at least one optical input port to receive a WDM input optical signal comprising a plurality of wavelength channels; a plurality of optical output ports;a reconfigurable holographic array on an optical path between said at least one optical input port and said plurality of optical output ports; and at least one diffractive element on an optical path between at least one optical input port and said reconfigurable holographic array, to demultiplex said WDM input optical signal into a plurality of demultiplexed optical input beam channels, and to disperse said demultiplexed optical input beam channels spatially along a first axis on said reconfigurable holographic array; wherein said reconfigurable holographic array comprises an array of configurable sub-holograms, said array extending along said first axis, wherein a sub- hologram is configured to direct a demultiplexed optical input beam channel to a respective selected one of said optical outputs; and wherein the switch further comprises one or more beam profiling optical elements to modify transverse beam profiles of said demultiplexed optical input beam channels to a said beam profile and/or steepen its sides and/or modify the profile so that it better fits a rectangular envelope.