Polarisation-Maintaining Optical Switch for Power-Efficient Buffering

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional optical buffering in medical imaging systems, such as OCT, results in significant power loss due to the recombination of optically buffered signals using 50/50 couplers, leading to reduced system sensitivity and image quality.

Innovation Solution

The implementation of an optical switch that toggles between buffered and non-buffered signals, redirecting each signal to a single output, eliminating power loss by sequentially gating multiple optical paths to a single output port.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If 50/50 couplers are used to recombine optically buffered signals, then optical buffering can be achieved to increase effective imaging speed, but significant power loss occurs reducing system sensitivity and image quality

Engineering Contradiction:
Improveeffective imaging speedVSAvoidoptical power loss
Core Design Contradiction:
SpeedVSLoss of energy

Solution Approach 1:

The patent employs dynamic optical switching to selectively route buffered and non-buffered signals in time-varying sequences. The optical switch dynamically changes its state to direct different optical paths to the output at different times, enabling flexible signal combination without fixed 50/50 power division. This dynamic routing achieves effective imaging speed enhancement while preserving optical power by ensuring 100% of signal power reaches the output during each time slot.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent implements periodic switching between buffered and non-buffered signal paths at synchronized intervals. By alternating between different optical path configurations in a periodic manner matched to the imaging sequence, the system achieves time-averaged speed enhancement while maintaining consistent power delivery. The periodic switching ensures that during each imaging frame, the appropriate signals are routed without power loss.

Inventive Principle:
Principle #19Periodic action

2Speed

If conventional optical buffering is used to increase imaging speed, then effective imaging speed beyond native source speed is achieved, but system sensitivity and image quality deteriorate due to power loss

Engineering Contradiction:
Improveimaging speedVSAvoidimage quality
Core Design Contradiction:
SpeedVSMeasurement precision

Solution Approach 1:

The optical switch dynamically routes signals to preserve power, and the polarization controller actively maintains optimal polarization states throughout the optical paths. This dynamic adaptation ensures that image quality is preserved despite the complex time-varying signal routing required for speed enhancement. The system adjusts polarization parameters in real-time to compensate for any polarization-related signal degradation.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the polarization state parameters of optical signals using a polarization controller to maintain optimal signal characteristics through the buffering system. By adjusting polarization parameters, the system ensures consistent signal quality regardless of the buffering path taken, thereby maintaining image quality while achieving speed enhancement through optical buffering.

Inventive Principle:
Principle #35Parameter changes

3Speed

If optical signals are split into multiple paths for buffering, then effective imaging speed is increased, but power loss occurs during recombination reducing signal-to-noise ratio

Engineering Contradiction:
Improveeffective imaging speedVSAvoidsignal-to-noise ratio
Core Design Contradiction:
SpeedVSLoss of information

Solution Approach 1:

The optical switch dynamically selects which buffered or non-buffered signal path to connect to the output at any given time, ensuring that 100% of the optical power from the active path reaches the detector without division loss. This dynamic time-division multiplexing approach preserves signal-to-noise ratio by avoiding the continuous power division inherent in simultaneous multi-path recombination, while still achieving effective speed enhancement through the buffering architecture.

Inventive Principle:
Principle #15Dynamics

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 approach enhances signal-to-noise ratios and image resolution by ensuring that 100% of the optical power is directed to the OCT interferometer, improving imaging quality and reducing power loss compared to traditional buffering methods.

Implementation Method 1

an optical switch for recombining buffered and non-buffered optical signals transmitted through the optical circuit, the optical switch having two input ports and a single output port, the optical switch being a polarisation-maintaining optical switch

Methodology Applied
Scientific EffectPolarisation: Polarisation

Data Source

PatentEP2936241B1Power-efficient optical buffering using a polarisation-maintaining active optical switch
Publication Date: 2020.10.21 KEMP NATHANIEL J
  • EP2936241B1 patent drawingFigure 1
  • EP2936241B1 patent drawingFigure 2
  • EP2936241B1 patent drawingFigure 3

AI summary

The present invention generally relates to optical circuits for mitigating power loss in medical imaging systems and methods for using such circuits. Circuits of the invention can involve a first optical path, a second optical path, and a means for recombining an optical signal transmitted through the first and second optical paths by sequentially gating the first and second optical paths to a single output.