Optical Circuit Common Ground Resistor Thermal Crosstalk

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Thermal crosstalk between densely arranged optical interference circuits in optical transmission/reception devices becomes significant when devices are downsized and channels are increased, affecting the performance of these devices.

Innovation Solution

Incorporating a resistor element connected to the thermo-optical phase shifters of neighboring optical interference circuits to share an electrical path, allowing for voltage or thermal feedback to cancel out thermal crosstalk components, thereby reducing the adverse effects of heat transfer between circuits.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the number of channels of high-frequency electric signal for one channel of light is increased and optical transmission/reception devices are downsized, then transmission capacity per unit volume is enlarged, but thermal crosstalk between optical interference circuits becomes larger

Engineering Contradiction:

Improvetransmission capacity per unit volumeVSAvoidthermal crosstalk

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The invention divides the electrical path into multiple segments by introducing intermediate potential terminals between the high-frequency electric signal application terminals and the common potential terminal. This segmentation allows for independent control of voltage distribution across different optical interference circuits, enabling compensation for thermal crosstalk effects while maintaining device downsizing and high channel density.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The invention implements a feedback mechanism where voltage is applied to specific terminals to generate compensating thermal effects. By controlling the voltage distribution across segmented electrical paths, the system creates feedback loops that counteract thermal crosstalk between neighboring optical interference circuits, thereby maintaining performance despite increased circuit density.

Inventive Principle:

Principle #23Feedback

2Volume of moving object

If the distance between optical interference circuits becomes shorter, then device size is reduced, but thermal crosstalk between circuits increases

Engineering Contradiction:

Improvedevice sizeVSAvoidthermal crosstalk

Core Design Contradiction:

Volume of moving objectVSObject-affected harmful factors

Solution Approach 1:

The electrical path is segmented into multiple sections with intermediate potential terminals, allowing independent voltage control for each optical interference circuit. This enables compensation of thermal crosstalk effects even when circuits are densely packed at short distances, thereby achieving device downsizing without sacrificing performance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The invention changes the electrical parameters (voltage distribution) across the segmented electrical paths to compensate for thermal crosstalk. By adjusting voltage levels at intermediate terminals, the system dynamically compensates for thermal effects that increase with shorter circuit distances, maintaining optimal performance in compact device configurations.

Inventive Principle:

Principle #35Parameter changes

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 reduces thermal crosstalk between neighboring optical interference circuits, maintaining performance and enabling the downsizing of optical transmission/reception devices while enhancing communication capacity.

Implementation Method 1

a resistor element connected to the other end of the first thermo-optical phase shifter and the other end of the second thermo-optical phase shifter, through which a current from each of the first thermo-optical phase shifter and the second thermo-optical phase shifter flows toward a common potential

Methodology Applied

Scientific EffectElectrical conduction: Conduction (electrical)

Implementation Method 2

A control voltage Vcont1 is applied to a voltage application terminal 103a so that current flows through the thermo-optical phase shifter 102a and heat generates, thereby changing the refractive index of the arm waveguide and shifting (changing) the phase of branched light 11b

Methodology Applied

Scientific EffectJoule heating: Joule Heating

Data Source

PatentUS12099266B2Optical circuit with common ground configuration for resistors and thermo-optic phase shifters

Publication Date: 2024.09.24 NIPPON TELEGRAPH & TELEPHONE CORP

AI summary

An optical circuit of the present disclosure shares at least a part of an electrical path including phase variable means between neighboring optical interference circuits, or configures an electrical path so as to straddle neighboring optical interference circuits, thereby performing electrical or thermal feedback. The optical circuit includes a mechanism using the electrical or thermal feedback for cancelling components of thermal crosstalk from one optical interference circuit to another neighboring optical interference circuit. The optical circuit of the present disclosure has a resistor element that shares electrical paths including respective phase variable means between the neighboring optical interference circuits. The optical circuit changes the phase change amount by the phase variable means in the neighboring optical interference circuit, in such a way as to cancel the thermal crosstalk components by the resistor element.