Broadband Light Source Pulse Switching for Nonlinear Fiber Lifetime

Solution Overview

Problem

Existing broadband light sources face limitations such as low intensity, low brightness, and challenges in coupling light into fibers, leading to mediocre quality, and power degradation issues in nonlinear fibers.

Innovation Solution

A light source with a pulse generator and optical arms that allow switching between high-power and low-power modes by varying the number of pulses per time period, using a modulator and nonlinear optical element to generate a broadband spectrum while controlling peak power to prevent degradation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If high power light pulses are propagated through a nonlinear fiber to generate broadband spectrum, then the spectral bandwidth and intensity are improved, but the nonlinear fiber experiences power degradation and reduced lifetime

Engineering Contradiction:

Improvelight intensityVSAvoidnonlinear fiber lifetime

Core Design Contradiction:

Illumination intensityVSReliability

Solution Approach 1:

The system uses periodic pulse trains with controlled repetition rates to generate broadband spectrum through nonlinear optical effects while allowing the fiber to cool and recover between pulse sequences, reducing cumulative degradation

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The system dynamically adjusts the pulse repetition rate and duty cycle based on operating conditions, switching between high-power short-duration modes for spectrum generation and lower-power modes for sustained operation, optimizing both intensity and fiber lifetime

Inventive Principle:

Principle #15Dynamics

2Illumination intensity

If broadband light is generated through supercontinuum generation, then the spectral bandwidth is improved, but the spatial coherence and coupling efficiency into fiber are worsened

Engineering Contradiction:

Improvespectral bandwidthVSAvoidcoupling efficiency

Core Design Contradiction:

Illumination intensityVSEase of operation

Solution Approach 1:

The system uses mode-field adaptors and tapered fibers that locally modify the beam profile at specific points in the optical path, transforming the spatial distribution to match fiber acceptance modes while preserving the broadband spectral characteristics

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The system introduces intermediate optical components such as mode-field adaptors and lens systems between the nonlinear fiber output and the target fiber input, serving as mediators that transform beam characteristics to improve coupling efficiency without affecting the generated spectrum

Inventive Principle:

Principle #24Intermediary (Mediator)

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

Enables high-power operation with minimal degradation, allowing for versatile applications in spectroscopy and optical coherence tomography with extended lifetime and improved spectral characteristics.

Implementation Method 1

The term supercontinuum does not cover a specific phenomenon but rather can include at least some of plethora of nonlinear effects, such as self-phase modulation, Raman scattering, phase matching and soliton generation, leading to considerable broadening of optical pulses

Methodology Applied

Scientific EffectSelf-phase modulation:

Implementation Method 2

The term supercontinuum does not cover a specific phenomenon but rather can include at least some of plethora of nonlinear effects, such as self-phase modulation, Raman scattering, phase matching and soliton generation, leading to considerable broadening of optical pulses

Methodology Applied

Scientific EffectRaman scattering:

Implementation Method 3

The term supercontinuum does not cover a specific phenomenon but rather can include at least some of plethora of nonlinear effects, such as self-phase modulation, Raman scattering, phase matching and soliton generation, leading to considerable broadening of optical pulses

Methodology Applied

Scientific EffectSoliton generation: Soliton

Data Source

PatentUS12379641B2Light source

Publication Date: 2025.08.05 NKT PHOTONICS AS

AI summary

A light source including: a pulse generator for providing an initial sequence of light pulses, the pulse generator including an optical source for producing optical pulses; a modulator in communication with the optical source for increasing or decreasing the selected number of pulses provided by the pulse generator in the selected time period; first and second optical arms, for propagating, respectively, first and second sequences of light pulses, wherein the first optical arm includes a first manipulator configured to generate the first sequence of light pulses from the initial sequence of light pulses, wherein the light source includes a nonlinear optical element arranged to receive the first sequence of light pulses or the second sequence of light pulses, and an optical switch arranged to switch either the first sequence of light pulses or the second sequence of light pulses for reception by the nonlinear optical element.