Image Waveguide Refractive Index Tuning for Travel Time Compensation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing endoscopes face challenges in achieving high spatial resolution, flexibility, and undisturbed transmission of femtosecond pulses due to travel time differences and phase distortions in optical fibers, which limit their application in minimally invasive procedures.

Innovation Solution

A method and device that utilize high-energy electromagnetic radiation to adjust the effective refractive indices of optical fibers, allowing for compensation of travel time differences and implementation of a desired travel time profile by selectively changing the refractive indices of specific fibers using ultra-short pulses and excimer light.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of moving object

If the diameter of the endoscope is reduced to enable minimally invasive procedures, then flexibility and ease of insertion are improved, but maintaining high spatial resolution and undisturbed transmission of femtosecond pulses becomes difficult due to travel time differences in optical fibers

Engineering Contradiction:

Improveendoscope diameterVSAvoidspatial resolution

Core Design Contradiction:

Length of moving objectVSManufacturing precision

Solution Approach 1:

The patent changes the refractive index parameter of selected optical fibers by exposing them to high-energy electromagnetic radiation (UV or femtosecond laser). This modifies the optical path length of individual fibers to compensate for travel time differences, enabling undisturbed transmission of femtosecond pulses even in miniaturized endoscopes with reduced diameters.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent applies local quality by selectively modifying only specific optical fibers that exhibit travel time differences greater than a threshold value. The refractive index correction is applied locally to individual fibers or subsets of fibers, while leaving other fibers unchanged, thereby maintaining high spatial resolution without requiring modification of the entire fiber bundle.

Inventive Principle:

Principle #3Local quality

2Manufacturing precision

If complex distal imaging optics are added to increase absolute spatial resolution, then imaging quality is improved, but the endoscope diameter increases to the millimeter range

Engineering Contradiction:

Improvespatial resolutionVSAvoidendoscope diameter

Core Design Contradiction:

Manufacturing precisionVSLength of moving object

Solution Approach 1:

The patent replaces mechanical imaging optics with an optical path compensation approach. Instead of using physical lenses and mirrors at the distal end to achieve high resolution, the method uses refractive index modification of optical fibers to correct travel time differences, thereby maintaining high spatial resolution without requiring bulky mechanical imaging components.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Reliability

If high-energy electromagnetic radiation is applied to change refractive indices, then travel time differences are compensated, but the endoscope structure and fiber integrity must be maintained without damage

Engineering Contradiction:

Improvetravel time compensationVSAvoidfiber damage

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent applies partial action by exposing only selected optical fibers to high-energy electromagnetic radiation, rather than the entire fiber bundle. The exposure parameters (energy, duration, wavelength) are carefully controlled to achieve the necessary refractive index change without exceeding the damage threshold of the fiber material, thereby maintaining fiber integrity while achieving travel time compensation.

Inventive Principle:

Principle #16Partial or excessive action

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 enables the compensation of travel time differences and phase distortions, facilitating high-resolution, flexible, and cost-effective imaging with reduced fiber diameters, suitable for applications like cancer diagnostics and nonlinear endomicroscopy.

Implementation Method 1

changing the effective refractive indices of optical fibers by means of high-energy electromagnetic radiation

Methodology Applied

Scientific EffectRefraction: Refraction

Implementation Method 2

UV radiation, in particular excimer light, wherein the excimer light comprises excimer light and/or excimer laser light

Methodology Applied

Scientific EffectUV radiation effect: Photo-oxidation

Data Source

PatentUS20250298265A1Method for compensating the travel time differences of image waveguides

Publication Date: 2025.09.25 TECHNISCHE UNIVERSITAT DRESDEN

AI summary

The invention relates to a method and a device for compensating for the travel time differences of image waveguides and/or for implementing a desired travel time profile, as well as to the use of the method and the device. The method involves changing the effective refractive indices of optical fibers by means of high-energy electromagnetic radiation, which are enclosed by an image waveguide. Possible applications of the method and device include, but are not limited to, cancer diagnostics, nonlinear endomicroscopy, optical coherence tomography (OCT), optical coherence tomography with tuned wavelength of the radiation source (swept source OCT), the undisturbed transmission of femtosecond pulses and/or the correction of travel time differences that occur in image waveguides that have optical fibers twisted with each other.