OCT Microprobe Cylindrical Reflector Transverse Resolution

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current OCT endoscopic probes face limitations in transverse resolution due to the use of grin lenses with limited numerical aperture, especially at longer working distances, and suffer from light scattering issues through cylindrical plastic casings, leading to image deformation and reduced diagnostic accuracy in deep tissue imaging.

Innovation Solution

The design incorporates a spring tube with a single-mode fiber and a glass rod with a self-focus lens, allowing adjustable working distance and increased numerical aperture, along with a cylindrical reflector to minimize light scattering, enhancing transverse resolution and image quality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a grin lens is used in the OCT microprobe, then the device structure becomes simple and production cost is low, but the numerical aperture is limited and transverse resolution decreases, especially at longer working distances

Engineering Contradiction:
Improveproduction costVSAvoidtransverse resolution
Core Design Contradiction:
Ease of manufactureVSMeasurement precision

Solution Approach 1:

A cylindrical reflector is introduced as an intermediary component between the light source and the grin lens. This reflector redirects light to increase the effective numerical aperture of the probe without requiring a more complex lens system, thereby improving transverse resolution while maintaining the simplicity and low cost of the grin lens structure.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The numerical aperture parameter is enhanced not by changing the grin lens itself but by modifying the light path through the cylindrical reflector. This allows the system to achieve higher effective numerical aperture with the same simple lens structure, resolving the contradiction between structural simplicity and measurement precision.

Inventive Principle:
Principle #35Parameter changes

2Length of stationary object

If the working distance of the OCT microprobe is increased, then the imaging depth is improved, but the transverse resolution dramatically decreases due to the limited numerical aperture of the grin lens

Engineering Contradiction:
Improveworking distanceVSAvoidtransverse resolution
Core Design Contradiction:
Length of stationary objectVSMeasurement precision

Solution Approach 1:

The cylindrical reflector serves as a mediator that extends the effective light collection angle without requiring the lens to be closer to the tissue. This allows the probe to maintain high transverse resolution even at increased working distances, as the reflector compensates for the numerical aperture limitation that would normally worsen with distance.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

Instead of improving resolution by reducing working distance (one-dimensional adjustment), the invention uses the cylindrical reflector to add a spatial dimension to light redirection. This allows the system to achieve high numerical aperture effects at longer working distances by redirecting light paths in three-dimensional space.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Strength

If a cylindrical plastic transparent casing is used for positioning and protection of the OCT microprobe, then the probe structure is protected, but light scattering occurs and the laser circular facula becomes elliptical, leading to image deformation

Engineering Contradiction:
Improvemechanical strengthVSAvoidlight scattering
Core Design Contradiction:
StrengthVSObject-affected harmful factors

Solution Approach 1:

The cylindrical reflector is positioned within the plastic casing to act as an intermediary that corrects the light path distortion caused by the casing. By redirecting scattered light and compensating for the elliptical distortion, the reflector maintains image quality while the plastic casing continues to provide mechanical protection.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The invention acknowledges the light scattering effect of the plastic casing but uses the cylindrical reflector to convert this harmful scattering into beneficial light redirection. The reflector captures scattered light and redirects it along the correct optical path, transforming the casing's negative effect into an opportunity for light path optimization.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

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 configuration improves the transverse resolution and maintains high image quality even at longer working distances, enabling more accurate deep tissue imaging and reducing the risk of misdiagnosis in internal organs.

Implementation Method 1

the single-mode fiber is transmitting inside the spring tube

Methodology Applied
Scientific EffectOptical fiber transmission: Optical Fibre

Implementation Method 2

a lens assembly making the light from the optical fiber gathering outside the preset working distance, comprises a glass rod and a self-focus lens

Methodology Applied
Scientific EffectLight focusing: Lens

Implementation Method 3

a cylindrical reflector to minimize light scattering

Methodology Applied
Scientific EffectLight reflection: Reflection

Data Source

PatentEP3295988B1Endoscopic oct microprobe, oct imaging system, and use method
Publication Date: 2021.02.24 MICRO-TECH (NANJING) CO LTD
  • EP3295988B1 patent drawingFigure 1
  • EP3295988B1 patent drawingFigure 2A
  • EP3295988B1 patent drawingFigure 2B

AI summary

An OCT microprobe applied to endoscopic high-resolution optical coherence tomography, an imaging system, and a use method, which relate to the technical field of medical instruments. By using a lens assembly, the OCT microprobe changes a working distance of the OCT microprobe, and increases a light aperture of a grin lens (4), thereby improving a numerical aperture and horizontal resolution of the OCT microprobe. The present invention can resolve a problem that in an existing OCT system, an OCT microprobe has low horizontal resolution and an image obtained through scanning changes easily. Therefore, OCT endoscopic scanning imaging with the OCT microprobe is applicable to blood vessels, digestive tracts, respiratory tracts or narrow space of human tissue.