Digital Holography Defocused Imaging for Cell Feature Resolution

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Digital holography imaging systems face challenges in resolving the internal structure of cells due to insufficient resolution with a planar incident wave setup, making cell differential analysis difficult, especially in lens-free configurations used in lab-on-chip systems.

Innovation Solution

A method and system that direct a wavefront of coherent radiation through a sample, capture interference patterns, numerically reconstruct defocused images with a predetermined offset from the focal plane, and calculate features from these images, enhancing resolution and tolerance to depth errors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a planar incident wave setup is used in digital holography imaging, then the system is simple and compact, but the resolution is insufficient to resolve the internal structure of cells

Engineering Contradiction:
Improvesystem simplicityVSAvoidresolution
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent transitions from 2D shadow imaging to 3D holographic reconstruction by capturing interference patterns that encode depth information. The numerical reconstruction process reconstructs images at different focal planes, adding the depth dimension to resolve internal cell structures while maintaining a compact lens-free setup.

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

Solution Approach 2:

The patent changes the imaging parameter from direct shadow capture to interference pattern capture, and further to reconstructed images at different focal planes. By varying the focal plane position during reconstruction, the system achieves high resolution for internal structures while maintaining system simplicity.

Inventive Principle:
Principle #35Parameter changes

2Loss of information

If a traditional lens system is used to obtain focused images, then more information is available, but the system becomes more expensive and sensitive to vibrations

Engineering Contradiction:
Improveinformation qualityVSAvoidsystem cost and sensitivity
Core Design Contradiction:
Loss of informationVSDevice complexity

Solution Approach 1:

The patent extracts the imaging function from the physical lens and implements it numerically through computer algorithms. The lensless setup captures interference patterns that contain all necessary information, and the numerical reconstruction process replaces the optical focusing function, eliminating expensive and vibration-sensitive lens components.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent replaces the mechanical/optical lens system with a computational approach. Instead of using physical lenses to focus light, the system uses numerical algorithms to reconstruct focused images from interference patterns, substituting mechanical/optical components with computational processing.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Device complexity

If lens-free imaging without holographic reconstruction is used, then the setup is simplified, but the image quality is low

Engineering Contradiction:
Improvesetup simplicityVSAvoidimage quality
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent performs preliminary capture of interference patterns that encode complete 3D information about the sample. Although the raw pattern doesn't show an apparent image, it contains all holographic information needed for high-quality reconstruction, enabling later numerical processing to achieve high image quality while maintaining simple setup.

Inventive Principle:
Principle #10Preliminary 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 provides a cost-effective and high-resolution method for determining features of objects in suspensions, such as cells, by utilizing defocused imaging to increase pixel coverage and simplify feature extraction, enabling accurate classification and differentiation of cell types.

Implementation Method 1

Light is diffracted by the illuminated object or substance and interferes with the reference light from the illumination source

Methodology Applied
Scientific EffectDiffraction: Diffraction

Implementation Method 2

capturing a pattern of interference between the wavefront of coherent radiation and a wavefront diffracted by the objects

Methodology Applied
Scientific EffectInterference: Interference

Data Source

PatentEP3339835B1Method and system for determining features of objects in a suspension
Publication Date: 2021.09.22 MIDIAGNOSTICS NV
  • EP3339835B1 patent drawingFigure 1a
  • EP3339835B1 patent drawingFigure 1b~2b
  • EP3339835B1 patent drawingFigure 3a~3c

AI summary

A method of directing a wavefront of coherent radiation through a sample of objects in a suspension, capturing an interference pattern between the wavefront of coherent radiation and a wavefront of the diffracted by the object with an image sensor, numerically determining the focal plane of at least one object, and numerically reconstructing a de-focused image of the at least one object from the interference pattern in an image plane which is substantially parallel to the image sensor and in a plane with a predetermined offset from the focal plane. The method further includes identifying at least one portion in the defocused image corresponding to the at least one object in the sample, and calculating from each of said portions at least one feature of the corresponding object.