Buffy Coat Imaging with Oblique Illumination

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Manual extraction of blood sample component layers after centrifugation is time-consuming, expensive, and requires significant skill due to difficulty in distinguishing layer boundaries, especially for the thin buffy coat layer, and is hindered by reflections that complicate image analysis.

Innovation Solution

An automated blood sample processor with a liquid level height sensor and optical imaging system using a camera and algorithms to determine the precise location of component layers, employing a specific illumination source with wavelengths less than 570 nm to maximize contrast and differentiate the buffy coat layer from other layers, allowing for automated collection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If manual extraction of blood sample component layers is performed, then the operator can collect the layers, but the process becomes time-consuming and requires considerable skill due to difficulty in distinguishing layer boundaries

Engineering Contradiction:
Improveextraction speedVSAvoidskill requirement
Core Design Contradiction:
ProductivityVSEase of operation

Solution Approach 1:

The patent replaces manual mechanical extraction with an automated system that uses optical imaging and image processing algorithms to detect layer boundaries and control the extraction process. The automated pipette system executes extraction based on digitally determined boundary locations, eliminating the need for manual skill in boundary detection and extraction execution.

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

Solution Approach 2:

The patent creates a digital representation (image) of the physical blood sample layers and processes this copy to determine boundary locations. The optical imaging system captures the layer structure, and algorithms analyze the image data to identify boundaries, replacing direct visual inspection with digital image analysis.

Inventive Principle:
Principle #26Copying

2Illumination intensity

If common illumination is used for imaging the blood sample, then the sample can be visualized, but reflections interfere with the image requiring complex hardware or software filtering

Engineering Contradiction:
Improveimage contrastVSAvoidfiltering complexity
Core Design Contradiction:
Illumination intensityVSDevice complexity

Solution Approach 1:

The patent changes the illumination parameters by using oblique illumination at a specific angle rather than direct perpendicular lighting. This angular parameter change reduces specular reflections from the liquid surfaces while maintaining sufficient illumination for image capture, improving contrast without requiring complex filtering systems.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent converts the harmful effect of reflections into a beneficial imaging condition by using oblique illumination. The angle of illumination is specifically chosen to minimize reflection interference while maximizing the visibility of layer boundaries, turning a potential problem into an advantage for boundary detection.

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

3Manufacturing precision

If the buffy coat layer is the fraction of interest, then specific components can be extracted, but the layer is typically relatively thin making it difficult to distinguish boundaries

Engineering Contradiction:
Improvelayer extraction precisionVSAvoidboundary detection difficulty
Core Design Contradiction:
Manufacturing precisionVSDifficulty of detecting and measuring

Solution Approach 1:

The patent replaces manual visual boundary detection with automated optical imaging and image processing. The system captures images of the blood sample layers and uses algorithms to automatically identify boundary locations, providing precise measurement of the thin buffy coat layer that would be difficult to detect visually.

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

Solution Approach 2:

The patent introduces an intermediary optical imaging system between the blood sample and the detection process. The imaging system captures optical information from the layers, and image processing algorithms analyze this intermediate representation to precisely locate boundaries, enabling accurate detection of the thin buffy coat layer.

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 accurate and efficient detection and collection of discrete component layers, particularly the buffy coat layer, reducing manual effort and error, and improving image analysis by minimizing reflection interference.

Implementation Method 1

Commonly, reflections interfere with the image and require complex hardware or software filtering

Methodology Applied
Scientific EffectReflection: Reflection

Implementation Method 2

using a camera to image the container with the centrifuged blood sample therein

Methodology Applied
Scientific EffectScattering: Scattering

Implementation Method 3

Blood samples are often analyzed or processed by centrifuging the blood sample to separate out particular components of the blood sample into component layers

Methodology Applied
Scientific EffectCentrifugal separation: Centrifugal Separation

Data Source

PatentEP3877747B1Method and apparatus for buffy coat imaging
Publication Date: 2024.11.20 REVVITY HEALTH SCIENCES INC
  • EP3877747B1 patent drawingFigure 1
  • EP3877747B1 patent drawingFigure 2
  • EP3877747B1 patent drawingFigure 3

AI summary

A blood sample processor for imaging a centrifuged blood sample is provided including a transparent container with the centrifuged blood sample therein. An illumination source is position to illuminate the centrifuged blood sample at a non-right angle to the transparent container. A digital camera disposed opposite the transparent container images the centrifuged blood sample and the image is processed to determine the relative locations of component layers of the centrifuged blood sample.