Interference Imaging for 3D Refractive Index Mapping in Scattering Tissue
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional optical diffraction tomography (ODT) struggles to effectively observe three-dimensional cell tissues due to the overwhelming influence of multiple scattered light, which leads to speckle generation and deterioration of the single-to-multi-scattering ratio (SMR), making it difficult to extract structural information.
Innovation Solution
An observation apparatus and method that utilize an interference intensity image acquisition unit, complex amplitude image generation units, phase image generation units, and refractive index distribution calculation to sequentially process light irradiation directions, reducing the impact of multiple scattered light and enabling three-dimensional refractive index mapping of observation objects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional optical diffraction tomography (ODT) is applied to image three-dimensional cell tissues, then three-dimensional refractive index tomography can be achieved, but multiple scattered light causes speckle generation and deterioration of single-to-multi-scattering ratio, making it difficult to extract structural information
Solution Approach 1:
The observation object is divided into multiple blocks along the light propagation path direction. By processing each block separately and sequentially, the method reduces the accumulation of multiple scattered light effects within each block, thereby improving the single-to-multi-scattering ratio and reducing speckle generation while maintaining three-dimensional refractive index measurement capability
Solution Approach 2:
The complex amplitude image is propagated to the block division position before actual block processing begins. This preliminary propagation establishes the initial conditions for each block, allowing the sequential processing to effectively manage multiple scattering effects from the start of the observation object
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
The method effectively reduces the influence of multiple scattered light, allowing for accurate three-dimensional imaging and refractive index distribution analysis of multiple scattering objects like three-dimensional cell tissues.
Implementation Method 1
imaging unit for imaging the interference intensity image at the reference position generated by interference between light irradiating an observation object along each of the plurality of light irradiation directions and passed through the observation object and reference light
Implementation Method 2
Light scattering refers to a phenomenon in which light interacts with an object to change a traveling direction of the light. In particular, when spatial non-uniformity of a refractive index in the object increases, the light interacts with the object many times in passing through the object.
Data Source
AI summary
An observation apparatus includes a light source, a mirror, a condenser lens, an objective lens, a beam splitter, an imaging unit, and an analysis unit. The analysis unit includes an interference intensity image acquisition unit, a first complex amplitude image generation unit, a second complex amplitude image generation unit, a two-dimensional phase image generation unit, a three-dimensional phase image generation unit, a refractive index distribution calculation unit, and a third complex amplitude image generation unit. The analysis unit irradiates an observation object with light along each of a plurality of light irradiation directions by changing an orientation of a reflection surface of the mirror, acquires an interference intensity image for each of the plurality of light irradiation directions from the imaging unit, and performs necessary processing based on the interference intensity images to obtain a three-dimensional refractive index distribution of the observation object.