Optical Subsampling for Extended OCT Depth Range

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional Fourier-Domain OCT systems face challenges in efficiently acquiring and processing large depth range imaging data, leading to high data volume requirements for analog-to-digital converters, cameras, and data transfer/storage, which is inefficient and resource-intensive.

Innovation Solution

The implementation of optical subsampling in FD-OCT systems to reduce data acquisition volume by characterizing scatter locations within a large delay window using a wavelength-stepped source and interferometric arrangements, allowing for reduced ADC rates, lower pixel count cameras, and lower bandwidth data buses, while maintaining high resolution in depth profiling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of stationary object

If high resolution sampling in wavenumber-space is used to detect reflections over large time delay windows, then depth range imaging capability is improved, but data volume and resource requirements increase significantly

Engineering Contradiction:
Improvedepth rangeVSAvoiddata volume
Core Design Contradiction:
Length of stationary objectVSQuantity of substance

Solution Approach 1:

The patent divides the large depth range into multiple smaller depth windows, each processed separately with appropriate sampling. By segmenting the overall imaging range, the system can use lower sampling rates for each segment while maintaining adequate resolution, thereby reducing total data volume compared to uniformly high-resolution sampling across the entire range.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces a temporal dimension by processing different depth windows at different time points. Instead of capturing all depth information simultaneously at high resolution, the system sequentially processes depth segments, effectively trading temporal resolution for reduced spatial sampling requirements in each frame, thus reducing overall data volume.

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

2Measurement precision

If high pixel count cameras or fast ADCs are used to sample interference signal at high resolution, then measurement precision is improved, but device complexity and cost increase

Engineering Contradiction:
Improvesampling resolutionVSAvoidADC rate
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent applies different sampling resolutions to different depth regions. By recognizing that not all depth ranges require the same level of detail, the system uses higher sampling resolution only where necessary (e.g., regions with expected scatterers) and lower resolution in other regions, thereby maintaining measurement precision where needed while reducing overall device complexity.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent dynamically adjusts sampling parameters (such as ADC rate or camera pixel utilization) based on the imaging requirements of different depth windows. By changing sampling parameters adaptively rather than using fixed high-resolution sampling throughout, the system maintains adequate measurement precision while significantly reducing the required ADC rate and device complexity.

Inventive Principle:
Principle #35Parameter changes

3Productivity

If large bandwidth data transfer buses and storage units are used to handle increased data volume, then productivity is improved, but loss of energy increases

Engineering Contradiction:
Improvedata processing capabilityVSAvoidenergy consumption
Core Design Contradiction:
ProductivityVSLoss of energy

Solution Approach 1:

The patent extracts and processes only the essential information from the interference signal by focusing on specific depth windows and scattering events. By filtering out redundant data and processing only relevant portions of the signal, the system reduces the bandwidth required for data transfer and storage, thereby improving productivity without requiring excessively large data buses while simultaneously reducing energy consumption.

Inventive Principle:
Principle #2Taking out (Extraction)

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 efficient data acquisition and processing, allowing for imaging over a large depth range with significantly reduced data volume, thereby improving imaging efficiency and reducing resource requirements without compromising resolution or information content.

Implementation Method 1

The sample beam can be directed at a sample to be imaged, and the reflected light from the sample is recombined with light from the reference beam (i.e., returning from the reference arm), resulting in an interference signal

Methodology Applied
Scientific EffectInterference: Interference

Implementation Method 2

the interference signal as a function of wavelength can be obtained by using a broadband light source and a spectrally dispersing unit or a spectrometer that spatially separates the recombined sample and reference light according to wavelength

Methodology Applied
Scientific EffectDispersion: Dispersion (of waves)

Data Source

PatentEP3330696B1Systems, apparatus and methods for extending imaging depth range of optical coherence tomography through optical sub-sampling
Publication Date: 2023.07.12 THE GENERAL HOSPITAL CORP
  • EP3330696B1 patent drawingFigure 1
  • EP3330696B1 patent drawingFigure 2
  • EP3330696B1 patent drawingFigure 3

AI summary

Exemplary embodiments of systems and methods can be provided which can generate data associated with at least one sample. For example, using at least one first arrangement, it is possible to forward at least one first radiation to the sample(s) so as to cause at least one second radiation to be provided from the sample(s) that can be based on the first radiation(s). In addition, using at least one second arrangement, it is possible to receive the second radiation from the sample(s), generate a plurality of distinct measurements regarding at least one portion of the sample(s) based the second radiation(s), and characterize the portion(s) over a plurality of continuous resolvable depth points thereof which are associated with the distinct measurements. Further, the characterization of the at least one portion can be resolved and distinctly characterized at a number of the depth points which is greater than a number of the distinct measurements.