Ophthalmic Tomographic Image Distortion Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional OCT techniques face challenges in accurately correcting distortion in tomographic images of the eye, especially when the angle of view is large, due to varying axial lengths of different eyes, which requires calculating correction amounts for all scanning pixels in advance.
Innovation Solution
An ophthalmologic apparatus with an optical scanner, interference optical system, intraocular distance calculator, and image correcting unit that forms and corrects tomographic images based on intraocular distances, allowing for accurate distortion correction even at wide angles of view by adjusting the scanning angle and depth ranges.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional scanning correction methods are used, then the device complexity is reduced, but the manufacturing precision of tomographic image correction deteriorates when the angle of view is large
Solution Approach 1:
The patent applies preliminary action by pre-calculating and storing correction amounts for various scanning angles and axial lengths in a correction amount storage unit. Instead of performing complex real-time calculations during imaging, the system retrieves pre-computed correction data based on the measured axial length and current scanning angle, significantly simplifying the correction process while maintaining high accuracy for wide-angle tomographic images
Solution Approach 2:
The system implements self-service by automatically measuring the axial length of the subject's eye and selecting the appropriate correction amounts from the storage unit based on this measurement. The correction process is fully automated, requiring no manual intervention or complex real-time computation, as the system serves itself by retrieving the appropriate correction parameters based on the subject's specific anatomical characteristics
2Area of stationary object
If the angle of view is widened to capture more eye structures, then the area of observation is improved, but the manufacturing precision of distortion correction deteriorates due to varying axial lengths
Solution Approach 1:
The patent applies local quality by providing customized correction amounts for different scanning angles and axial lengths. Instead of using a single universal correction method, the system stores and applies specific correction parameters tailored to each combination of scanning angle and axial length, ensuring high correction accuracy across the entire wide observation area while accounting for individual variations in eye anatomy
Solution Approach 2:
The system implements parameter changes by varying the correction amounts based on the measured axial length and scanning angle. The correction amount storage unit contains multiple sets of correction parameters that are selected and applied according to the specific axial length of the subject's eye and the current scanning angle, enabling accurate distortion correction across wide observation areas with varying optical path lengths
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 high-accuracy correction of eye tomographic images across various eyeball optical systems, improving image quality and reliability by dynamically adjusting for intraocular distances and aberrations.
Implementation Method 1
an interference optical system configured to split light from a light source into reference light and measurement light, to project the measurement light onto the subject's eye via the optical scanner, and to detect interference light between returning light of the measurement light from the subject's eye and the reference light
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
This ophthalmic device comprises an optical scanner, an interference optical system, an image generation unit, an intraocular distance calculation unit, an image correction unit, and a control unit. The optical scanner is disposed at a position optically conjugate with a first site of an eye being examined. The interference optical system divides light from a light source into reference light and measurement light, irradiates the eye being examined with the measurement light through the optical scanner, and detects interference light between return light of the measurement light from the eye being examined and the reference light through the optical scanner. The image generation unit generates a tomographic image of the eye being examined which corresponds to a first moving direction of the measurement light deflected by the optical scanner on the basis of the result of detection of the interference light. The intraocular distance calculation unit determines the intraocular distance between predetermined sites of the eye being examined on the basis of the result of detection of the interference light. The image correction unit corrects the tomographic image on the basis of the intraocular distance. The control unit controls at least the optical scanner.