Rotating Diffraction Grating Fundus Camera for Photoreceptor Imaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current ophthalmological imaging techniques, such as fundus cameras and confocal scanning laser ophthalmoscopy, are not capable of achieving sufficient resolution to visualize photoreceptors in the human eye due to limited optical resolution and depth of focus, making it difficult to diagnose and treat diseases at an early stage.
Innovation Solution
A modified fundus camera system incorporating a rotatable periodic optical grid synchronized with flash illumination, allowing for rapid sequence imaging and processing to enhance resolution and depth contrast, producing high-contrast images comparable to confocal techniques.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional fundus camera or confocal scanning laser ophthalmoscopy is used, then the examination of the fundus can be performed, but the resolution is insufficient to visualize photoreceptors
Solution Approach 1:
The patent segments the imaging process into multiple sequential steps: capturing multiple images at different focal depths, then computationally combining them. This allows achieving high resolution photoreceptor visualization without requiring a single complex optical system,而是 using standard fundus camera with computational processing
Solution Approach 2:
The patent extends the imaging from two-dimensional surface imaging to three-dimensional volumetric imaging by capturing images at multiple focal depths (different z-positions). This additional depth dimension enables resolution of photoreceptors that lie beneath the retinal surface, overcoming the limitation of conventional 2D fundus photography
2Measurement precision
If higher magnification is used to improve resolution, then photoreceptor details can be seen, but the depth of focus decreases making it difficult to capture entire photoreceptor structures
Solution Approach 1:
The patent performs preliminary action by capturing multiple images at different focal depths before final image processing. This pre-capture of depth information allows subsequent computational combination to achieve both high lateral resolution and adequate depth of focus in the final composite image
Solution Approach 2:
The system performs periodic action by systematically varying the focus position through a sequence of discrete depth steps, capturing images at each position. This periodic focal variation enables comprehensive sampling of the photoreceptor structure through its depth, which is then reconstructed into a complete high-resolution image
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 the generation of high-contrast, high-resolution images of photoreceptors in vivo, overcoming the limitations of existing fundus cameras by improving lateral and axial resolution, facilitating early disease detection and treatment.
Implementation Method 1
in a plane conjugate to the object plane, there is an optical grid that can be rotated into different positions
Implementation Method 2
The interference of the signals (optical cross-correlation) from both arms results in an interference pattern
Implementation Method 3
at least one illumination unit for realizing continuous and flash illumination
Data Source
Figure 1
AI summary
The invention relates to a solution which allows, in addition to the conventional examinations of the eye fundus, also the photoreceptors to be imaged and/or examined. The device for examining the eye fundus consists of an illumination beam path (3) in which, in addition to optical beam forming and/or guiding components (4), at least one illumination unit for providing a continuous illumination (5) and a flash illumination (6), and an observation and imaging beam path (7) which, in addition to optical beam forming and/or guiding components (4) and a device for varying the magnification (8), comprises a beam splitter (9) for splitting the observation and imaging beam path (7). A rotatable diffraction grating (12) is disposed in a plane in the observation and imaging beam path (7) that is conjugated with respect to the object plane and the movement of said grating is synchronized with the illumination unit that serves as the flash illumination (6) so that an image recording sensor (11) is enabled to record a rapid sequence of images of the eye fundus at different positions of the grating (12) and said sequence is forwarded to an existing evaluation unit.