DLP Fundus Imaging With DMD-Controlled Multispectral Illumination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional fundus imaging techniques are limited by pupil size variations, misalignment issues, and the use of fixed white LEDs, which result in suboptimal image quality, harsh illumination, and limited ability to capture multiple images due to pupil constriction.
Innovation Solution
Employing a digital micromirror device (DMD) to dynamically adjust illumination patterns, including IR and multispectral light sources, to compensate for misalignment and pupil size, enabling multiple image capture before constriction and improving color balance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If fixed white LEDs are used for illumination, then the imaging system is simple, but image quality is suboptimal and color balance is poor
Solution Approach 1:
The patent changes the illumination parameters from fixed white light to variable wavelength light. The system uses multiple LEDs emitting at different wavelengths (e.g., 450nm, 530nm, 630nm) and dynamically adjusts which wavelengths are activated based on the imaging requirements, thereby optimizing image quality and color balance while maintaining system simplicity.
Solution Approach 2:
The patent introduces dynamic control of illumination patterns using a digital micromirror device (DMD) that can rapidly switch between different illumination patterns and wavelengths. This dynamic adaptation allows the system to optimize illumination for each specific imaging scenario, improving image quality without requiring a complex fixed illumination system.
2Device complexity
If conventional illumination is used, then the system is simple, but pupil misalignment causes imaging failures
Solution Approach 1:
The patent applies local quality by using the DMD to create specific illumination patterns that are precisely targeted at the pupil region. Rather than uniform illumination, the system selectively illuminates only the relevant areas, compensating for misalignment and ensuring reliable imaging even when pupil position varies.
Solution Approach 2:
The system incorporates feedback mechanisms where the DMD adjusts illumination patterns based on detected pupil position and size. This closed-loop control ensures that illumination is always properly aligned with the pupil, significantly improving imaging reliability without requiring a complex mechanical alignment system.
3Productivity
If bright white light is used for illumination, then image capture is fast, but pupil constriction prevents multiple image capture
Solution Approach 1:
The patent uses periodic action by implementing sequential illumination at different wavelengths rather than continuous bright white light. The DMD cycles through different wavelength patterns (e.g., blue, green, red LEDs sequentially), allowing multiple images to be captured during the pupil dilation period while maintaining adequate illumination for each capture.
Solution Approach 2:
The system dynamically adjusts illumination intensity and wavelength sequencing to match the pupil response characteristics. By using lower intensity, wavelength-specific illumination rather than intense white light, the system extends the usable imaging window while maintaining capture speed through rapid LED switching and synchronized DMD pattern changes.
4Device complexity
If uniform illumination is used, then the illumination system is simple, but motion artifacts occur during image capture
Solution Approach 1:
The patent segments the illumination into multiple wavelength components and spatial regions using the DMD. Instead of uniform illumination, the system divides the fundus into regions and illuminates them with appropriate wavelengths sequentially, reducing motion artifacts by shortening the effective exposure time for each region while maintaining overall image clarity.
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
Enhances image quality by avoiding non-pupil illumination, reduces motion artifacts, and allows for high-resolution imaging with gentler illumination, capturing multiple images before pupil constriction.
Implementation Method 1
a digital micromirror device (DMD) configured to project illumination patterns onto a subject's eye using the light emitted from the illumination source
Implementation Method 2
an illumination source configured to emit light of a plurality of colors including a first color
Data Source
AI summary
Some aspects relate to techniques for imaging a fundus of a subject's eye using an apparatus comprising, an illumination source, a digital micromirror device (DMD), a fundus imaging device, and a processor.