Adaptive Optics Retinal Imaging with TPEF and SHG
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current ophthalmic diagnostic equipment faces challenges in effectively imaging retinal tissues like Retina Pigment Epithelium (RPE) and Lamina Cribrosa due to optical and phase aberrations introduced by the eye, which affect the accuracy of Two Photon Excited Fluorescence (TPEF) and Second Harmonic Generation (SHG) phenomena.
Innovation Solution
A system and method utilizing a laser unit to generate ultra-short pulsed light beams that compensate for optical and phase aberrations using a sensor with adaptive optics, allowing for selective imaging of RPE or LC tissues by exploiting TPEF or SHG phenomena, with a detector receiving return light beams of different wavelengths for imaging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If adaptive optics with wavefront sensor is used to compensate for optical aberrations, then imaging precision is improved, but device complexity increases
Solution Approach 1:
The system uses a single ultra-short pulsed laser source to generate multiple wavelengths through nonlinear optical processes (TPEF and SHG) within the retina itself. This multi-functional approach allows imaging of different retinal tissues (RPE and LC) using one laser system rather than requiring separate laser sources for each imaging modality, thereby improving imaging precision while controlling device complexity
Solution Approach 2:
The system exploits changes in optical parameters (wavelength) by utilizing the different wavelength components generated through TPEF and SHG phenomena. By detecting and analyzing these wavelength-specific return beams, the system achieves high imaging precision for different tissue types while maintaining a relatively simple laser source configuration
2Measurement precision
If ultra-short pulsed laser is used to exploit TPEF and SHG phenomena, then imaging quality is improved, but cost increases
Solution Approach 1:
A single ultra-short pulsed laser source performs multiple imaging functions by generating both TPEF and SHG signals within the retina. This eliminates the need for separate laser systems for imaging different retinal tissues, thereby improving imaging quality while reducing overall system cost compared to using multiple specialized laser sources
Solution Approach 2:
The retinal tissue itself generates the different wavelength components through its intrinsic nonlinear optical properties (TPEF and SHG phenomena). The tissue acts as the nonlinear optical medium, eliminating the need for external nonlinear optical crystals or complex wavelength conversion components, thus improving imaging quality while simplifying system design and reducing cost
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 precise and cost-effective imaging of specific retinal tissues by compensating for aberrations and utilizing the appropriate wavelength components for TPEF or SHG, improving imaging quality and ease of use.
Implementation Method 1
One is known as Two Photon Excited Fluorescence (TPEF). This phenomenon is efficacious for imaging the RPE of the retina.
Implementation Method 2
The other phenomenon is Second Harmonic Generation (SHG), which is efficacious for imaging the LC.
Data Source
Figure 1~4
Figure 5
AI summary
A system and method for imaging retinal tissues in an eye generates an input light beam having ultra-short pulses and an input wavelength (λi) to stimulate the tissue. Depending on the particular type tissue being imaged, the retinal tissue responds to the input beam by generating a return beam of light having first and second components of different wavelengths (λr1 and Ar2). An imaging unit then receives the return light and images the tissue according to the return wavelength (Xr1 vis-a-vis λr2). Additionally, a sensor unit is used to evaluate light returning from the retina to measure optical and phase aberrations introduced by the eye, and to program a compensator (e.g. an active mirror) that compensates the input beam by removing the aberrations.