Pixelated Array Optics for Homogeneous Surgical Laser Illumination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In ophthalmic surgeries, the illumination provided by optical fibers often results in an inhomogeneous field due to inter-mode interference, which is unsuitable for clear visualization of fine biostructures, especially with shorter and smaller diameter fibers, leading to dynamic patterns and reduced mode mixing.
Innovation Solution
The use of pixelated array optics, such as digital micromirror devices or LCD phase plates, to impart motion to the focal spot within the optical fiber, enhancing mode mixing and generating a homogeneous illumination field by controlling the movement of the focal spot based on intensity measurements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If optical fibers are used for surgical illumination, then high light intensity is provided within small physical dimensions, but the illumination field becomes inhomogeneous due to inter-mode interference
Solution Approach 1:
The patent applies dynamics by moving the focal spot across the fiber core rather than keeping it stationary. This dynamic scanning of the focal spot induces mode mixing in the optical fiber, transforming the inhomogeneous illumination field into a homogeneous one while preserving the high light intensity capability of the fiber.
Solution Approach 2:
The patent employs mechanical vibration principles by rapidly moving the focal spot across the fiber core at high frequencies. This vibration-induced mode mixing effectively homogenizes the illumination field by continuously redistributing the light modes within the fiber, eliminating the static inhomogeneous patterns.
2Length of moving object
If shorter and smaller diameter fibers are used, then the physical dimensions are reduced for better access, but mode mixing is reduced leading to worse illumination homogeneity
Solution Approach 1:
The patent compensates for the reduced mode mixing in shorter fibers by introducing dynamic focal spot scanning. This external dynamic mechanism induces sufficient mode mixing even in short fibers, achieving homogeneous illumination without requiring the fiber to be long enough to naturally mix modes.
Solution Approach 2:
The patent applies preliminary action by pre-processing the light beam before it enters the fiber by scanning the focal spot across the core. This preliminary mode mixing action ensures that the illumination field becomes homogeneous before the light propagates through the fiber, overcoming the limited mixing capacity of short fibers.
3Device complexity
If a stationary focal spot is used, then the system is simpler to control, but inter-mode interference creates dynamic patterns that reduce visualization quality
Solution Approach 1:
The patent introduces controlled dynamics by scanning the focal spot across the fiber core at high frequencies. This dynamic scanning suppresses the visible dynamic patterns caused by inter-mode interference by rapidly averaging the illumination, while the scanning motion itself is simple and can be implemented with basic piezoelectric actuators.
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 provides a stable, uniform illumination field, improving surgical visibility and enabling safer and more effective procedures by minimizing inter-mode interference and adapting to varying conditions.
Implementation Method 1
The use of pixelated array optics, such as digital micromirror devices or LCD phase plates, to impart motion to the focal spot within the optical fiber, enhancing mode mixing and generating a homogeneous illumination field
Implementation Method 2
controlling the pixelated phase array to direct the second light onto a focal spot at a fiber core of an optical fiber, the second light used for illumination of a patient during a surgery. In the method, focal spot is moved over the fiber core. The method may further include measuring an intensity of the second light from the optical fiber, and based on the intensity measured, controlling the pixelated phase array to limit movement of the focal spot to the fiber core.
Data Source
AI summary
Pixelated array optics for mode mixing may be used to homogenize different modes in an optical fiber used for surgical illumination. A pixelated phase array, such as a digital micromirror device or an LCD phase plate, may impart motion to an incident beam entering the optical fiber to generate a homogeneous illumination field from a coherent light source.