Wavefront Correction Using Interference Beam Scanning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Optical beams passing through random scattering media, such as biological tissue, experience distortions that blur images due to wavefront distortions, which existing adaptive optics systems struggle to correct efficiently, especially in biological tissues with severe refractive index variations.
Innovation Solution
A method and apparatus that combine two light beams with a difference frequency to create an interference beam, scan one beam transversely to determine phase and amplitude information, and apply a spatial phase compensation profile to the other beam to correct wavefront distortions without a wavefront sensor, enabling sharper imaging through random scattering media.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional adaptive optics with wavefront sensor and deformable mirror is used, then wavefront distortion can be compensated, but the system complexity and correction speed are insufficient for severe refractive index variations in biological tissue
Solution Approach 1:
The patent removes the wavefront sensor from the system, extracting only the essential function of wavefront measurement by using the detected light field information directly from the scattering medium to compute the compensation profile, thereby simplifying the device while maintaining correction effectiveness
Solution Approach 2:
The patent replaces the mechanical deformable mirror system with a computational approach that calculates the spatial phase compensation profile and applies it through optical phase modulation, substituting mechanical adjustment with optical field control for faster operation
2Productivity
If traditional adaptive optics system is used, then wavefront distortion can be corrected, but the correction speed is too slow to achieve a million degrees of freedom in under one millisecond
Solution Approach 1:
The patent performs preliminary scanning of the first light beam across multiple distinct modes in the spatial frequency domain to collect phase and amplitude information before applying the compensation profile to the second light beam, enabling rapid sequential correction without real-time mechanical adjustment
Solution Approach 2:
The patent uses periodic scanning of the first light beam through a set of N distinct modes to systematically gather wavefront information, transforming the measurement into a periodic sampling process that can be computationally processed at high speed
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 allows for rapid wavefront correction in biological tissues, achieving a million degrees of freedom in under one millisecond, three orders of magnitude faster than previous systems, and effectively focuses light beams through random scattering media, producing clear images.
Implementation Method 1
combining a first light beam and a second light beam that are separated from each other by a difference frequency into an interference beam
Implementation Method 2
directing the interference beam onto a random scattering medium; detecting measurement light from the random scattering medium
Implementation Method 3
determining a spatial phase compensation profile to apply to the second light beam; applying the spatial phase compensation profile to the second light beam
Data Source
AI summary
An apparatus includes a transverse scanning optical system in the path of a first light beam traveling along a first optic axis; a wavefront correction system in the path of a second light beam traveling along a second optic axis, the wavefront correction system including a wavefront correction device having a spatial phase profile on its surface; a beam combiner that receives the first light beam and the second light beam and outputs an interference beam having a beat frequency equal to a difference frequency between the first light beam and second light beam; and a detection system placed relative to a random scattering medium, which is in the path of the interference beam. The detection system detects measurement light produced by the random scattering medium while the interference beam strikes the random scattering medium.