Optical Modulator Module Cylindrical Lens Array Beam Shaping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Semiconductor modulators face optical coupling loss due to mode mismatch when coupled with optical fibers, primarily because the elliptical shape of the light output from semiconductor waveguides does not match the circular mode field of fibers, leading to increased manufacturing complexity and cost.
Innovation Solution
The use of two cylindrical lens arrays with intersecting longitudinal directions, made from high refractive index materials like silicon, to shape the output light from semiconductor modulators into a circular beam, reducing optical coupling loss and simplifying the optical axis adjustment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If semiconductor modulators are used to reduce size, then miniaturization is achieved, but optical coupling loss increases due to mode mismatch between elliptical waveguide output and circular fiber mode field
Solution Approach 1:
A cylindrical lens array is introduced as an intermediary component between the semiconductor modulator and optical fiber. The lens array transforms the elliptical light output from the waveguides into a circular beam profile that matches the fiber's mode field distribution, thereby reducing optical coupling loss while maintaining the compact size advantage of semiconductor modulators
Solution Approach 2:
The invention changes the optical parameters of the light beam by using cylindrical lenses to transform the elliptical intensity distribution into a circular one. This parameter transformation (from elliptical to circular beam shape) enables better mode matching with the optical fiber, resolving the coupling loss issue without sacrificing miniaturization
2Loss of energy
If conventional beam shaping methods are used to match mode fields, then coupling efficiency improves, but manufacturing complexity and cost increase
Solution Approach 1:
Instead of using a single complex aspherical lens that is difficult to manufacture, the invention segments the beam shaping function into multiple cylindrical lenses arranged in an array. Each cylindrical lens has a simple cylindrical geometry that is easy to fabricate, while the collective array achieves the desired circular beam transformation, thus reducing manufacturing complexity and cost
Solution Approach 2:
The invention approaches the beam shaping problem from a different dimensional perspective by using cylindrical lenses that focus light in one dimension while leaving it unchanged in the perpendicular dimension. This dimensional decomposition simplifies the manufacturing of each individual lens while the array configuration collectively achieves the two-dimensional circular beam profile needed for optimal fiber coupling
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 configuration minimizes excess loss and diffraction, allowing for efficient coupling of light into optical fibers with reduced component complexity and cost, while maintaining high refractive index changes for effective beam collimation.
Implementation Method 1
a first cylindrical lens that has a longitudinal direction in a direction in which the plurality of output waveguides are aligned, and through which lights output from the plurality of output waveguides penetrate; and a plurality of second cylindrical lenses each having a longitudinal direction that intersects with the longitudinal direction of the first cylindrical lens
Data Source
AI summary
An optical modulator module includes: a semiconductor modulator that includes a plurality of output waveguides; a first cylindrical lens that has a longitudinal direction in a direction in which the plurality of output waveguides are aligned, and through which lights output from the plurality of output waveguides penetrate; and a plurality of second cylindrical lenses each having a longitudinal direction that intersects with the longitudinal direction of the first cylindrical lens and allowing a corresponding light of the lights output from the plurality of output waveguides to penetrate therethrough.