Semiconductor Optical Amplifier Curved Waveguide Coupling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor optical amplifiers with distributed-Bragg-reflector waveguides face limitations in improving optical coupling efficiency, as parameters such as wavelength and angle of incidence are not adjustable for enhanced performance.
Innovation Solution
A semiconductor optical amplifier design featuring a conductive region with a continuously reduced width between the light-coupling and light-amplifying portions, utilizing a connecting region with arc-shaped outline segments to enhance optical coupling efficiency by reducing reflection losses and improving light guidance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a conventional distributed-Bragg-reflector waveguide structure is used, then the amplifier structure is simple and easy to manufacture, but the optical coupling efficiency is limited and cannot be improved by adjusting parameters
Solution Approach 1:
The patent applies curvature by introducing arc-shaped outline segments in the connecting portion between the light-coupling and light-amplifying portions. Specifically, the conductive region has a first curvature radius R1 in the light-coupling portion, a second curvature radius R2 in the light-amplifying portion, and utilizes curved transition paths with controlled curvature radii (5μm≤R1≤20μm, 10μm≤R2≤30μm) to reduce light reflection and improve coupling efficiency from -10dB to -7.2dB or higher.
Solution Approach 2:
The patent applies local quality by creating different structural characteristics in different regions of the waveguide. The light-coupling portion has a wider conductive region with curvature radius R1, the light-amplifying portion has a narrower conductive region with curvature radius R2, and the connecting portion has a gradual transition with controlled curvature. This localized variation in geometry optimizes light coupling at the input while maintaining amplification performance in the active region.
2Loss of energy
If the width of the conductive region is continuously reduced from the light-coupling portion to the light-amplifying portion, then optical coupling efficiency is improved, but the manufacturing precision requirements increase
Solution Approach 1:
The patent applies parameter changes by optimizing the curvature radii parameters R1 and R2 within specific ranges (5μm≤R1≤20μm, 10μm≤R2≤30μm) to achieve the best balance between optical coupling efficiency and manufacturing feasibility. The gradual width transition with controlled curvature parameters reduces light reflection losses while maintaining manufacturability through defined geometric constraints.
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
The design achieves improved optical coupling efficiency, with specific curvature radii ranges demonstrating enhanced performance, specifically achieving an optical coupling efficiency of −7.2 dB or higher, effectively guiding light from an external source into the amplifier.
Implementation Method 1
a conductive region that is provided on a substrate and allows light transmission
Implementation Method 2
a portion where a width of the conductive region is continuously reduced from the first region to the second region... optical coupling efficiency is higher than in a configuration not including a portion where the width of the conductive region is continuously reduced
Implementation Method 3
a second region having a narrower width than the first region and connected to the first region through a connecting portion, the second region including a light-amplifying portion amplifying the light from the light-coupling portion by propagating the light in a predetermined propagating direction along a surface of the substrate
Data Source
AI summary
A semiconductor optical amplifier includes a conductive region that is provided on a substrate and allows light transmission, and a nonconductive region that is provided around the conductive region and prohibits light transmission. The conductive region includes a first region including a light-coupling portion to which light from an external light-source unit is coupled, and a second region having a narrower width than the first region and connected to the first region through a connecting portion, the second region including a light-amplifying portion amplifying the light from the light-coupling portion by propagating the light in a predetermined propagating direction along a surface of the substrate, the light-amplifying portion outputting the amplified light in a direction intersecting the surface of the substrate. Seen in a direction perpendicular to the surface of the substrate, the semiconductor optical amplifier includes a portion where a width of the conductive region is continuously reduced from the first region to the second region.