Optical Device Substrate Hole Depth and Splitting Ratio
Solution Overview
Problem
Existing mosaic type optical devices with holes on the substrate surface face challenges in minimizing light loss while maintaining the desired splitting ratio.
Innovation Solution
The optical device features a substrate with a first region having a silicon layer with a plurality of holes, where the depth of each hole is half or less of the silicon layer's thickness, and a second region without the silicon layer, optimizing light confinement and scattering.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If holes are provided in the substrate surface for light splitting, then the splitting ratio can be controlled, but light loss increases
Solution Approach 1:
The substrate is divided into a first region with holes for light splitting and a second region without holes for light confinement. This local differentiation allows the device to achieve both precise splitting ratio control in the first region and reduced light loss in the second region, resolving the contradiction between splitting precision and light loss.
Solution Approach 2:
The substrate surface is segmented into functionally distinct regions: a first region containing holes for wavelength-dependent light splitting and a second region without holes for confining light within the waveguide. This segmentation enables simultaneous optimization of both splitting ratio control and light loss reduction.
2Measurement precision
If holes are made deeper to improve splitting control, then splitting precision improves, but light loss increases
Solution Approach 1:
By creating a spatial distinction between the first region (with holes for splitting) and the second region (without holes for confinement), the invention allows optimized hole depths in the first region for precise splitting while the second region prevents light loss, thereby resolving the contradiction between splitting precision and light loss.
3Ease of manufacture
If the substrate has uniform structure across the surface, then manufacturing is simplified, but light confinement and splitting cannot be simultaneously optimized
Solution Approach 1:
The substrate employs local quality differentiation with a first region containing holes for light splitting and a second region without holes for light confinement. This localized structural variation optimizes both light confinement and splitting performance simultaneously, while the overall two-layer architecture remains manufacturable using standard semiconductor fabrication processes.
Solution Approach 2:
The substrate is segmented into functionally distinct first and second regions with different structural characteristics. This segmentation enables simultaneous optimization of light confinement (in the second region) and light splitting (in the first region), resolving the contradiction between manufacturing simplicity and performance optimization.
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 effectively suppresses light loss and allows for precise control of the splitting ratio by adjusting the depth and arrangement of the holes, enhancing the device's performance.
Implementation Method 1
a first region (30) and a second region (32) in a surface (101) of the substrate 10, a first waveguide (20) configured to input light, and at least one second waveguide (22, 24) configured to output light
Data Source
AI summary
An optical device includes a substrate having a first region and a second region in a surface thereof, a first waveguide for inputting light, and at least one second waveguide for outputting light. The second region surrounds the first region. The first waveguide and the second waveguide are optically coupled to the first region. The substrate includes a first layer and a second layer sequentially stacked one on top of the other in the first region. The second layer has a plurality of holes. A depth of each of the holes is half of a thickness of the second layer or smaller. The substrate does not have the second layer and has the first layer in the second region.