Cascaded DLI Multiplexer for Compact Optical Signal Routing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical multiplexers are large, have high insertion loss, and are expensive, making them unsuitable for space-constrained applications and requiring improvements in size and efficiency.
Innovation Solution
A cascaded delay line interferometer (DLI) multiplexer with multiple stages, each including 2×2 multi-mode interference devices and MMI combiners, achieving low coupling loss and a compact footprint, capable of multiplexing multiple optical signals with precise wavelength alignment and temperature stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If arrayed waveguide gratings or bulk optics MUX designs are used, then wavelength multiplexing capability is achieved, but device size becomes large
Solution Approach 1:
The MUX is divided into multiple stages, with each stage handling a subset of wavelength channels. The first stage multiplexes a first set of channels, the second stage multiplexes a second set of channels, and the third stage combines both sets. This segmentation allows each individual MUX device to be compact while the cascaded system achieves comprehensive wavelength multiplexing capability.
Solution Approach 2:
The patent transitions from single-stage planar MUX designs to a multi-stage cascaded architecture, adding the dimension of temporal/sequential processing. By distributing the multiplexing function across multiple stages connected in sequence, the system achieves high channel capacity without requiring a large single-device footprint.
2Adaptability or versatility
If arrayed waveguide gratings or bulk optics MUX designs are used, then wavelength multiplexing capability is achieved, but insertion loss increases
Solution Approach 1:
The multiplexing function is segmented across three stages, with each stage handling a manageable subset of wavelength channels. This segmentation allows each individual MUX device to operate at optimal efficiency points, minimizing insertion loss per stage. The overall system achieves low total insertion loss because each segment operates independently at high efficiency rather than attempting to handle all channels in a single lossy device.
3Adaptability or versatility
If arrayed waveguide gratings or bulk optics MUX designs are used, then wavelength multiplexing capability is achieved, but manufacturing cost increases
Solution Approach 1:
The MUX system is segmented into three separate, identical-stage devices that can be manufactured using the same standardized process. This modular segmentation enables mass production of each stage type, reducing per-unit manufacturing costs through economies of scale. The standardized design of each stage simplifies fabrication compared to custom single-stage high-channel-count MUX devices.
Solution Approach 2:
The patent uses three copies of a standardized two-wavelength MUX stage design. By replicating a proven, optimized stage design multiple times and cascading them, the system achieves high channel capacity without the need to manufacture complex single-stage high-channel devices. This copying approach leverages the cost benefits of standardized manufacturing while achieving the required multiplexing capability.
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 DLI multiplexer provides a compact, low-loss solution for multiplexing multiple optical signals with reduced size and cost, maintaining precise wavelength alignment and temperature stability, enhancing extinction ratio and reducing inter-channel cross-talk.
Implementation Method 1
delay line interferometer (DLI) multiplexer (MUX) includes a first stage and a second stage. The first stage includes a first DLI and a second DLI
Implementation Method 2
each including 2×2 multi-mode interference devices and MMI combiners
Data Source
AI summary
In an embodiment, a delay line interferometer (DLI) multiplexer (MUX) includes a first stage and a second stage. The first stage includes a first DLI and a second DLI. The first DLI includes a first left input, a first right input, and a first output and has a free spectral range (FSR) that is about four times a nominal channel spacing. The second DLI includes a second left input, a second right input, and a second output and has an FSR that is about four times the nominal channel spacing. The second stage is coupled to the first stage and includes a third DLI. The third DLI includes a third left input optically coupled to the first output, a third right input optically coupled to the second output, and a third output. An FSR of the third DLI is about two times the nominal channel spacing.