Tilted Planar Waveguides for Reflective Modulator Coupling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Reflective optical modulators face challenges in optical coupling with low loss due to the use of lenses and optical circulators, leading to increased costs and complexity in optical communication systems.
Innovation Solution
An optical apparatus comprising a reflective optical modulator integrated with a planar lightwave circuit, where input and output planar waveguides are tilted and optically coupled to optical fibers, eliminating the need for optical circulators and focusing optics, and utilizing a cyclic arrayed waveguide grating for wavelength division multiplexing and demultiplexing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If lenses and optical circulators are used to couple optical signals with reflective modulators, then optical coupling can be achieved, but the device size increases and cost increases
Solution Approach 1:
The patent removes the optical circulator from the traditional coupling system by using a directional coupler structure where input and output waveguides are spatially separated and tilted towards each other. This extraction of the circulator function eliminates the need for bulky optical components while maintaining coupling efficiency.
Solution Approach 2:
The patent combines the functions of optical coupling and signal direction into a single integrated planar waveguide structure. The tilted end segments of input and output waveguides directly guide light to and from the modulator without requiring separate lenses and circulators, merging multiple functions into one compact structure.
2Reliability
If lenses and optical circulators are used to couple optical signals with reflective modulators, then optical coupling can be achieved, but the manufacturing cost increases
Solution Approach 1:
By removing the optical circulator and focusing lenses from the system, the patent eliminates expensive discrete optical components. The integrated planar waveguide structure uses standard semiconductor fabrication processes, significantly reducing manufacturing costs while maintaining coupling efficiency.
Solution Approach 2:
The patent replaces expensive, precision-aligned optical components (lenses and circulators) with a planar waveguide structure that can be manufactured using cost-effective semiconductor processing techniques, making the system more economically viable.
3Reliability
If fiber mode is imaged to the modulator using gradient-index lens or pair of lenses, then optical coupling is achieved, but the system becomes bulky and expensive
Solution Approach 1:
The patent removes the gradient-index lens or pair of lenses from the optical coupling path. Instead, the tilted end segments of the planar waveguides directly interface with the modulator, eliminating the need for bulky focusing optics and reducing overall system volume.
Solution Approach 2:
The patent transitions from using bulky three-dimensional optical components (lenses) to a planar two-dimensional waveguide structure. The tilted end segments provide the necessary optical directionality within the planar domain, eliminating the need for volumetric focusing elements.
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 provides efficient optical coupling with reduced size and cost, enhancing the simplicity and effectiveness of optical communication systems by eliminating the need for bulky and expensive circulators and focusing optics.
Implementation Method 1
reflective optical modulator configured to data modulate the optical signal and transmit said data modulated optical signal to the end segment of the output planar waveguide
Implementation Method 2
input planar waveguide is optically coupleable to a first optical fiber and the output optical waveguide is optically coupleable to a second optical fiber
Implementation Method 3
cyclic arrayed waveguide grating configured to separate the wavelength division multiplexed optical signal into demultiplexed wavelength channel optical signals
Implementation Method 4
cyclic arrayed waveguide grating wherein each of the input planar waveguides is optically coupled to a free space region of the cyclic arrayed waveguide grating
Data Source
AI summary
An optical apparatus comprising a reflective optical modulator and an integrated planar lightwave circuit. The circuit can have one or more pairs of input and output planar waveguides thereon. The input planar waveguide is optically coupleable to a first optical fiber and the output optical waveguide is optically coupleable to a second optical fiber. End segments of the input planar waveguide and the output planar waveguide are tilted towards each other such that the input planar waveguide is able to direct an optical signal from the planar lightwave circuit to a reflective modulator. The reflective optical modulator is configured to data modulate the optical signal and transmit said data modulated optical signal to the end segment of the output planar waveguide.