Integrated Photonic Devices for Bidirectional Fiber Coupling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical systems face challenges in achieving cost-effective bidirectional functionality using discrete photonic devices, particularly in applications like Passive Optical Networks (PON) and high-definition DVDs, due to fabrication difficulties and high costs associated with multiple photonic devices accessing a single optical fiber.
Innovation Solution
Monolithically integrated solid-state light receiving and emitting photonic devices are fabricated on a common substrate using multilayer epitaxy, allowing for the integration of lasers and detectors on separate mesas to optimize bidirectional coupling with a single optical fiber, with each device emitting or receiving light at distinct wavelengths.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple discrete photonic devices are used to achieve bidirectional functionality, then the functional capability is improved, but the fabrication complexity and cost increase significantly
Solution Approach 1:
The patent combines multiple discrete photonic devices (lasers and detectors) onto a single integrated photonic chip, merging their functions into one unified device. This integration allows bidirectional photonic operation while eliminating the fabrication complexities associated with assembling and aligning multiple separate devices, directly resolving the technical contradiction between functional capability and fabrication complexity.
Solution Approach 2:
The integrated photonic chip is designed to perform multiple functions simultaneously - it can both transmit and receive optical signals bidirectionally, and support multiple wavelengths. This multi-functional design achieves adaptability without requiring separate specialized devices, thereby reducing fabrication complexity while maintaining versatile functionality.
2Adaptability or versatility
If multiple discrete photonic devices are used for bidirectional operation, then the functional capability is improved, but the manufacturing cost increases
Solution Approach 1:
By merging multiple photonic devices into a single integrated chip, the patent reduces the total number of components that need to be manufactured, assembled, and tested. This consolidation significantly lowers manufacturing costs while maintaining the bidirectional operational capability, directly addressing the contradiction between functional capability and manufacturing cost.
Solution Approach 2:
The patent utilizes wavelength division multiplexing, changing the optical parameter of wavelength to enable bidirectional communication over a single fiber. Different wavelengths are used for transmitting and receiving signals, allowing the system to achieve dual functionality without requiring separate physical paths, thereby reducing manufacturing complexity and cost.
3Productivity
If multiple photonic devices are integrated on a single chip, then the coupling efficiency to a single fiber is improved, but the fabrication precision requirements increase
Solution Approach 1:
The patent employs multilayer epitaxial growth to create vertically stacked photonic structures on the chip. By utilizing the vertical dimension through multiple layers, the design achieves efficient optical coupling to the fiber while distributing the fabrication precision requirements across different layers and planes, making the high-precision fabrication more manageable through standardized layer-by-layer manufacturing processes.
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 approach enables efficient and cost-effective bidirectional photonic operation by integrating multiple emitters and detectors on a single chip, facilitating high-efficiency coupling with a single optical fiber, thereby reducing costs and enhancing functionality in optical systems.
Implementation Method 1
A metal layer on the surface of the laser provides an electrical contact for application of a suitable bias voltage to cause the laser structure to produce laser light of a known wavelength
Implementation Method 2
Transform Electrical Energy to Optical Energy
Implementation Method 3
directing a beam of light upwardly through an external lens to an external optical device such as a single optical fiber
Implementation Method 4
The fiber also may direct light of a second wavelength toward the chip, with this received light passing through the lens. Since the received light is of a different wavelength than the light emitted by the laser, the received light will not be focused back into the laser, but will be directed by the lens toward the region surrounding the laser source, where it is received by the detector structure
Implementation Method 5
one or more semiconductor detector structures are deposited epitaxially in superimposed layers on a substrate, and a semiconductor emitter structure is epitaxially deposited on the top detector structure
Data Source
AI summary
A laser (22) and detector (24) integrated on corresponding epitaxial layers of a single chip (20) cooperate with on-chip and/or external optics (62) to couple light of a first wavelength emitted by the laser to a single external device such as an optical fiber (60) and to simultaneously couple light of a different wavelength received from the external device to the detector to provide bidirectional photonic operation. Multiple lasers and detectors may be integrated on the chip to provide multiple bidirectional channels.