Multi-Lane Optical Module De-Focusing for Eye Safety
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional optical transmitter modules face challenges in maintaining high-frequency performance and eye safety due to excessive optical power, and de-focusing techniques are inadequate for multiple signal lanes as they affect coupling efficiency unevenly across different optical beams.
Innovation Solution
A three-lens optical module system where the first lens converts divergent beams into collimated beams, and the second lens, after precise alignment and adjustment, controls optical power output within a preset range by shifting along the optical axis to ensure efficient coupling with the third lens and coupling fiber, thereby maintaining optimal power levels across all signal lanes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the bias current is adjusted or decreased to reduce the optical output power, then the eye safety is improved, but the high frequency performance degrades due to lowered resonant frequency
Solution Approach 1:
The patent introduces a de-focusing mechanism as an intermediary element between the laser diode and the optical fiber. By shifting the focal point of the LD from the end of the optical fiber, this intermediary mechanism reduces optical output power while maintaining the bias current at levels that preserve high frequency performance and resonant frequency characteristics.
2Object-affected harmful factors
If the de-focusing is applied to one optical beam, then the optical power for that beam is reduced, but the coupling efficiency for other optical beams becomes inadequate
Solution Approach 1:
The patent applies segmentation by providing a separate de-focusing mechanism for each optical beam or signal lane. Instead of using a single de-focusing approach for all beams, the invention segments the optical paths and implements individualized de-focusing adjustments for each lane, ensuring that each beam achieves optimal coupling efficiency while maintaining reduced optical power levels.
Solution Approach 2:
The patent implements local quality by allowing each optical beam to have its own optimized de-focusing distance and focal point position. Rather than applying a uniform de-focusing setting across all beams, the invention enables each lane to have tailored optical characteristics matched to its specific coupling requirements, thereby maintaining high coupling efficiency for each individual beam.
3Power
If the end of the optical fiber is shifted from the focal point of the LD, then the output power is reduced, but the coupling condition becomes inconsistent across different optical beams
Solution Approach 1:
The patent applies dynamics by making the focal point position adjustable and adaptable for each optical beam rather than fixed. The de-focusing mechanism allows dynamic optimization of the focal point distance for each lane based on its specific requirements, enabling the system to maintain consistent coupling conditions across all beams while achieving reduced output power levels.
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 maintains high-frequency performance while ensuring eye safety by evenly adjusting optical coupling efficiency across multiple signal lanes, preventing overpowered conditions and enhancing coupling tolerance and reducing backward reflections.
Implementation Method 1
a first lens coupled to the LD... placing the first lens in a first position at which the first lens converts an optical beam output from the LD into a collimated beam
Implementation Method 2
a second lens coupled to the first lens... placing the second lens in a second position at which the second lens converts the optical beam output from the first lens and passing through the second lens into a collimated beam
Implementation Method 3
a third lens coupled to the second lens and a coupling fiber coupled to the third lens
Data Source
AI summary
A method to produce an optical module, which includes more than one signal lanes each providing a semiconductor laser diode (LD), a first lens, and a second lens, is disclosed. The method first places the first lens in a position at which the optical beam output from the LD becomes a collimated beam, then, slightly shifts so as to be apart from the LD to convert the optical beam into a concentrated beam. The second lens is first placed in a position at which the optical beam from the first lens becomes a collimated beam, then, shifted so as to be apart from the first lens such that the optical output get through the coupling fiber becomes within a preset range.