Tunable Laser Calibration Without Active Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for calibrating and tuning tunable semiconductor lasers require active temperature stabilization and cooling, leading to increased costs due to the need for hermetic packaging and external laboratory equipment, including wavelength lockers and temperature-stabilized filters.
Innovation Solution
A method for calibrating a tunable semiconductor laser without active temperature stabilization, involving the selection of phase and reflector currents to achieve desired frequency bands, scanning for stable operating points, and storing tuning lines for continuous frequency adjustment, using existing network components and conventional detectors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If active temperature stabilization and cooling is used for laser calibration, then stable and powerful light emission is achieved, but cost increases due to hermetic packaging and cooling equipment
Solution Approach 1:
The patent changes the operating parameters by applying different currents to the phase section and Bragg reflector section of the laser. By scanning these currents and identifying stable operating points, the method achieves reliable laser emission without requiring active temperature stabilization or cooling systems, thereby reducing device complexity and cost.
2Measurement precision
If external laboratory equipment and wavelength lockers are used for calibration, then frequency accuracy is improved, but device complexity and cost increase
Solution Approach 1:
The patent enables the laser to perform its own calibration by scanning currents through the phase and Bragg reflector sections and detecting stable operating points internally. This self-service approach eliminates the need for external laboratory equipment and wavelength lockers, reducing device complexity while maintaining frequency accuracy through the inherent stability of the identified operating points.
Solution Approach 2:
The method uses feedback from detecting laser emission characteristics at different current combinations to identify stable operating points. By monitoring the laser's own output and adjusting currents accordingly, the system achieves accurate frequency calibration without external equipment, resolving the contradiction between measurement precision and device complexity.
3Stability of the object's composition
If the laser is cooled using a thermo-electric cooler, then stable operation is maintained, but manufacturing cost increases
Solution Approach 1:
The patent achieves operational stability by changing electrical parameters (currents to phase and Bragg reflector sections) rather than relying on thermal cooling. This approach eliminates the need for expensive thermo-electric coolers and hermetic packaging, reducing manufacturing cost while maintaining stable laser operation through electronically controlled current scanning and operating point identification.
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 reduces costs by eliminating the need for cooling and hermetic packaging, allowing for efficient calibration and tuning of semiconductor lasers within existing optical communication networks without external laboratory equipment, while maintaining stable and high-power lasing.
Implementation Method 1
a tunable laser of the type DBR, MGY-DBR, SG-DBR, SSG-DBR, DS-DBR or the like, comprising at least a phase section and at least one or two Bragg reflector sections to which different currents are applied
Implementation Method 2
at least one or two Bragg reflector sections to which different currents are applied
Data Source
AI summary
Method for calibrating a tunable semiconductor laser having a phase section and a first Bragg reflector section, through which sections a phase current and a first reflector current, respectively, is applied, includes: a) selecting a phase current; b) identifying a range of reflector currents that achieves emission of light from the laser within a desired frequency band; c) scanning the reflector current(s) over the range of reflector currents, for each of at least two different phase currents, and reading the relative output power of the laser for each point scanned; d) identifying one stable operating point; e) identifying and storing one stable, continuous tuning line as constructed by interpolating; f) calibrating the laser frequency and observing a fed back signal from a target for the light emitted from the laser; g) measuring the temperature of the laser; and h) storing temperature and one operating point along the tuning line.