Laser Light Source Device Temperature Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing laser light source devices face challenges in accurately controlling the temperature of semiconductor laser elements due to time lags caused by heat conduction through mediums like heat sinks, leading to fluctuations in the semiconductor laser element temperature.
Innovation Solution
A laser light source device configuration that includes a semiconductor laser element, a cooler, an element temperature measurement section, a cooler temperature measurement section, and a controller that adjusts the cooler temperature based on the semiconductor laser element's temperature, ensuring precise control by measuring and controlling the cooler temperature rather than the element temperature directly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If element temperature is measured and controlled directly, then temperature control accuracy should be high, but time lag occurs due to heat conduction through medium causing temperature fluctuation
Solution Approach 1:
The patent introduces an intermediary approach by measuring the cooler temperature (which is closer to the semiconductor laser element) instead of directly measuring the element temperature. This intermediary measurement point reduces the time lag caused by heat conduction through the medium while still providing useful temperature information for control purposes.
Solution Approach 2:
The system performs preliminary cooling action by controlling the cooler temperature before the semiconductor laser element temperature actually changes. By anticipating the temperature change and acting in advance through the cooler, the system reduces the time lag and stabilizes the element temperature more effectively.
2Loss of time
If cooler temperature is measured and controlled, then time lag is reduced, but element temperature stabilizes at higher or lower than desired temperature
Solution Approach 1:
The patent implements a feedback mechanism where the measured element temperature is continuously compared with the desired target temperature. Based on the temperature difference, the controller adjusts the cooler temperature dynamically to compensate for the stabilization error, ensuring the element temperature converges to the desired value.
Solution Approach 2:
The system dynamically adjusts the cooler temperature setting based on the measured element temperature. Rather than maintaining a fixed cooler temperature, the controller continuously modifies the cooler temperature to account for changes in heat generation, ambient conditions, and thermal resistance, thereby maintaining accurate element temperature stabilization.
3Loss of energy
If medium such as heat sink exists between element and cooler, then heat conduction occurs, but temperature control accuracy decreases due to time lag
Solution Approach 1:
The patent uses the cooler temperature as an intermediary measurement that correlates with the element temperature without requiring direct measurement through the heat conduction medium. This approach bypasses the accuracy degradation caused by the medium's thermal resistance and time lag.
Solution Approach 2:
The patent replaces direct mechanical/thermal measurement at the element with an electrical control system that measures cooler temperature and uses feedback control algorithms to achieve accurate element temperature control, substituting direct thermal coupling with intelligent control.
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 allows for highly accurate stabilization of the semiconductor laser element's temperature within a desired range, reducing fluctuations and preventing extreme temperatures that could lead to issues like rust, short circuits, or reduced device lifespan.
Implementation Method 1
since a medium such as a heat sink exists between the semiconductor laser element and the cooler, it takes time to conduct the heat generated from the semiconductor laser element, to the cooler
Implementation Method 2
an element temperature measurement section that measures an element temperature which is a temperature of the semiconductor laser element; a cooler temperature measurement section that measures a cooler temperature which is a temperature of the cooler
Data Source
AI summary
A laser light source device has a light source unit including a semiconductor laser element that emits laser light having a predetermined wavelength band at a temperature from an allowable lower limit temperature to an allowable upper limit temperature, a cooler, an element temperature measurement section, a cooler temperature measurement section, and a controller that controls the cooler. The controller controls the cooler such that the cooler temperature approaches a set temperature. The controller lowers the set temperature as long as the element temperature exceeds the allowable upper limit temperature, and the controller increases the set temperature as long as the element temperature falls below the allowable lower limit temperature.