Laser Machining Device Contamination Correction via Reflected Light
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Laser machining devices face challenges due to contamination of external optical systems, leading to focus position shifts and reduced laser power, resulting in machining defects and the need for frequent maintenance, especially in automatic operations, where existing solutions complicate the device and are not compatible with all optical systems.
Innovation Solution
A laser machining device that corrects processing conditions prior to machining by using a reflection plate or half mirror to measure returning light energy, allowing for focus and laser power adjustments based on contamination levels, without requiring additional sensors, thus enabling retrofittable solutions for existing devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If temperature sensors or scattered light sensors are attached to the external optical system to detect contamination, then contamination detection capability is improved, but device complexity increases and the external optical system becomes heavier
Solution Approach 1:
A reflection plate is introduced as an intermediary object to enable indirect measurement of optical system contamination. The plate reflects laser light back through the optical system, and changes in the reflected light energy detected by an existing sensor indicate contamination levels, eliminating the need for additional sensors on the optical components themselves
Solution Approach 2:
The patent replaces direct physical sensing mechanisms (temperature sensors, scattered light sensors) with an optical measurement approach using existing laser light and reflection principles. This substitution leverages the laser system's own light source and existing detectors to infer contamination without adding mechanical sensing components
2Measurement precision
If additional sensors are attached to detect contamination, then measurement capability is improved, but the external optical system becomes heavy affecting mechanical performance
Solution Approach 1:
The reflection plate serves as a mediator that enables measurement without direct attachment to the optical system. By placing the plate in the optical path and measuring reflected light, contamination information is obtained without adding weight to the optical components
Solution Approach 2:
The system uses the reflection plate to create an optical copy or representation of the light path conditions. By measuring the reflected light properties, the system infers contamination state without physically sensing the optical components themselves
3Ease of repair
If maintenance is performed after machining defects occur, then response to actual problems is improved, but productivity decreases due to large number of defective parts
Solution Approach 1:
The system performs preliminary detection of contamination before it causes machining defects. By continuously monitoring reflected light energy from the plate, the system identifies contamination early and triggers maintenance before quality degradation occurs, preventing defective parts production
Solution Approach 2:
The system establishes a feedback loop where reflected light energy measurements continuously monitor optical system health. When contamination reaches threshold levels, the system provides feedback to stop operation and initiate maintenance, enabling proactive rather than reactive maintenance scheduling
4Device complexity
If the focus position is not corrected due to contamination, then device simplicity is maintained, but manufacturing precision deteriorates due to focus position shifts
Solution Approach 1:
The system performs preliminary detection of focus position shifts caused by contamination before machining begins. By measuring reflected light energy and comparing it to reference values, the system identifies focus deviations early and corrects them, ensuring precision without adding complex real-time correction mechanisms
Solution Approach 2:
The system uses a simplified measurement approach that detects focus shifts and contamination through reflected light energy changes. Rather than implementing complex active correction systems, it performs partial correction by identifying when correction is needed based on energy measurements, maintaining simplicity while improving precision
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 prevents machining defects by aligning focus positions and adjusting laser power before machining, prolonging maintenance intervals and ensuring continuous automatic operation without the need for additional equipment, making it compatible with various optical systems.
Implementation Method 1
a reflection plate disposed perpendicularly to an optical axis of laser light and having a constant reflectance with respect to the laser light; a returning light measurement unit configured to measure an energy amount of returning light reflected by the reflection plate
Implementation Method 2
an external optical system configured to guide laser light from the laser oscillator and focus the laser light on the surface of a workpiece
Implementation Method 3
a laser oscillator; an external optical system configured to guide laser light from the laser oscillator
Data Source
AI summary
A laser machining device includes a storage unit configured to store a reference value based on an energy amount of returning light when laser light is emitted, in a state where external optical system is not contaminated, toward a reflection plate with a predetermined output low enough not to melt or deform the reflection plate such that a focus position of the laser light aligns with a predetermined position, and a processing condition correction unit configured to correct, prior to laser machining, a processing condition in accordance with the contamination level of the external optical system, wherein the processing condition correction unit includes a laser power correction section configured to correct a laser power of the processing condition based on the measurement value measured by a returning light measurement unit and the reference value.