Fiber Optic Connector Piercing Detection Using Dual Photodetectors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current piercing detection methods in laser material processing are hindered by signal fluctuations due to laser parameter uncertainties, contamination, and high demands on signal processing and transmission, leading to inefficient detection of piercing events in fiber optic cable connectors.
Innovation Solution
A sensor arrangement within a fiber optic cable connector using two photodetectors, where one measures radiation arriving at the output end and the other measures radiation reflected from the workpiece, with a circuit for correlating signals to detect piercing independently of power and pulse frequency, and a fiber bond acting as a near-field aperture for separating useful and process scatter radiation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If photodetectors are positioned below the workpiece to detect passing laser radiation, then piercing detection is enabled without exact knowledge of laser parameters, but signal-to-noise ratio deteriorates due to contamination and scattered light from already cut areas
Solution Approach 1:
The patent moves the photodetector from a position below the workpiece (2D plane) to an integrated position within the fiber optic cable connector (3D spatial repositioning). This dimensional change allows the detector to capture backscattered light at the source rather than from contaminated areas below the workpiece, resolving the contradiction between detection capability and signal quality.
Solution Approach 2:
The fiber optic cable acts as an intermediary between the laser source and the photodetector. By integrating the photodetector within the connector and using the fiber's backscattered light signal, the system mediates the detection process to avoid direct exposure to contaminated areas while maintaining piercing detection capability.
2Measurement precision
If sampling frequency is increased to detect signals with less error according to Nyquist and Shannon theorems, then detection accuracy improves, but signal processing and transmission demands increase significantly
Solution Approach 1:
The patent performs preliminary signal processing by integrating the photodetector and evaluation electronics directly within the fiber optic cable connector. This preliminary action at the source reduces the complexity of subsequent signal transmission and processing by providing a pre-processed piercing signal rather than requiring high-frequency sampling and transmission of raw signals.
3Reliability
If evaluation looks back over a certain period to detect piercing events reliably, then detection reliability improves, but detection speed decreases due to the time required to analyze historical signals
Solution Approach 1:
The patent implements a feedback mechanism where the photodetector continuously monitors backscattered light and provides real-time piercing detection feedback to the control system. This eliminates the need to look back over historical signals, as the integrated detector provides immediate feedback on piercing events, simultaneously improving both reliability and speed.
4Adaptability or versatility
If external sensors are used for piercing detection, then detection capability is achieved, but device complexity and signal transmission demands increase
Solution Approach 1:
The patent merges the piercing detection function with the existing fiber optic cable connector by integrating the photodetector and evaluation electronics within the connector housing. This consolidation eliminates the need for separate external sensors and reduces overall system complexity while maintaining full piercing detection capability.
Solution Approach 2:
The fiber optic cable connector is designed to serve multiple functions: transmitting laser radiation to the workpiece, collecting backscattered light, and providing integrated piercing detection. This multi-functionality eliminates the need for separate external sensing systems, reducing device complexity while maintaining detection versatility.
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
Enables reliable and efficient detection of piercing signals without external sensors, reducing signal transmission demands and maintaining accuracy across varying laser parameters, thus improving processing efficiency and reducing contamination effects.
Implementation Method 1
a first photodetector (6) behind an aperture (9) for measuring radiation (14) which arrives at an output end of an optical cable (12)
Implementation Method 2
a second photodetector (7) in front of the aperture (9) for measuring process scatter radiation (17) reflected from the workpiece
Implementation Method 3
The fiber bond (8) acts as a near-field aperture for separating useful and process scatter radiation
Data Source
AI summary
A sensor arrangement/evaluation which allows piercing detection within a fiber optic cable connector by means of two photodetectors independent of power, pulse frequency and pulse length.