Solder Joint Detection via Edge Reference and Contrast Coating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing detection systems for assessing the quality of electronic circuits, particularly AOI devices, face difficulties in detecting soldering points on integrated circuits with sawn housings, as they are not easily identifiable and require precise positioning for accurate detection.
Innovation Solution
A detection system that generates an edge data set from an image data set representing the component, using a pattern detection unit to determine the edge and a coating with titanium dioxide or fluorescent pigments to create a contrast medium for reliable edge detection, allowing for the localization of soldering points even with tolerance in component positioning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional AOI devices are used to detect soldering points, then the detection process is simple, but soldering points on integrated circuits with sawn housings can only be detected with difficulty
Solution Approach 1:
The patent introduces an edge detection mechanism as an intermediary step between the component and soldering point detection. By first detecting the component edge and using it as a reference, the system establishes a coordinate system that enables accurate localization of soldering points even on components with sawn housings, thereby resolving the detection difficulty
Solution Approach 2:
The detection process is segmented into distinct steps: edge detection, coordinate system establishment, and soldering point detection. This segmentation allows each step to be optimized independently, with the edge detection serving as a reliable reference that improves the overall detection reliability of soldering points
2Measurement precision
If lettering on the housing is used to determine component position, then the process is simple, but the position cannot be determined with sufficient precision
Solution Approach 1:
The patent utilizes the contrast between the component housing and its edge (or introduced coating) to create a detectable visual feature. The edge appears as a dark line in the color image, providing a precise and unambiguous reference for position determination that surpasses the precision of lettering-based methods
3Measurement precision
If the component positioning tolerance is large, then the assembly process is flexible, but the soldering points cannot be accurately localized
Solution Approach 1:
The system dynamically adapts to component positioning variations by using the actually detected edge position as the reference, rather than relying on a predetermined or nominal position. This dynamic reference establishment allows accurate soldering point localization regardless of the magnitude of positioning tolerance
Solution Approach 2:
The component itself provides the reference information through its detectable edge, eliminating the need for external positioning fixtures or complex alignment procedures. The edge detection method uses the component's own features to establish the coordinate system, making the system adaptable to positioning tolerances
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 detection of soldering points, including those with partial or insufficient solder wetting, by using electromagnetic radiation and edge-based reference points, improving the assessment of solder joint quality and identifying defective joints effectively.
Implementation Method 1
The detection device has a transmitter for electromagnetic radiation and is designed to generate electromagnetic beams with the transmitter and to send them onto the component
Implementation Method 2
starting from the edge, the component has a coating that reflects the electromagnetic rays on a side facing away from the printed circuit board
Implementation Method 3
the coating is fluorescent. More preferably, the transmitter for the electromagnetic rays is designed to generate fluorescence-generating rays
Implementation Method 4
The detector is arranged and designed to detect electromagnetic rays reflected by the component and to generate an image data set representing the reflected rays
Data Source
Figure 1
Figure 2
AI summary
The invention relates to a detection system (1) for detecting a soldered joint (16, 17) of an electronic component (10), particularly an integrated circuit. The component comprises a cuboid enclosure. The detection system comprises a detection device (2) with an emitter (5) for electromagnetic radiation and a detector (6) for the electromagnetic radiation. The detection device is designed to generate electromagnetic radiation (18, 19) with the emitter and to transmit said radiation to the component. The detector is arranged and designed to detect electromagnetic radiation (18', 19') reflected by the component and to generate an image data set representing the reflected radiation. The detection device is designed to generate from the image data set at least one edge data set representing one edge of the component and to determine in the region of the edge data set, particularly of an image region of the image data set representing the edge, at least one part of the image data set representing a soldered joint and to generate and output a quality signal representing a quality of the soldered joint on the basis of an intensity value, particularly a brightness or grey value of the part of the image data set.