Method of threshold segmentation detection for circular holes in flexible circuit board

Abstract

The invention discloses a method of threshold segmentation detection for circular holes in a flexible circuit board. The method comprises the steps of obtaining a gray scale image of a flexible circuit board according to an original image of the flexible circuit board; segmenting the gray scale image of the flexible circuit board by using an adaptive threshold segmentation method based on a gray scale histogram and obtaining a segmentation result image of the flexible circuit board; obtaining a connected domain contour image of the segmentation result image of the flexible circuit board, performing initial screening based on geometric properties of the connected domain contour, and establishing a candidate set of circles; judging the validity of candidate circles in the candidate set in sequence, determining the valid candidate circles and the invalid candidate circles in the candidate set, and removing the invalid candidate circles in the candidate set; and calculating the circle center, radius and roundness parameters of the valid circles by using a fitting method. The method of the invention can detect the circular holes in the flexible circuit board more quickly and accurately,and realizes the real-time detection of the circular holes; and for flexible substrates, the method of the invention has higher detection precision of the circular holes therein.

Description

technical field [0001] The invention relates to the technical field of image processing, in particular to a threshold segmentation detection method for round holes in a flexible circuit board. Background technique [0002] Flexible circuit board is a highly reliable and excellent flexible printed circuit board made of polyimide or polyester film, referred to as soft board or FPC, with high wiring density and light weight. , The characteristics of thin thickness. With the rapid development of communication, computer, consumer electronics and other industries, FPC, as an important part of electronic products, is also developing rapidly, and the quality of its performance also affects the quality of electronic products to a large extent. Among them, drilling is a key process technology in the production process of flexible circuit boards. It is particularly important to quickly and accurately detect the drilling parameters of flexible circuit boards during the production proce...

AI Technical Summary

Problems solved by technology

The above method is time-consuming and not suitable for real-time detection in the production process of flexible circuit boards, and for flexible substrates with higher wiring density, smaller packaging area and more pins, the detection accuracy of the above method will be higher. Low

Images