Browsing by Author "Fang, Hong-Ren"

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Real-time Image Data Acquisition and Inspection System for Integrated Circuit Wafer after Sawing Process
(2016)
Lin, Chun-Fu
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Fang, Hong-Ren
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Sze, Jyh-Rou
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Lin, Sheng-Fuu
;
Hwang, Chi-Hung
The major defect in integrated circuit wafers after the sawing process is the unexpected cracking from the sawing lane that damages the die area. Traditional defect detection algorithms for integrated circuit wafers after the sawing process can be divided into two parts. The first part is locating the sawing lane area and the second is detecting defects in the sawing lane area. The traditional methods take too long to locate the sawing lane area. To overcome this, this paper proposes a novel method for locating the sawing lane area using low-resolution and gray-value input images. After the sawing lane area is extracted from the original image, defects can be detected by traditional defect detection methods in the sawing lane area or by the method proposed in this paper. Using the proposed defect detection method is faster and better for real-time operation than traditional methods since the proposed method is more concise. Finally, a pioneering image data acquisition and inspection system for integrated circuit wafers after the sawing process is proposed in this paper. Furthermore, the proposed system works in real time because its architecture operates quickly and its proposed algorithm is simple, using low-resolution, gray-value images. Therefore, the proposed system can operate in real time and maintain a high-level detection rate.
Real-time Pitch Diameter Measurement of Internal Thread for Nut using Laser Triangulation
(2017-01-01)
Lin, Chun-Fu
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Hwang, Chi-Hung
;
Fang, Hong-Ren
;
Chen, Chih-Yen
;
Sze, Jyh-Rou
In traditional industrial applications, the thread plug gauge is used to check the pitch diameter of the internal thread of a nut. However, the thread plug gauge can only be used to determine whether the nut was manufactured successfully rather than to measure the value of the pitch diameter. In recent years, several studies have employed a reflected light method such as laser triangulation to scan the outline of an object. However, most research studies using laser triangulation have developed measurement algorithms for specific objects because the properties of an object's appearance and the reflective laser from that object differ greatly. Existing algorithms are consequently not suitable for scanning the outline of the internal thread of a nut and measuring its pitch diameter with laser triangulation. In this paper, we propose a novel, real-time algorithm for measuring the pitch diameter of the internal thread of a nut using laser triangulation. First, a specific image preprocessing procedure designed for a reflective laser in the internal thread of a nut is presented. The result of preprocessing critically affects the measurement accuracy of the proposed method. Thereafter, we propose a measurement algorithm designed for the appearance properties of the internal thread of a nut. Our method can operate in real time because the proposed algorithm can measure the pitch diameter of the internal thread of a nut in only a few steps and simple calculations.