In-Situ Real-Time Focus Detection during Laser Processing Using Double-Hole Masks and Advanced Image Sensor Software. - Binh Xuan Cao; Phuong Le Hoang; Sanghoon Ahn; Jeng-o Kim; Heeshin Kang; Jiwhan Noh (Sensors, 2017)

High-Speed Focus Inspection System Using a Position-Sensitive Detector. - Binh Xuan Cao; Phuong Le Hoang; Sanghoon Ahn; Heeshin Kang; Jeng-o Kim; Jiwhan Noh (Sensors, 2017)