Detection of Small Particles on TFT-LCD Using Comparison Method along Scanning Direction of Image Sensor.

Small particles (approximately lager than 1 μm) adhered on to TFT-LCD (Thin Film Transistor-Liquid Crystal Display) plates in a production process cause the defects in circuit patterns. The particles have been detected strictly in a production process by employing automatic inspection systems. In this development, an automatic particle detection system with a high speed and simple configuration has been developed. The high speed inspection has been realized by developing detecting optics whose view field is 4 times as large as conventional optics. The simple configuration has been realized by developing a comparison method along scanning direction of an image sensor. This system is performed so as to detect 1 μm polystyrene latex on a TFT-LCD plate.