High density printing paper quality investigation

Light has been used to examine the quality of the products or surface finishing of most products by the industries in recent times. In this research, a lab module tester was designed and built to investigation on the different type of printing paper quality which available commercially was done. Laser light was utilized as a manipulator to distinguish the quality of printing paper and the light reflectance element was used. The photodiode was used as sensing element to detect the reflected light from the surface of printing paper. The both of laser diode and photodiode were placed in a light box. The laser was used to emit light on the sample and the photodiode detects light intensity from the surface printing paper in the light box. Different level of intensity correlates to different voltage output. The investigation on the different type of printing paper including of 70 g/m², 80 g/m² and 100 g/m² were done respectively. The result showed that the 100 g/m² printing paper has a higher reflected voltage output compared to 80 g/m² and 70 g/m² printing paper.