Bekk Smoothness Tester (HK Model) - OpTest

Smoothness of paper is one of the important factors to evaluate writing and printing aptitudes of paper. With this machine, test is conducted in the following procedure: place a sheet of paper on the well-polished surface of glass constituting an optical surface, apply a 0.1 MPa pressure on the top of the paper and measure the time needed for a 10cc air to penetrate through the gap between the paper surface and the glass surface. To solve the problem of consumption of much time for measurement of specimens with a high smoothness, a rapid measurement system is provided, which can measure penetration time of 1cc air, 1/10 of the standard air volume.