| 摘要 |
PURPOSE:To enable the measurement of the tension of a thin film while running by gauging the angle of a bend generated with a light leverage system using a laser light by applying an external force to the thin film. CONSTITUTION:A laser light 4 irradiated from a laser unit 3 is converted to a parallel scanning light through a scanner 5, a half mirror 6 and a lens 7 and when crossing at the right angle to the thin film 1, it 4 is reflected in the course the same as that when it is incident on the thin film 1 and the light point position is detected 8 through the lens 7 and the mirror 6. In this case, the focused light point is one, but when an angle theta of bend is caused in the thin film 1 by an external force F, the number of light points is two 9a and 9b. The light points 9a and 9b are deviated by a distance D and the tension T of the thin film 1 is measured from the distance D determined by a light leverage type regardless to the position at which the external force F is applied. Thus, the external force F is so minute to cause limited errors in the measurement thereby permitting a highly accurate value to be determined with regard to the tension T even with the resolution in the order of 100mg. |
