基本信息
摘要：PURPOSE:To enable detection of the thickness or the number of sheets by allowing a polarization surface to be twisted through a thin film made of a synthetic resin, constituents which are transmitted through a second polarization filter to be generated, and the quantity of light to be calculated. CONSTITUTION:When a synthetic resin sheet 4 is inserted between a light- projecting portion 1 and a light-reception portion 2, a polarization direction A of rays is twisted while they are transmitted through this sheet 4, thus generating rays (d) containing a constituent (b) in a polarization direction B. The constituent (b) can be transmitted through a second polarization filter' 21 of the light- reception portion 2 so that it enters a photoelectric conversion element 23 through a focusing lens 22. Then, an amount of twist of the direction of polarization of rays is nearly in proportional to the thickness or the number of the sheet 4 while the rays are transmitted through the sheet 4, thus enabling an output of the element 2:3 to be detected according to the thickness or the number of sheet 4.
摘要附图：
