| 摘要 |
PURPOSE:To form easily a bright room projection screen by forming a front lens plate on which a lot of semispherical lenses are arrayed, and a rear lens plate on which a lot of convex lenses whose diameter is small than said lens are arrayed, by using a transparent synthetic resin, and sticking them by an adhesive agent. CONSTITUTION:A plate-like front lens plate 2A on which a lot of small semispherical lenses 4 are arrayed, and a rear lens plate 2B on which a lot of convex lenses 5 whose diameter is smaller than siad lens diameter are formed by a transparent synthetic resin. That is to say, a semispherical surface is arrayed regularly on a substrate, that which forms a metallic layer on its surface is used as a master, a lens plate forming die is made by an electrospark machining, and a lens plate is manufactured by a synthetic resin by using said die. Subsequently, the lens plates 2A, 2B are stuck through an adhesive agent layer 3 by making the lens optical axis coincide and setting the focus to a prescribed position. Therefore, a bright room video projection screen can be manufactured easily. |
