| 摘要 |
PURPOSE:To obtain a read-only storage device in which storing density is improved and the size of a storing medium is reduced, by laminating plural pairs of layers on a base plate each pair of which consists of an optically transparent layer and a partially opaque layer. CONSTITUTION:Plural pairs of optically transparent layers 13, 11, 9, 7, and 5 and partially opaque layers 12, 10, 8, and 6 are laminated on a base plate 14. For example, a light source 2 and a detector 1 both of which move at an equal speed relatively to the base plate 14 are arranged so that incident light 4 from the light source 2 is penetrated into screens 15-22 which are stored data in the partially opaque layers and the reflected light is penetrated into the detector 1. By adjusting the focus of the detector 1 to one of the partially opaque layers, data in the required layer is taken out. |
