摘要 |
A method for manufacturing a light guide plate, such as a sign or guide display board, that guides light incoming from a side surface of a substrate thereof and guides the light outgoing from a major surface thereof. The method includes arranging fabrication dots in a matrix shape at a rectangular distal surface of a ultrasonic fabrication horn, forming, on a major surface of the light guide plate substrate, reflection dots corresponding to the fabrication dots on the distal surface upon pressing the distal surface of the ultrasonic fabrication horn to the major surface of the light guide plate substrate, and forming the reflection dots in a prescribed range on the major surface of the light guide plate substrate by repeating formation of the reflection dot upon correlative movement of the ultrasonic fabrication horn within the major surface with respect to the light guide plate substrate. |