| 摘要 |
PROBLEM TO BE SOLVED: To provide a light guide plate for an illumination apparatus designed for a plant factory using artificial light, and to provide a method of manufacturing the light guide plate.SOLUTION: A dot pattern on a top surface 14a of a light guide plate 14 is imprinted such that a plurality of circular dots 40 are arranged at an equal interval "a" and a diameter of the circular dot becomes larger toward the central part and four corners of the top surface 14a of the light guide plate 14. Since a place having a larger diameter of the dot 40 has an increased area where refraction effect of optical path by the dot 40 is obtained, per unit area of the top surface 14a, refraction effect of the optical path also becomes larger in a place closer to the central part and four corners of the top surface 14a of the light guide plate 14. The light guide plate 14 has a predetermined dot pattern by imprinting circular recessed dots on one of front and rear surfaces of a rectangular acrylic board in a plan view by a laser beam machine 48. |
