| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a luminescence source which eliminates a problem of burning-out of a bulb and a need for maintenance (maintenance-free), and reduces the power consumption by replacing only the existing luminescence source while using an existing case of a sign. <P>SOLUTION: A circular light guide plate 10 has a central window part 12 which is formed by hollowing out a center part of the light guide plate in a manner of making a circle with a radius of about one third of that of the light guide plate. The light guide plate also has a plurality of rectangular housing window parts 14 for housing the source of luminescence. The rectangular housing window parts 14 are formed by hollowing out the outer side of the central window part 12 of the light guide plate in a direction being in contact with a concentric circle. The alternative LED luminescence source for an internally illuminating sign comprises the circular light guide plate 10, a first LED array 16a arranged toward the center side of the light guide plate and a second LED array 16b arranged toward the outer side of the light guide plate, of which the first and second LED arrays 16a, 16b are housed and held in each of the housing window parts. The circular light guide plate has a reflection sheet on its reverse face. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
