LIGHT GUIDE PLATE, DISPLAY UNIT INCLUDING THE LIGHT GUIDE PLATE, TRAFFIC SIGN INCLUDING THE DISPLAY UNIT, AND METHOD OF MANUFACTURING THE LIGHT GUIDE PLATE AND METHOD OF MANUFACTURING THE TRAFFIC SIGN

摘要

EVEN THOUGH NO LIGHT SOURCE IS PROVIDED IN THE VICINITY OF EACH CURVED APEX OF A MAIN FACE, THE BRIGHTNESS DIFFERENCE DEPENDING ON THE LOCATION ON THE MAIN FACE IS REDUCED, AND A LIGHT GUIDE PLATE THAT CONTRIBUTES TO ELECTRIC POWER SAVING CAN BE PROVIDED. IN ADDITION, WITH THIS LIGHT GUIDE PLATE, A DISPLAY AND A TRAFFIC SIGN INCLUDING THE DISPLAY THAT CAN KEEP A SMALL BRIGHTNESS DIFFERENCE DEPENDING ON THE LOCATION ON THE MAIN FACE, AND REDUCE THE POWER CONSUMPTION. MEANS TO SOLVE THE PROBLEM, THE RATIO OF THE AREA OF THE FIRST DIFFUSION DOTS 32A AND SECOND DIFFUSION DOTS 32B WITHIN THE SECOND DIFFUSION REGION IS GREATER THAN THE RATIO OF THE AREA OF THE FIRST DIFFUSION DOTS 32A WITHIN THE FIRST DIFFUSION REGION. THUS, EVEN THOUGH NO LIGHT SOURCE UNIT IS PROVIDED AT A CURVED SECTION 30A, THE BRIGHTNESS DIFFERENCE (THE UNEVENNESS OF BRIGHTNESS) DEPENDING ON THE LOCATION ON THE ENTIRE MAIN FACE IS REDUCED, AND ELECTRIC POWER SAVING CAN BE ACHIEVED. FIGURE 1