| 摘要 |
A back lighting apparatus of a sign board is provided to enable back lighting of low power and high efficiency by using an LED to assure a high luminance surface type light source. A sign board apparatus has an advertisement sheet(31) on an advertisement plate frame(30), and a back lighting device for advertisement content illumination. The back lighting apparatus is a surface type light source, which is formed by continuous arrangement of line type light source blocks. According to the line type light source block having a light guide bar(11) of transparent resin material, a beam output part is formed on one plane along a length direction of the light guide bar. A metal coating film forms a light reflection film by being coated on the other part except the beam output part of the light guide bar. An LED holder has an LED power supply terminal. One or more than two LEDs are installed in the LED holder and radiates a beam into the light guide bar.
|
