SIGN ILLUMINATION SYSTEM AND METHOD

摘要

This relates to a system for and method of illuminating a sign, so that drivers and observers may easily recognize and read the sign and billboard. The apparatus employs an external illumination source that is easy to inspect and maintain. The illumination source and the sign or billboard are separately installed from each other. Light emitted from the illumination source forms an incident angle ( theta ) in the range of 0 DEG to about 30 DEG at any point onthe road sign. A road sign area of the sign is made of a retroreflective sheet having a wide observation angle.