دراسة وضوح الكتابة بالالوان المختلفة على لوحة بيضاء في حالة الاضاءة الضعيفة

Abstract

The good lightness inside class room is important for resolution of written lesson on the board it's one of the condition to connect the lesson and to protect the student safety, we write three texts (black, green, blue) on a board inside class room without use florescent, we only indirect sun light that come from window. The text on different distances from the board mean contrast picturing using digital camera has been study as a function of distance between board and digital camera. The image edge estimated using soble operator for three texts to introduce which color that give best resolution in the case absent lighting inside class room. It is found that using black color in writing given god result in resolution of written text picture on the board.