Progressive lens technology has made tremendous strides over the years．From its first inception in 1907，through the first successful launch in Europe in 1957 and in the United Stated in 1961，progressive lenses have changed and improved with each new development in lens technology．
　From the very beginning，the search was on for the ideal progressive addition lens．one that functioned as smoothly as a single vision lens．Progressive lens provide clearer vision not just for near and far,but also for all distance in between without any abrupt changes or visible lines in the lens．Progressive lenses are divided into four sections：distance，mid-range，nea rand edge．The distance portion of the lens allows you to clearly see anything that is more than a couple feet away,to as far as your eyes can see，The mid—range portion of the lens allows you to clearly see anything that is at an arm's length，such as you computer screen or objects on your desk．The near portion allows you to see up close and read with natural head position．For many lenses wears progressive lenses wears better alternative，offering outstanding clarity and comfort to see at all distance．