The size of demonstrate board is 400x219x102mm,the five-line illuminant on 85x98x47mm.Putting demonstrate board on the desk and adsorbing five-line illuminent on the board.Then putting five lens in fixed place on the board, openning the illuminant to test by normal eyes,and light will be focused on the retina at this time. Finally, it can be demonstrated the  pathological symptoms of myopic and hyperopia, and we can learn how to correct.