White light scanning interferometry has gotten a firm position in 3D surface profile measuring field. Recently, the LCD industry gave a chance for this technology to enter into real industry fields. It is known that white-light phase￢shifting algorithm give a best resolution compare to other algorithms, but there are some problems to be resolved. One of them is 300㎚ jump in height profile, called bat-wing effect. The main reason of this problem is an ambiguity of phase￢peak detection algorithm, and some solution has been proposed, but it didn't work perfectly. In this paper, I will show the cases when these effects are occurred, and these height discrepancies will be almost disappeared when broad-band illuminators are used.
