1. A defect detecting apparatus for detecting defects on at least front and rear surfaces of a transparent member, said defect detecting apparatus comprising: an imaging device for focusing and imaging each of said surfaces; a combining device for combining images of said surfaces obtained by said imaging device so as to create a composite image; an eliminating device for eliminating at least one blurred image from said composite image, said blurred image being caused by a defect which resides on one of said surfaces and appears on the other of said surfaces; and a defect detecting device for detecting said defect based on said composite image from which said blurred image is eliminated by said eliminating device.