A method of scanning an information recording medium and a scanning apparatus for an information recording medium that uses the method scan for defects in respective resin layers of an information recording medium that has a plurality of resin layers and a plurality of information layers, which are separated by the respective resin layers, laminated on at least one surface of a substrate. A gate electrode is subsequently defined after which a pair of sourcedrain zones, each having a main portion and a more lightly doped lateral extension, are formed in the semiconductor body. An edge direction is selected based upon the estimating the edge direction proximate the first pixel of the input image using a second technique. As a result, according to the method and apparatus of the present invention, the gate current Ig through the first capacitor is equal to the current drained off through second compensation transistor. Thermal oxide films are formed having an approximately constant film thickness ranging from the bottoms to the edges of the openings of trenches so as not to give stress to N type epitaxial layers.