Polarization plane control device 106 according to an embodiment of the present invention is a liquid crystal element and the polarizing plate, it can be converted to linearly polarized light of the polarization plane of an arbitrary non-polarized light by the voltage. Get an image by sending an imaging start signal to the image sensor 110 and simultaneously irradiate the subject rotate the polarization plane of light sends a command of the polarization plane rotation in the polarization plane control device 106, synchronizer 112, a plurality of times this to. The video image signals are sent to the image processor 108 via the video signal line 111. Therefore, to process the variation in the luminance value due to changes in the illumination plane of polarized light to determine the candidates for the azimuth angle of the surface normal from the brightness maximum angle image, determine the zenith angle of the surface normal from the intensity modulation depth image, the azimuth normal image of the surface groove is produced by resolving ambiguity.本発明の実施形態における偏光面制御素子106は、偏光板と液晶素子から構成されており、電圧により非偏光を任意の偏光面の直線偏光と変換できる。同期装置112は、偏光面制御素子106に偏光面回転の指示を送り照明の偏光面を回転させ被写体に照射すると同時に撮像素子110に撮影開始信号を送って映像を取得し、これを複数回実施する。撮像映像の信号は映像信号線111を経由して画像処理プロセッサ108に送られる。そこで照明偏光面の変化にともなう前記輝度値の変動を処理し、輝度最大角画像から表面法線の方位角の候補を求め、輝度変調度画像から表面法線の天頂角を求め、方位角の不定性を解決して表面グルーブの法線画像が生成される。
