With simple configuration, it forces to the disturbance, the form inclination detection which can measure the tilt angle of skew of the body surface which includes the human body precisely and/or the measurement optical device, optical form inclination detection and/or offer measurement modulo and the circularly polarized light illuminating. Making use of the catoptrics property of the surface of the body surface form and inclination of the observation body detection and/or the form inclination detection which is measured and/or as for the measurement optical device, surrounding around the said body, in every light ray where the regular reflection it does with the illuminating and the said body surface which incidence can point to the light of known completely polarized light state substantially evenly has the polarization image detection device which detects the polarization ellipse of the completely polarized light component of the light ray group which is begun shooting in magnetic declination of specification, reflection is begun shooting, concerning the reflecting interface of the said body which forms the incidence point, from polarization elliptic observation magnetic declination value direction of the entrance placeBeing something which measures the tilt angle of skew for the ejection light ray of the reflecting interface by the step 2 which knows incident angle from the step 1 which informs and polarization elliptic ellipticity theoretical value, manipulating in the same way, optical form inclination detection and/or measurement modulo is formed.簡便な構成で、外乱に強い、人体を含む物体表面の傾斜角を精密に計測できる形状・傾斜検知及び/又は計測光学装置、光学的形状・傾斜検知及び/又は計測法並びに円偏光照明装置を提供すること。物体の表面の反射光学特性を用いて観察物体の表面形状や傾斜を検知及び/又は計測する形状・傾斜検知及び/又は計測光学装置は、該物体の周辺を囲んで実質的に既知の完全偏光状態の光を一様に入射させる照明装置と、該物体表面で正反射し特定の方位角に射出された光線群の完全偏光成分の偏光楕円を検知する偏光画像検出装置を備え、反射射出された光線ごとに、その入射点を成す該物体の反射面について、偏光楕円の観測方位角値から入射面の方位を知るステップ1と、偏光楕円の楕円率理論値から入射角度を知るステップ2によって反射面の射出光線に対する傾斜角を測定するもので、同様に操作して光学的形状・傾斜検知及び/又は計測法が構成される。
