The ridgeline of the ambient shielding tool 34 is crossed with the periphery of the substrate 9, and moreover, a position controlling mechanism for ambiences dislocates the ambient shielding tool 34 in the axial direction. 周囲遮蔽具34の稜線は基板9の周縁に交差するとともに、周囲用位置調節機構が周囲遮蔽具34を軸方向に変位させる。 - 特許庁