| 摘要 |
<p>A light projecting method suitable for observing the state of the surface of an object to be measured, a surface inspection method using this light projecting method, and an apparatus used to implement these methods. In a light projecting apparatus which projects light from a light source through a projection lens unit, the projection lens unit has a characteristic of vertical aberration caused by spherical aberration on the light source side of the projection lens unit such that the deviation from the paraxial image plane to the image forming point increases or decreases with the incidence height. The light source is outside a group of image forming points.</p> |
