| 摘要 |
<p>An apparatus includes light projecting means 1-3 for projecting light beams to an observation target portion of an object through a predetermined path, recursive reflecting means 4-7 for reflecting, in an incident direction, the incoming light beams reflected by the observation target portion, and light receiving means 8 and 9 for receiving the light beams reflected by the recursive reflecting means and the observation target portion and coming through the predetermined light path. This can improve maintenance properties, reduce cost and improve accuracy in inspection. <IMAGE></p> |
