摘要 |
<p>An illumination apparatus in which angles and positional deviations of a laser beam on an illuminated surface can be detected by one detecting system with high accuracy. The illumination apparatus includes a light dividing unit (such as a beamsplitter) that is located between a laser source and the illuminated surface and that splits off a portion of the laser beam, a detecting unit that detects positional deviations and angular deviations of the laser beam relative to a reference axis based on the split off portion of the laser beam, and a light controlling unit, such as a shutting member with a pinhole. The light controlling unit is positioned on the optical path between the laser source and the illuminated surface when an angle of the laser beam are detected relative to the reference axis. The shutting member is removed from the optical path when positional deviations of the laser beam are detected relative to the reference axis. <IMAGE></p> |