| 摘要 |
<p>PURPOSE:To quickly carry out accurate dimming into an objective lightness, provide a wide range for dimming performance, and reduce the fear of failure. CONSTITUTION:An illumination device 3 for visual sensor uses a straight form fluorescent lamp 28 as a light source and illuminates the view field of a visual sensor 2, wherein the bulb 31 of fluorescent lamp 28 has a light projecting region restricted to partial angular zone and the light distribution curve has such characteristics as uneven about the center of light emission 32 of the lamp. The lamp is mounted rotatably round its axis. A motor 42 is furnished to rotate this fluorescent lamp 28, and the lightness for illuminating the view field is increased and decreased by turning the lamp 28 round its own axis with this motor 42.</p> |
