螢光灯による人工照明―各種色彩の移動視標が眼近点距離に及ぼす影響―

Fluorescent lamp was compared with incadescent lamp concerning the influence upon the shift of the near point after the task seeing the rotating objects with colored stripes. The apparatus is shown in Fig. 1. The drum is covered by paper with stripes of white and one of the standard colors is used by Japanese Color Institution (black, red, yellow and green). Each stripe has the width of 3 cm and an angle of 45° to its moving direction. It rotates at the speed of 60 times per minute. Each examinee has to see this object through a window of 4×5cm opened in the midst of black carton paper, from the distance of 30cm for 20minutes. During the examination he is requested to number the stripes in order to fix his attention to this visual activity. Examinees were men and women of 19-33 years old, with normal vision and without any ophthalmological defect. Mazda Daylight Fluorescent Lamp (FI-200, 20 watt) and Mazda Gas-filled Lamp (100 volt, 100 watt) were used for the examination. The near point optometer by Dr. Ishihara was used for the measurement of near point. The results were as follows: 1) In the illumination of 200 lux, the near point shifts much further in fluorescent lighting than in incadescent lighting. This is true in every color. 2) In fluorescent lighting black and red are more effective than yellow and green. In incadescent lighting no distinguishable difference can be seen among the colors. 3) The examinee feels more comfortable by the case of incadescent lighting than fluorescent lighting. Yellow is the best and green follows in his subjective feeling. From the above results, the authors conclude that incadescent lighting is better than fluorescent lighting when we are engaged in works to see moving objects.