| 摘要 |
PURPOSE:To make it possible to confirm th operation of a LED easily and definitely by directly detecting the output of an infrared-ray LED emitting light by a photo detector and by displaying out its operation state. CONSTITUTION:As shown by dotted lines, LED3 radiates infrared rays at a wide angle and those radiated out are sent to a distant point after being made parallel through lens 2. In the optical system, on the other hand, photo detector 5 is arranged where the main energy beam of an infrared-ray LED arranged close by the focus can not be prevented near the LED. Consequently, the output of LED is directly detected by detector 5 and the operation state of the LED is displayed out, so that the operation of the LED can be confirmed easily and definitely. |
