| 摘要 |
PURPOSE:To enable the addition of photosensors without causing a higher cost, by separating a sensor portion into several photosensors and a common measuring section to selectively control an optical switch connected to an optical transmission path and an optical sensor. CONSTITUTION:A central transmission controller 1 sends control information to select one of photosensors 5a-5c. Synchronizing control information among terminal transmission controlling sections 2a-2c, the section 2a closes an optical switch 4a connected to the photosensor 5a as specified. Therefore, optical information of the sensor 5a reaches a measuring section 3 through the switch 4a and an optical fiber transmission path 7 and undergoes a signal processing to be sent to a terminal. In this manner, the measuring section 3 is made common to the several sensors 5a-5c and one sensor is connected to one measuring section for reading. This enables addition of sensors without causing an increase in the cost, the increase due to the addition of the measuring sections and terminals. |
